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lh2.4 warm start issue (fine cold or hot) 200

volvo 240 lh2.4 all stock except does not have a 25amp fuse, PO has installed blade fuse box.

will start and run w/out any issues when cold.
after driving it for 30 minutes or so and then letting it sit for another 15-30 minutes it will start but then stalls out with rough idle unless given a little gas.
Give it a little gas and its fine.

if i stop for like 5 minutes or so it starts fine w/out giving it gas.
if it sits longer for like a few hours it cranks fine.

Verified TB is clean
both fuel pumps work and sound fine using the tube to ear test
fuel relay is new/replaced with a few of them i have around
flametrap all new
battery and grounds appear good


What do I check?
I was thinking of cleaning IAC
maybe check injectors somehow?
unplug cold start injector?
swap MAF from one of my other lh2.4?

Any other ideas?








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Thanks for the feedback.
Update: only partial tests completed due to lack of time/daylight.

Car is my sons at college so I don't have full access so testing is whenever I can.

The symptom has now changed to being slow to crank (like a battery that doesn't have juice but just makes it over, like it cranks over a few times before it starts) but then starts fine and runs fine, doesn't require gas or stumble now on warm start. maybe this is a clue to what may be failing/about to fail?

Its nice to have another 240 with same parts to troubleshoot and prevent throwing parts at it.

Checked all plugs and they look good, all normal coloration.
Verified all plug and coil wires are seated.
Verified cap and rotor are free from corrosion.
Swapped coil from my other car.
battery cables look good and grounds look good.
FPR was dry and no signs of fuel in vac line.
Car has 14.2 charge when running, so I assume the ALT is good.
Verified CPS cables are not frayed or smashed or melted, did not remove it though.

Will try the following on sunday when car returns:
swap battery from other 240
swap ICM from other 240 that has bosch, the current one looks aftermarket.
maybe swap all plug wires and dist/rotor just to be sure?
don't really want to swap CPS but may.
I guess I will focus on electrical/ignition items until I exhaust them before looking to fuel delivery. Any other ideas or tips are welcome..






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an iffy crank sensor will cause a slow cranks like the battery is low or the ignition timing is off. have to scope it to catch it for that. usually they just die when hot, then cool off and act ok.



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Well, it had a no start this evening, doesnt even try to crank.
Swapped battery and it made no difference.
Acts like a bad starter like it will 1 out of 10 times make a click but not try to turn over. engine was hot and so was the starter.

My son will try again in the AM and bring it home so we can swap CPS if it starts, otherwise we will tow it.

I will digest all of your suggestion.

Thanks!



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Hi,

I have been buying this item since 2019 for my three nineties cars and have used them all up to this year.
I ordered two more, for stock and got them yesterday.

https://www.amazon.com/AIP-Electronics-Crankshaft-Compatible-Replacement/dp/B00FSCAQEA/ref=pd_ybh_a_d_sccl_13/145-1092663-4274058?pd_rd_w=yLzYS&content-id=amzn1.sym.67f8cf21-ade4-4299-b433-69e404eeecf1&pf_rd_p=67f8cf21-ade4-4299-b433-69e404eeecf1&pf_rd_r=8KNRWR88JKJ9DAAFER15&pd_rd_wg=66Fr7&pd_rd_r=86026dc2-6eed-4e7b-b4b3-2a5ae0553301&pd_rd_i=B00FSCAQEA&psc=1

So, if you are in the market? Here is a guide that has definitely worked for me.

Phil



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Update:
towed car home, cleaned every ground(wipe off and sand surfaces clean) i could find from battery and all the connections to the starter.
When trying to crank I hear a light whirring sound, but no clicking that i assume is starter?
The key has the click feeling when going from 1-2-3 that it should.
When trying to crank i see no voltage drop on battery, it stays at 12.5 as if nothing is being pulled from battery by the solenoid/starter.
When trying to crank all dash lights come on/off as expected, the headlights will turn off/flash when trying to crank.
Tried starting in neutral and wiggling shifter(AT) but did not inspect N safety switch(will check tomorrow)

I guess I have ruled out CPS or ICM because I disconnected each of them on my perfect working 90 240 and the car would try to crank but not start. totally different than the non starting 91. I am thinking that CPS/ICM don't come into the equation until after the starter has done something?

I think the plan is to just pull starter out and replace w/ another one. A bosch one. The current one that is suspect looks to be aftermarket for sure.
I am concerned about the car since the evolution of starting problems changed in 2 weeks as follows:
1) warm easy crank/start but a quick stall unless given gas (but perfect cold start w/ no stall).
2) To then a slow crank at anytime(cold/warm) but would start and not stall to
3) a complete no crank all

I feel like I am missing something even if i replace starter and it starts, like something may have caused the starter failure during those 2 weeks of evolving symptoms. if the theoretical underlying issue is not found would continue to cause problems. or I have 2 problems and the slow crank was somehow masking the stall issue and if i get car to start then that issue will return.

I am assuming no EFI issues would result in a car not trying to crank.



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Hi,

Yes you are correct. “no EFI issues would result in a car not trying to crank.“
Unless the engine turns nothing happens with the running system.

What worries me more is you think you have an aftermarket starter.
That is a tell all in itself.
There would have to have been a whole lot of cranking in order to wear out the original Bosch starter.

Since you think the aftermarket one bit the dust, one has to ask why has there been so much cranking.
It appears that one fault has lead to another. Like intertwined.
An engine out of tune is just the beginning of whether an CPS is involved or not. Cranking excessively take s a toll that rings bells, even if the bell is only thumped lightly in the beginning. 🤔🥴😵‍💫

TLC is definitely needed. That’s “Take a Look Carefully.” 🤭
These engines and their outer components are time tested to go miles counted by an extraordinary wide number column on the odometer for their time.
When compared to the others of USA’s domestic vehicles there was pride in Volvo’s glinting.
Even though the gears inside the odometers were junk! But that was another countries problem.

Good luck with the progress.
Phil




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Have only had car for 3 weeks and have just been going over things and was planning on and chipping away at basic stage 0 but have been side tracked with this issue.
Looking through all the receipts that came with car it appears an aftermarket (ultra 12211 ?) starter was purchased in 2014. so i guess thats 10 years of cranking on it.



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Hi ?,

It looks like more than one issue going on to me.
I didn't see that you checked for OBD codes.

You can sort out the No Crank problem by using the service port connector in
the engine bay to see if that cranks the engine normally.
Put +12V from the Battery to that port with a jumper wire.
If it then cranks OK you can suspect the ignition or interlock switch.
Both switches need to carry enough current to pull in the starter solenoid.

Alternatively just short the starter solenoid with a big screwdriver and see if
it cranks OK. Then go back to find the wiring culprit.

Do this before swapping the starter.

Confirm that you pulled apart and cleaned all of the piggybacked wires at the battery positive terminal, then used Penetrox or conductive grease.

Get it cranking normally and then go back to the other problem.

You're lucky to have a donor parts car there. Swapping fuel relays might not solve the problem if there's loose or corroded relay socket pins.
Make a gauge with a hunk of copper wire and a 1/4" male spade lug to verify
connector pins are tight. Use Penetrox on the pins.

Check your CPS, AMM, & power stage connector carefully for damaged pins, Use Penetrox. Your power stage is ready for re-seating with fresh thermal compound.

You might want to swap ECU's, Be sure to disconnect the battery
for several minutes before pulling the ECU connector!

Study Ron Kwas's website with his fine write-ups explaining how poor connections can rain on your parade: Note the article about the lowly 1/4" spade terminal. That's what's used for the fuel relay.
Find the article about ACZP at Ron's site:
http://www.sw-em.com/techarticles.htm

Just some of the outstanding articles at Ron's site.

http://www.sw-em.com/Wiring%20Notes.htm#the_lowly_250_push_on_terminal

http://www.sw-em.com/Deoxit_D5_Additional.htm#my_recommendations

http://www.sw-em.com/voltage_drop_in_headlights_power_in_hex_connector.htm

http://www.sw-em.com/Realworld%20Experiences%20with%20Electrical%20Corrosion%20and%20ACZP.htm

One other thought, if you spend a lot of time cranking the engine without
it starting, you can pollute the crankcase oil with gas. So perhaps
you might pull the fuel pump fuses until it cranks normally.


Good luck, Bill



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Yeah, I checked and it had no codes @BB.

UPDATE: We just swapped the starter and it started right up(like really fast and strong), so for now the no crank or start issue is resolved. Changing the starter was really easy took less than an hour w/ my son and I, I was all worried about that top bolt from reading forums and watching videos.

Will need to keep monitoring to see if the warm start issue is still present and then chase it down using the many great suggestions I have gotten on here.
Thanks for your input.



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Hi Again,

I know about that top starter motor bolt from my 740, the trick was having a stubby swivel socket, maybe a 19MM. Otherwise the bolt head and socket etc jammed against the firewall.

Can you see what failed in the old starter? Can you do a DIY repair?
It seems that you can buy a complete starter cheaper than just a starter solenoid.
That seems crazy.

Good luck with solving the heat related bug, keep posting your findings.

Bill



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Warm start issue is still present.
Car starts but then stumbles, RPMs at 4-500, and stalls unless given a little throttle, then smooths out and drives fine.

Will start looking into all the items listed related to CPS,ICM,MAF,clean connections, etc...



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Glad the starter issue is behind you. For future reference so you don't get stranded, if the starter won't catch because of a dead spot in the windings or a sticky solenoid, you can often get it to catch by rapping hard on the starter motor a number of times with the end of something like a 2x2. Some mechanics will even get underneath with a hammer and beat on it. When I first encounter starter motor problems I start packing a 2x2 until I have time to replace the starter motor. On more than one occasion when out shopping and it wouldn't crank, I'd simply pop the hood, do a quick Fonzerelli on the starter to teach it a lesson, then now being able to start and drive home. Really impresses the passengers and bystanders.

Trying to think of more basics for you to check, based on what you just said about 400-500 rpm when still warm after sitting, I'm starting to wonder if the TPS on the throttle body could be on the hairy edge of being out of adjustment.

If the ECU doesn't know it's supposed to be maintaining idle then depending on how open the throttle plate is at rest and where the IAC valve is floating then your base idle without the ECU trying to adjust it may be down in the 400-500 range and it will indeed stumble and stall at that speed, even for an otherwise normally running engine.

With the engine warm and left to sit so it stumbles, shut it off without touching the gas to feather it out then check the TPS for an audible click as it moves away from the stop when opened by hand. It should not be set on the hairy edge of clicking, which is a distinct possibility with your symptoms. It might be clicking normally when cold, but when warm and allowed to sit may no longer be in proper adjustment. There is a spec inserting a feeler gauge at the stop screw where it's still supposed to click. A strip of cereal box paperboard inserted at the stop screw should still give a click when the throttle is opened. With the throttle normally closed, the throttle spindle (cable pulley) should not be up against its stop (otherwise the linkage rod needs adjustment). The throttle cable should also be checked to make sure there's a bit of slack.

Beyond your immediate stumbling problem, thinking of basics in general for a recent car acquisition, I wouldn't assume someone hasn't been fiddling around with the throttle body in previous years. I always start with a thorough throttle body cleaning on the bench (including the little vacuum port holes), checking the centering of the throttle plate, then properly readjusting everything to Volvo spec: the throttle stop screw (1/4 turn method, drop of paint so you'll know if someone ever touches it again), the TPS (click with the spec'd feeler gauge inserted, also different procedures for Bosch and VDO switches), the linkage rod to adjust the spindle stop gap, the throttle cable slack adjustment and kick-down cable adjustment (adjust to just before the pawl clunks against the bottom of the kick-down chamber down in the trans when the cable is plucked)). Double check that all electrical connectors (TPS, IAC and AMM), are clean and protected from moisture with dielectric grease, then fully seated. Make sure the flame trap is clean and the oil separator box isn't plugged. Tap solidly on the IAC with the end of a wood stick after it's been idling a few minutes during warm-up to see if the idle changes, indicating a dirty/sticky/worn IAC. With the engine idling, spray water (or starter fluid) around the throttle shaft to check for any change in running to indicate excessive wear at the throttle shaft. Inspect the accordion air intake tube carefully for splits, especially underneath. It all adds up to help with better engine operation and minimize the number of possible problems down the road.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now



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SUCCESS?
I removed the TB and IAC and cleaned them both, reset the TB/idle screws/TPS to spec(I have done this before actually using a write up from a few years ago, and I think its close but maybe a tad too open).
I noticed the smaller vac port at front of TB (that goes to canister I believe) was clogged, and also the butterfly was a only showing light through about 50%. I readjusted to show a full circle of light. The warm start has not occurred for past 5 days according to my son who has the car away from home.
The idle is a tad higher than my other 240's (1000) but I can always go back and tweak it just ever so slightly perhaps.

Thanks for all the tips.
I will post again if the issue returns after I look at the next items suggested.



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Hi,

The idle should be dead on the 750 rpm no matter if the air conditioning is on with cars that use an IAC.
That is supposed to be the beauty of the IAC with an electrical actuation.

You are either open too far on the throttle plate or butterfly plate, if it could bend in the middle. 🤫
A hinge mimics a butterflies body.😊
I have seen that type of air limiter where one side is spring loaded to close softly into the bores on carburetors or for choke variations to match closer to air density characteristics affected by temperatures. Thicker colder air requires more spacing.

The stop screw is used here for a static setting.
I’m pretty sure if you see very much light or any it is probably too far open.
Air is thin and light and can go around things 🤭 including over dams.
With that thought, there needs to be a tighter fit up within the bore.

The whole idea is to reduce air flow BELOW the upper limit of the IAC’s operating range so it does the higher idle function.
Today it’s reversed.
You set the air screw for a closed position so it doesn’t allow the cable pulley operating spring to apply excessive pressure.

On the older 240s there was a black adjustment screw.
It was used to set the lowest end of air bypass with the stop screw.
A wire was grounded to stop the IAC from opening completely in one direction.
Those earlier IACs had three pins for moving the valve each way of plus or minus.

The later models use only two pins to open the IAC against an automatic spring loaded return.
This became necessary for control simplicity and for ALL the fail safe reasonings you can muster up!

Phil



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Glad you're making progress.

Idle up at 1,000 confirms your suspicion that the idle stop screw isn't properly adjusted and the plate is a bit too open, either that or the IAC has an issue. To confirm it's not the IAC, do like I said and rap on it while running to see if the idle immediately drops down to normal. A slight drop in idle is semi-normal for an older TPS, but a drop of like 100 rpm is a sign of a sticky/dirty/worn IAC.

You said you were using an old writeup to adjust the throttle body. If it wasn't one of my writeups and talks about using the idle stop screw to adjust base idle to a set rpm with the IAC forced closed then that's old thinking from the LH 2.2 days. The preferred method for LH 2.4 (and LH 3.1) is the 1/4 turn method I mentioned (it's in the later and superseding Volvo tech bulletin I have on LH 2.4 throttle adjustment specs and was confirmed some years ago by a Volvo Vista Master Tech here). Ideally this is done on the bench, but you can do it on the car. With the linkage rod disconnected and the TPS loose, loosen the nut and back off the idle stop screw. Now with your fingers inside the throat holding the plate firmly closed, advance the stop screw until it touches and to the point it's just about to start moving the plate, then advance 1/4 turn more and secure the lock nut (followed by that drop of paint as the security marker I mentioned, nail polish even liquid whiteout works fine).

Now properly adjust the TPS. From my old notes which were based on the Volvo TP bulletin. "Adjusting the TPS: It should trip just as the throttle moves away from its stop so that the ECU knows when it’s no longer supposed to be controlling idle –you’ll hear a click and a click again on the return. You don’t want the TPS click adjusted right on the hairy edge, it needs a bit of tolerance. For optimal adjustment as determined by Volvo, proceed as follows. Start with the switch rotated clockwise away from the stop position. For a Bosch switch, hold the throttle plate closed, turn the switch counter-clockwise until it clicks then continue to the end of travel and lock in place. For a VDO switch, insert a .010" feeler gauge at the idle stop screw (if you don't have a suitable feeler gauge substitute two strips of medium heavy bond 24 lb. computer paper), turn the switch slowly counter-clockwise until the click is heard then lock in place."

Also, having to re-center the throttle pate is a sign the shaft may be worn in the bushing, usually the spring side, allowing unmetered air intake. Do a leak check as I mentioned.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now



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I have cleaned and checked the TB butterfly when we first got the car and checked all the vac hoses and accordion for cracks, etc.. but did not check IAC, vac ports in the TB, or the TPS adjustment yet.
Replaced the entire PCV since the oil separator had broken in 2 and oil was everywhere.
I will use the write up to check all these closer. I have had experience setting a TPS before (high idle issue that I resolved on my other 240)but did not suspect it until now.
it may be a few more days until I get my hands on the car again but will report back after going through this list of items.

I am glad you had suggested to check all this when it doesn't start and then to not let it start BEFORE digging into these items, hopefully I can address one item at a time until it starts and find the exact issue.



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Hi Dave!

Another excellent write up you have done here!
You covered everything I could think of.

I’m with you on the Throttle Position Switch and its adjustments.
The ECU needs the heads up on whether it should idle or speed up off idle.
The transition of air flow between the throttle plates flow change over needs to bet set into the range of the IAC’s movement. It can be a head scratcher until it gets blended right.

Again you put down a real good diagnosis of that being messed with.
The throttle bore and its vacuum ports are being cheated of their due respect when it comes to the EGR or fuel evaporation system. A bad hose to that thing doesn’t help matters any. I have found them rotted just out of sight or even disconnected from splitting ends.

A little wiping of the bore and spray can cleaner through the ports is playful maintenance that we all seem to forget or get lazy with.
🥴

Phil



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Have only had car for 3 weeks and have just been going over things and was planning on and chipping away at basic stage 0 but have been side tracked with this issue.
Looking through all the receipts that came with car it appears an aftermarket (ultra 12211 ?) starter was purchased in 2014. so i guess thats 10 years of cranking on it.



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The whirring sound from the starter sounds suspiciously like a bad starter solenoid. The solenoid isn’t engaging with the flywheel. Before replacing the starter, I’d check the condition of the red wire on the back of the starter. Make sure you have a good connection. That is the wire that goes to the solenoid.

--
Will I buy another Volvo??? We'll see....



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Check the battery ground also. on the body and the block. 1 in a blue moon it's not the battery nor the starter. Bad connection is possiblr.



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Hi,

I agree with Dave Steven’s assessment of an ignition system weakness or battery input voltage may be dropping out or down during cranking.
The ECU and ICU systems use very small and specific voltage signals and frequency waves to respond too.

How old is the battery?
Another question is has the battery ever set for a long time without a routine of being used.
Allowing a battery to sit too much drains years of service life away.
A float charger can help to reduce the sulfating plates in lead acid batteries.
In a week to ten days of non-use starts a downward life cycle.
In other new age batteries it’s darn dendrites!

The CPS is not something to dismiss lightly either.
Hard starting or idling rough and slow or a streak of light miss fires that seem like a rich or lean mixture can be from ill timing that is starting with the CPS.
They do degrade slowly and any frayed insulation is a definite heads up.
I pulled one coated with an oily grime. Inside it there was softened signal wire insulation.
Well below the shielding that doesn’t seal a thing.
Until you actually handle it and wipe it, it looked intact.
If it’s original get rid of it or even if it’s the second or third one (?) that helped put 295,000 on my 1991.

There is another middleman in all of this that gets ignored and it’s because it’s behind the battery.
The item is a spark relay the switches the ignition coil on and off causing it to work.
This item works when it gets signals from the ICU, that the CPS talks too. It’s a chain of events that takes a second or so to get going. And that’s when everything is nice and right on.

If you get to it, Unplugging helps sometimes by exercising the pins surfaces and apply dielectric paste.
Check the pins for corrosion.
If you have time, put fresh heat sink paste between the base and the transistor for summertime driving.
About every ten years under terrible environments keeps it happy.
I had one go bad that it shut down the engine real regularly like in 30 seconds after starting.
Your right, having a few spare parts cars available is my Cheshire Cat Smile! 😏

The ICU has to tell the ECU to turn on the injectors and fuel pumps, through a system relay, that also powers up the AMM.
Hesitation along any of those items above, extends the cranking times.
So, you have to follow a path of one orange wire in a schematic to see the circling of both systems.
The CPS, is the guy who yells out “the engine is moving now” and then the chain wiggles to tightens up everything to turn on!

It’s like you are in a dark closet and you know there’s a light bulb in the middle.
You just need to look or more likely “feel” around to make the chain links tight, of which, will come from knowing how it works. 😊

Good luck this weekend!

Phil



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Hi,

I agree with Dave Steven’s assessment of an ignition system weakness or battery input voltage may be dropping out or down during cranking.
The ECU and ICU systems use very small and specific voltage signals and frequency waves to respond too.

How old is the battery?
Another question is has the battery ever set for a long time without a routine of being used.
Allowing a battery to sit too much drains years of service life away.
A float charger can help to reduce the sulfating plates in lead acid batteries.
In a week to ten days of non-use starts a downward life cycle.
In other new age batteries it’s darn dendrites!

The CPS is not something to dismiss lightly either.
Hard starting or idling rough and slow or a streak of light miss fires that seem like a rich or lean mixture can be from ill timing that is starting with the CPS.
They do degrade slowly and any frayed insulation is a definite heads up.
I pulled one coated with an oily grime. Inside it there was softened signal wire insulation.
Well below the shielding that doesn’t seal a thing.
Until you actually handle it and wipe it, it looked intact.
If it’s original get rid of it or even if it’s the second or third one (?) that helped put 295,000 on my 1991.

There is another middleman in all of this that gets ignored and it’s because it’s behind the battery.
The item is a spark relay the switches the ignition coil on and off causing it to work.
This item works when it gets signals from the ICU, that the CPS talks too. It’s a chain of events that takes a second or so to get going. And that’s when everything is nice and right on.

If you get to it, Unplugging helps sometimes by exercising the pins surfaces and apply dielectric paste.
Check the pins for corrosion.
If you have time, put fresh heat sink paste between the base and the transistor for summertime driving.
About every ten years under terrible environments keeps it happy.
I had one go bad that it shut down the engine real regularly like in 30 seconds after starting.
Your right, having a few spare parts cars available is my Cheshire Cat Smile! 😏

The ICU has to tell the ECU to turn on the injectors and fuel pumps, through a system relay, that also powers up the AMM.
Hesitation along any of those items above, extends the cranking times.
So, you have to follow a path of one orange wire in a schematic to see the circling of both systems.
The CPS, is the guy who yells out “the engine is moving now” and then the chain wiggles to tightens up everything to turn on!

It’s like you are in a dark closet and you know there’s a light bulb in the middle.
You just need to look or more likely “feel” around to make the chain links tight, of which, will come from knowing how it works. 😊

Good luck this weekend!

Phil



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Well, it had a no start this evening, doesnt even try to crank.
Swapped battery and it made no difference.
Acts like a bad starter like it will 1 out of 10 times make a click but not try to turn over. engine was hot and so was the starter.

My son will try again in the AM and bring it home so we can swap CPS if it starts, otherwise we will tow, it.

I will digest all of your suggestions and examine each item in addition to messing with CPS.

Thanks!



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Well, it had a no start this evening, doesnt even try to crank.
Swapped battery and it made no difference.
Acts like a bad starter like it will 1 out of 10 times make a click but not try to turn over. engine was hot and so was the starter.

My son will try again in the AM and bring it home so we can swap CPS if it starts, otherwise we will tow, it.

I will digest all of your suggestions and examine each item in addition to messing with CPS.

Thanks!



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First thing I'd check would be residual fuel pressure. Without the means to test that, you might examine the vacuum hose to the fuel pressure regulator for fuel leakage from the diaphragm. If that isn't suspicious, pulling plugs might lead you to a leaky injector. What year is your 240?
--
Art Benstein near Baltimore

“Education is the kindling of a flame, not the filling of a vessel.” -Socrates



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hey, its a 91. I have checked the FPR vac hose once and it was dry, i will pull plugs and check those. Thanks



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Smells like the igniton side based on your description of it being a warm engine and needing to gun a stumbling engine and have it smooth out, also that all the basic of the fuel side check out. When was the last time the distributor cap and rotor were replaced? Check the ignition wires, especially for poorly seated or loose boots. When were they last replaced? Carefully inspect the CPS sensor cable for signs of damaged insulation, especially at the flex points at the standoff clips (unclip for inspection) and at the sensor on the bell housing (use a bright light and a mirror if needed). A failing CPS can act up when hot and cause a no-start, but allow a cold start.

If you ever get a full no-start condition, either cold or hot, there is a test you can perform at the OBD diagnaostic socket to check for a missing CPS signal (see the 700/900 FAQ here). Although I don't suspect this, another easy test you can do if there's a cold or hot no-start or it's running poorly is to shut the engine off, disconnect the AMM and attempt a restart into 'limp home' mode. If it now restarts and idles fine, albeit sluggish under acceleration, then that would point the finger to a bad AMM.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now



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Thanks for the tips, I will give all this a look and try and report back.



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