Hey guys,

Just wanted to get some opinions. I purchased an 88 240 wagon from the original owner with pretty low miles (130K) as a daily driver because my truck is horrible on gas.

Last fill I hand calculated and came up with 17-18mpg. That seems low to me for this thing. Im not expecting 30, bug maybe mid 20's at least.

Things I have replaced since I bought it include...cap...rotor...plugs...wires...o2 sensor...air filter...and fixed my OD. I recently did the o2 sensor, figuring it was the original and maybe a little lazy, but it doesnt seem to have affected my consumption.

What else can I try here? I am still battling this wierd lazy start condition after sitting, but I havent figured that out yet. I have replaced the FPR and I will try the FP relay next. I verified that the in tank pump works when power is applied at the fuse box, but maybe it isnt going on with the key in the on position.

I just think that the car should have a little more milage in it.

Am I wrong?

1988, yay? So you got teh Bosch LH-Jetronic 2.4. Doood, you may very well have teh OBD-1, the OnBoard Diagnostic,

http://www.brickboard.com/FAQ/700-900/EngineOBDCodes.htm

So you have loacted and now know the part number label on your Bosch LH-Jetronic box.

So then we looky here.

http://www.nuceng.ca/bill/volvo/database/ecu.htm

(Please note no Bosch EZK ignition computer box part number label listing as these correspond with the LH-Jetronic part label PNs.)

If you have teh Bosch 2.4, use the OBD diagnostic feature and get all fault codes. Repeat until you get no more using BOTH socket 2 (fuel LH-Jetronic) and socket 6 (ignition and EGR, if so equipped).

So see here at http://www.brickboard.com/FAQ/700-900/EngineOBDCodes.htm

Perform the test and record the codes.

If you have Bosch 2.2 and owlder then you have to use a multimeter to test the sensors AND the wire harness continuity. These is a test function also with using a test light so it blinks in response to test input. The method is around someplace.

IN some instances, such as engine coolant sensors, these can start to fail and the Bosch LH-Jetronic and Bosch EZK will put up with it until it is truly failed, so you may get poor fuel economy and emissions (too rich or too lean).

Anyhoo, man, check the OBD codes.

Far out.

Happy God Damned Holly Jollidays, er Jolly Holidayze.

Dude.
--
Far out, man.

The only thing I'll add here is that usually you can pick up about another 4% using 100% synthetic lube. That's engine, transmission, and rear end. I'm an Amsoil kind of guy, and there are certainly a lot of other products out on the market. My 85 245 automatic gets around 21mpg around town, so I think you're right in the ballpark.

Machineman has hit most of the nails right on the head.
As old as the car is, I'd spring for an engine temp sensor. Make sure they sell
you the correct one, they are different between adjustable mass meter systems and later nonadjustable. Unless you can see it closing the heat flap in the air filter housing, chuck in a new thermo bulb.
240s have real brake calipers, not sliders, and don't tend to stick a little. Frozen pistons or an internally failing brake hose can make them stick A LOT.
Don't know if the electric speedometer cars are subject to cracked odometer gears like the mechanicals.
Also haven't seen anybody mention size 15 right feet. Driving habits can make a lot of difference. Can't "drive it like you stole it" and get 40 MPG.
Old fart newby, Carl.

Automatic or Manual? Autos won't see over 24-25mpg at best, more like 22 mixed and <20 in-town. My stick 240 got about 25mpg on the highway without working overdrive, and I expect it would have gotten at least 28mpg with OD working.

So, if it's a stick, too low. If it's an auto it's not that low.

The hard start and low mileage make me think you have an intake leak. How are the vaccum lines? Are they all attached?

"The hard start and low mileage make me think you have an intake leak."
And the place to look is the intake manifold gasket.
Check the plugs, if one is different it is the gasket.

Also I somewhat disagree on the mileage claims. My 91 automatic gets 26 hwy, admittedly maybe a different LH system, my 93 manual gets 28-29 hywy both at about 70mph.

As you say I would look for the hard start problem first.
Do you have a way of checking fuel pressure? The gauge is not too expensive and well worth it. You can check the running pressure, but also the whether it holds pressure after shut down. Critical on cars that do not turn on the pump initially.

As you say there is no start injector, the ECU lengthens the injector period on cranking to inject more fuel. You can check this but it requires a 'scope.
--
93 245 Classic, M47, IPD, 91 245SE AW70, 89 745, M46, IPD, 89 744 M46 IPD, Dependents-00 S/V 40s

You should check your o2 sensor to see if it is functioning properly. I use a digital ohm meter. My 88 wagon gets 23.5 to. 24 in town and 28 driving just right on the interstate. My 90 5 speed can get 32 on the highway driving right and never less than 26 in town.
I have no idea why.

I put a brand new o2 sensor in the car last week. Havent noticed a difference. I put 50 miles on the car with a full tank and im already missing a 1/4 tank.

I would really like to get this hard start figured out first honestly.

I would not have expected the O-2 sensor to do anything appreciable either! It works after it goes closed loop.

We need to find out if the injectors are firing as soon as you turn the key to three and that cranks the engine over. You know bump the starter and see if it sprays.
As soon as you do the injector test you can put them back first.

Need to verify the IAC goes full open! You can leave them both hanging out and loose to observe them since you have no plans on running the car, just bumping into start mode.

A normal IAC will rev the engine past normal idle every time it starts and then lower it back just as fast if its working correctly.

You can pull the coil to distributor wire off and put it somewhere near the drivers fender held up away from a ground by a quarter inch. I say this to keep it away from any gas or fumes that might be lingering on the engine from the last test. You want spark immediate-- MO!

If all this come on in a blink, at the same time, then we have to assume it is a timing problem or an overactive or leaky start injector may be affecting mileage in a combination maybe?
You are using too much gas or your neighbor is riding his lawn mower an awful lot! (:-)

A compression test and reading the plugs from time to time might help isolate the running condition of the engine.

What do you think are you IN?

Phil

this car doesnt have a cold start injector.

Hmmm, I did not think they did away with those until after 1991 models years!

Did you remove it or a Previous Owner?

I think this way as I relate the ECU's changed from the two colored 561's, pink labels being bad, to 933 and 951's.

What does your car have for an ECU?
Phil

I dont want to start sounding ignorant now, but where can I find the ECU?

The ECU is behind the plastic panel that is in the footwell of the front passenger side. It is just forward of the hinges that hold the door.

You have to pull up the threshold plastic cover and pull loose the clipped on trim that goes up from the threshold to release that plastic cover.

Look and see what number is on the ECU and what color is the label.

Post back what you have. There are ways to check things from that harness connection.

Phil

So guys, the hard start after sitting has seemed to intensify itself. Now, if its sits and I come back out, Ill have to crank for minimum 30 seconds while pumping the pedal to get it to fire. I have jumped the pump fuses in the panel to see if its a delivery problem and this DOES NOT help. I picked up a CTS but its been snowing here A LOT lately and I havent gotten around to it. I dumped some dry gas in the tank thinking maybe the fuel was freezing with the ethanol gas around here, but that didnt seem to help. Once I get this CTS in Ill report back.

Is there any easy was to get this sensor in? I really dont want to drain all the coolant. I may play russian roulette and try to do the quick switch-a-roo when installing the new one.

It appears that colder weather may have helped intensify the issue.

Very well could be that rear engine coolant temperature sensor not telling the ECU to increase fuel amounts on the injectors.

Were you able to identify the type ECU you have? Since you do not have a cold start injector I am curious what's in there myself.

When you run the pumps that should have reduced the crank times. If there was a problem in them providing fuel quick enough to fill the rail.

This getting colder issue, plus the lower than you think you should have fuel economy, might get explain itself in that one part.

Yes keeping the coolant system air bound, is like a finger over the end of a straw. It will hold the coolant in the block for the switch-a-roo!
I read recently that a deep socket no longer than 2 3/8" long will fit under there. I believe he said he got it at Walmart but I thought they only sold sets.
Just something to think about using or see if you have one. The size I do not know but you have a sensor in hand to answer that one!

It's a small hole unlike the thermostat housing fitting. Very hard for it to burp to let air in and no air pressure above it to push it out. The water gets "hung" between the balance of no pressure or a vacuum and gravity with the weight of water.

Good luck on your mission!

Phil

Its great to have an open dialog with people who know what Im looking at. When I ditch this cold, Im going to replace the CTS. Im hoping that fixes it. Crosses fingers!

Well guys, I swapped out the CTS. Im not sure it made a difference. The first time I went to start it, it hesitated a little. I had to hit it twice for it to start and even then it stumbled until I gave it some pedal. Ive disconnected the battery to see if I had stored codes that I could erase with the new sensor in there, so we'll see how it goes.

Continuing on, after my test drive to make sure the new sensor wasnt leaking, I decided to check the plugs and compression. Of course one of the plug ends broke off my new set of wires ;(. Thank god they are lifetime warranty. I just swapped one of the old wires a saved onto it until I can get back to the part store.

[IMG]http://i134.photobucket.com/albums/q93/krajus83/20131221_121245_zps7291c4c4.jpg[/IMG]

They all look uniform, nothing out of the ordinary except maybe a little lean...would like to see more of a tan.

The compression numbers are as such...

1-175
2-176
3-167
4-185

I'm thinking maybe some carbon on the rings or something, but nothing crazy different in numbers. Nothing crazy horrible...

I do notice more blow by with a cold engine, but that is normal. Once its up to operating temp a lot of it goes away.I can rest the cap on the VC and it doesnt shoot off. It rattles around a bit, but nothing crazy. There is a little pressure there, but again, nothing crazy.

What do you guys think?

I agree the plugs look pretty much normal. Three of them are using a tiny bit of oil or are slightly lean running like you said. The first plug on the left looks like it a little too clean with those speckles or there is just more light on it. Keep that cylinder in the back of our minds.
From what I can tell there is nothing to do about any of them. The porcelain looks good so there does not look like there is a detonation or timing issue.
Compression looks to be very typical.

I am curious though of how the IAC is responding when it does start.
Like I have said the engine should fire up quickly and rev up past it's normal idling rpm. It then should drop back to idle every time you start the car.
If the throttle plate is open to far (stop screw in too far) then you are cranking in too much air from the get go. You should not have to touch that pedal if it's set right. IMO the tighter that plate seals off at idle switch setting, the better. You want the IAC to have the control.

The IAC and the ECU will be confused for a split moment of what to do. The horse is hooked up to the carriage but there was slack in the harness and reins.

Just trying to place what might be the hesitation. You stated or insinuated that it cranked less before it hit. That's progress, I think.

Phil

Progress maybe, It went back up into the 50's today. A far cry from 13*. I guess Im going to change the fuel filter tomorrow, then order a throttle body gasket and go from there. When I pull the intake and everything off, Ill give it a good cleaning.

I am assuming that valve underneath the intake that says Bosch on it is the IAC? I did unplug it today trying to fish my bear hands back to that CTS. Once I pull the intake tube, ill pull that business off too and clean it out. If I hit a yard this week, Ill pull one of those too and swap it on.

Do these things have a crank sensor? Maybe the sensor is dirty or not reading as it once was and needs replaced. Is that common on these?

At least once I have this figured out ill have a pretty reliable car.

-Justin

If you do not have wires coming out of the bottom section of your distributor, then you have a CPS be hind the head.

Earlier models with hall sensors have wires to connect to it inside the distributor.

Yes the IAC is down there. One hose runs from the accordion hose to it. Another hose runs from the IAC and goes up to the back of the intake manifold. It's intended to bypass the throttle plate entirely.

Are you thinking that intake manifold is leaking? That might explain the one plug looking a little different.

The throttle body is a simple device to clean and can be done fairy well on the car with a rag that is wet down with solvent. You just do not want any fluid getting the electric switch housing via the shaft.

If you pull all this stuff loose then you can shine a light on the back side of the throttle plate to confirm it is well centered and closing all the way shut. In most cases it does unless it's been tweaked open or man handled.
I barely crack the plate open, if any, myself. The stop screw is there just to keep the plate from jamming in the bore since there is spring pressure constantly against it. The aluminum housing is softer than the brass edges of the plate.

I am sure that if you get control of that air flow things will have to improve.
You need to define how the IAC operates now and note the difference when checked out during cleaning. It makes a big difference having it working to its capacity and not bypassed by a foot or a stop screw.

Happy tinkering to ya!
Phil

88= No CPS sensor or OBD as others havesuggested. Just ground the blue white wire on the open 2 prong connector by the battery /power steering res to ground/eliminate the IAC motor which doesnt not seem to be the culprit in a lazy start condition by any stretch.This sounds like it is all fuel related,lack of residual pressure in the rail. might have to spring for a NEW FPR as the used one you installed might have same issues? Being that it might be 25yrs old as well? Have you checked the timing ad timing belt yet to ensure its not off a tooth somwhere?

Not yet. I was planning on doing the timing belt soon. I was going to check into it then. I ruled out it being fuel because I primed the system during a no start condition and even after it was primed it still just cranked and cranked.

If the system is filled, cold and cap installed on the reservoir there will only be a little dribble of coolant as you change the sensor. -- Dave

Under the dash, behind the glovebox.

Exhaust leaks and restricted exhaust will have a effect on mpg.also tire pressure, Driving habits.

More specifically, exhaust leaks upstream of the Oxygen sensor can cause oxygen to leak into the exaust. The oxygen sensor detects this and the ECU reads that as a lean condition and enriches the mixture. Check exhaust manifold gaskets, gasket where the downpipe attaches to the exhaust manifold. Also check the downpipe itself for holes.

Did a little more tonight. I pulled the intake tube off and MAS. The intake tube had oil in it, but from the looks of this PCV setup that is normal. I actually went ahead and removed the flame trap. Blowby got much less. I ordered a new one, but until it come in, ill run without it.

I got some of that MAS cleaner spray and hosed the MAS down. Reinstalled it.

Car still doesnt like to start after sitting. Itll crank until i tap the gas and then it will start. I swapped out my FP relay yesterday, so that is out of the question.

Car runs great other wise. What else could this be? The TB was pretty crusty, but didnt have a new gasket to pull it. I guess Ill grab one this weekend and clean the TB.

Not sure what else to try. Injectors? I was thinking about grabbing a set from the yard and running cleaner through them on the bench. Applying power and working them with the cleaner in and then swapping those into the car.

Its getting annoying. I dotn want to keep trowing money at it. The fuel pumps seem to be working. Is there a check valve somewhere in the system?

I do not think you need to throw anymore money at the car until you find something not working.
You are asking good questions!

You say it cranks and hesitates to start until you depress the pedal.

You ask is there a check valve other than in the FPR.

Yes there is one screwed right on the end of the outlet of the main fuel pump, plus each injector holds fuel on the rail. Rest pressure is there for the short term but with any mechanical valve there might be a leak down point but NOT after zero pressure unless is really bad.
Then yes, they can empty the rail from either direction. The FPR could be considered in the middle of the fuel system.

When volume is lost the pumps have to run a little to make up any loss. On cars earlier than ‘91 do not have a pre-run pump up stage before the engine cranks. It takes a signal from the engine to start them where turning the key to the “II” does the trick on later cars.

I suggest the next time you try to start the engine after it sets that you jumper the pumps into running by using the fuse panel trick. Left side of 4&6 on your car I think?
This will fill up the rail. If it starts better, then it might be a show and tell moment!

If you do have a leaky injector then that might explain your need to prod the pedal with more air.

Now to throw a wrench is this thought!

The IAC may not be opening all the way when cranking and you are not getting enough air to begin with!
A dirty throttle plate, oil in the big hose means the IAC has received its due share of gunk too!

I feel for your dilemma! The leaky injector idea might explain some lack of mileage because the spray from it will not be proper.

Since you are thinking of doing that kind of labor.....
You could raise all the injectors up with the rail attacked and power the pump as mentioned before. Watch them with plastic caps or napkin paper taped under each. Gas evaporates quickly.

Can you tell what colors or condition your plugs are running? Have you ever done a compression check? I was just wondering if one cylinder is running oily or sooty. If so you can try running one heat range hotter plug in that cylinder for the oil problem.

Do you know for sure the in-tank pump is running? It’s another reason for the fuse panel jumper trick. You can find the how to information at CleanFlameTrap.com.

Doing some cleaning, sniffing and listening may be all that’s on order for this car, since otherwise, it runs great.
You might say, it’s like cracking a safe, the reward, is just an adjustment away! (:)

Phil

Phil. I jumped the pump terminals after it had been sitting and it still cranked and didn't fire. I'm startibg to think it might be in the intake tract somewhere. If fuel was bleeding down it would bleed down seconds after I just ran the pump.

Thoughts?

My thoughts are, I probably have too many of those for both of us! (:-)

I think we are thinking together on what is happening.

If the IAC is not opening properly that would choke the engine the same as too much fuel injected or leaked.

I notice you are questioning the thermostat which is good thinking.
I was thinking that too, but along with the ECT sensor for the ECU.

You see the ECU can only work with a properly heated engine like at 192F degrees called for in its program.

The gauge you see is only an electrically generated representation of engine heat.
The gauge is heated up to deflect the needle to some reference point that is numbered or not.
That gauge can be affect by ambient temperature of the cluster or dash of summer or winter but it is usually of an insignificant amount for an analog meter.

In our case, it’s not numbered, mainly because to do so will make for a more expensive gauge. The accuracy would have to be guaranteed to within some percentages to be useful. Even on most other factory cars that have the numerals they are too far apart to mean anything to the average Joe anyway!


The thermostat will have a swing differential with some overshoot and undershoot tendencies as they are mechanical. The less carefully made can be more noticeable over time!
The thing to do is to use a more accurate thermometer and compare the two readings for reference going down the road or over time during maintenance.

Extreme variance means either gas mileage, engine wear as sludge, pinging or worse yet head damage can result.

Now, that is one ticket, is that having and knowing the engine is where it’s supposed to be.

The next ticket is getting a reading aligned the same way to the ECU!
So it gets the best information on the combustion temperature short of probes in there. Not practical to do that one.
Coolant and the O-2 sensor are what we are dealt with to use!

So where am I going with this? Your complaints of having lower gas mileage, when there are posts of greater mileage.
Their engines might be running hotter than yours and in tune to its ECU better, is one point that puts your car at a difference. Of course there are the maintenance issues first and the human factors too numerous to mention to affect statistics lastly!

Are both of us, thinking of air flow...Yes!
Not enough air at idle means a richer running cooler combustion chamber despite the ECU dialing back the pulse width as much as it can.

You idle every time you coast or are stopped. The throttle switch tells on you or should!
The IAC changes and throttle movement tracking led to Changes in ECU programs over all the years of fuel injection systems. It has always been an issue of idling creates no mileage with emissions counted and added up within per miles traveled.

I think if you engine is running well but starts hard, the problems lie within that realm. This is my thinking or thoughts as I warned can be many.

You have fuel getting there but the ECU has no control of the air, what so ever!
If the ECU thinks the engine is just slightly cooler it enriches until the O-2 says HEY!
If the ECU thinks the engine is warmer it leans until the O-2 says Hey!
All is called Self Tuning, when IT IS closed looped! What if its not there?

We are back to starting it on its start and warm-up program. We have to adjust things to basic. To where, what is my air flow and what does the ECU need to know or expects to have, to fuel it!
The Temperature of the engine and the Mass of air with temperature and density defined.
Basic timing of spark, to the compression of the start mixture and we are done. Bang!

Starting the car from through an open window should be normal. No pedaling, that’s for bicycles!

Clean things and adjust is about as basic as it can be. Compare sensor outputs to verify what IS, IS as a Clinton cliché! (:-)

Keep working and posting. It a safe secret, until you open the door! (:)
Phil

Based on years of reading the BB, 240's (if properly maintained) usually get low 20's in town and mid to high 20's on the highway. A 5 speed can be capable of delivering 30+ mpg on a long highway trip. Depending upon season, my 90 240 did 20-22 in town and 24-27 on the highway. Once it even got 28 MPG and I was thrilled! IME - Your mileage is definitely low.

How does the car run? A defective cat or an undetected vacuum leak (such as the intake manifold gasket) will kill your gas mileage.

I was going to say FPR but you changed it. I would look for slight Drag on the brakes. It doesn't take much at all, to beat up gas mileage.
Check Inner E-Brake shoes as well
--
'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html http://cleanflametrap.com/tony/

Ill look into these things. Maybe Im getting what Im getting and thats it. I changed the FP relay with a spare I had just now to see if that fixed the starting issue. I dont hear the pump when I turn the key to the on position. But I can hear it once the car is running.

"I dont hear the pump when I turn the key to the on position.?

That's normal for the '88 (LH2.2 FI).
The so-called "prime cycle" started with LH2.4 in 1989 for the 240.

--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

You should be getting aound 25 MPG around town.

Check the timing of the Crankshaft with the Camshaft (and Distributor).
If there is a tooth off between the camshaft and crankshaft on the rubber timing belt it can affect performance a lot.

Also, put a timing light on it and check the ignition timing.

Check and make sure that you don't have any vacuum leaks on the intake manifold or vacuum hoses.
You can use a vacuum gage to check intake vacuum at idle.

Check the spark plugs for proper gap and condition.

Just a few beginners
steve

I was going to do the timing belt this month as its way over due. Plugs were gapped correctly when I installed them. No vac leaks that I know of. Ignition timing is on the money.

I like HillBilly's ideas better than mine for fuel mileage and starting.

I would also make sure the throttle switch is clicking when the throttle shuts and that the idle control motor is raising the idle speed up and back down right after it hits and starts.

That confirms the ECU is tied to a working IAC. It will also know to use it accordingly with the increased fuel mixture pluses needed to start and idle the engine.

The Engine Coolant Sensor affects mileage along with a properly working (Wahler) 192 degree thermostat.

Can you take a compression test to see how tired the engine might be?

I thought I would throw in the few extras he left for chapter two! (:)

Phil

I WOULD COMPLETELY FLUSH THE BRAKE FLUID & REPLACE IT W SYNTHETIC,,,tHEN CLEAN & LUBE ALL SLIDES & CONTACT POINTS,,
F THE BRAKES ARE ON JUST A LITTLE BIT,,YOU WILL NEVER GET GOOD MPG.IF THE FLUID IS OLD IT WILL HAVE IMPURITIES THAT RESTRICT THE PISTONS FROM RELAXING BACK TO THEIR CORRECT POSITIONS. mY 740 GET 32-34 MPG AT 70 MPH

25 MPG from an automagic around town miles is not going to happen in your lifetime no matter what you do to the car.

I tend to agree that 25 mpg in town is a stretch, but it depends on the urban density of the town. I live in San Francisco. Very dense. Stop sign on almost every other block. If I get 15 in town, I'm lucky. A spread out city with low traffic light density would give a different result. My car is an '87 240 auto in good tune. It's been getting 22 mpg + on the highway. I had never noticed the locknut on the distributor for setting engine timing, but when I had my timing belt replaced, I discovered the timing was way off. That greatly affected my gas mileage and overall driveability.

I don't think 25mpg around town is impossible with an automatic, but it is unlikely, and I would not count on it. I guess it depends on the "town."

I get more like 20mpg to (at best) 22mpg in town; but I also live in a town with - according to some studies - the worst traffic in the nation. But on the highway, I have seen right at the edge of 30mpg (this is with a 3.31 rear end).

I agree that 25mpg in city unlikely without serious tweaking.

My manual 240 in city driving Portland, Oregon got around 21-22. So I do think you have 2-3mpg more that could be obtained, although I don't know if this an automatic. See www.fueleconomy.gov to find out the re-adjusted data for your car to know what the ballpark is.
--
I own a Volvo or Does Volvo Own Me? Try the easy to search Expanded Style FAQ Index http://40mph.com/Brickboard_700-900_FAQ_Expanded_Index_Version/