|
|
|
Hey all, I've got a problem that I've been trying to figure out since I bought this car. It's a 93 245 LH 2.4. The car is really difficult to start when cold, (by cold I mean engine, not ambient temp, I live in FL) this is only the case ocassionally as sometimes it starts right up first crank no prob . Once out of desperation when it wouldn't start after about 20 cranks, I held the pedal to the floor and it started right up. Also I think it's worth mentioning that after the engine is warm it starts up easily, I get pretty decent gas mileage and I ran dtm#3 for the fuel injectors and iac, everything checked out. The obd is giving me one code in slot 2, 232. No code in slot 6. Also after all those attempts to start my plugs were soaking wet w fuel.. Could this be from repeated cranking? So I'm at my wits end here, I'm leaning toward tps or engine computer, possibly ignition control module? Once the car is started it hesitates a little when the gas is pressed down, but like I said when she gets warmed up she runs like a Swedish dream!
|
|
-
|
|
Given what you've said, and given what you've accomplished so far, my first approach would NOT be to suspect some electronic failure. What I would do, with a 93, is check the fuel pressure after the car had been running and cooled off for 1/2 hour. Simply put, with the car shut off, I'd grab a stick type tire gauge and press it firmly onto the Schrader valve under the fuel rail and expect to see at least 15, maybe 20 psi. I'd wear my gloves and goggles of course, because some of this fuel will spray out when I release the gauge, but I will know whether the check valve, fpr, and all four injectors managed to hold the fuel pressure over a half hour and not dribble it away, possibly into the intake manifold if it happens to be the service injectors.
If after doing that, I didn't have any idea what to do next, I'd probably post the question to the board.
--
Art Benstein near Baltimore
Fifty-one years ago, Herman James, a North Carolina mountain man, was drafted by the Army. On his first day in basic training, the Army issued him a comb. That afternoon the Army barber sheared off all his hair. On his second day, the Army issued Herman a toothbrush. That afternoon the Army dentist yanked seven of his teeth. On the third day, the Army issued him a jock strap. The Army has been looking for Herman for 51 years.
|
|
-
|
|
|
Ahh I see, if the diaphragm is bad the fuel would leak past it and into the tb/intake. How long would the fuel rail ect. hold that pressure for?
|
|
-
|
|
|
No, you already checked for a ripped diaphragm, didn't you? That would have been the first suspect.
--
Art Benstein near Baltimore
An elderly looking gentleman, very well dressed, hair well groomed, great looking suit, flower in his lapel, smelling slightly of a good after shave, presenting a well-looked-after image, walks into an upscale cocktail lounge.
Seated at the bar is an elderly looking lady.
The gentleman walks over, sits alongside of her, orders a drink, takes a sip, turns to her and says, "So tell me, do I come here often?"
|
|
-
|
|
|
The psi was around 20, Not sure how to check the diaphragm, other than checking the vac hose for fue.
|
|
-
|
|
|
By starting with the pedal to the floor, leads me to believe it's flooding out. Needs more air to mix. I would be leaning towards fuel pressure regulator.
--
Post Back. That's whats makes this forum work.
|
|
-
|
|
|
just a thought, if it is the FPR wouldn't the no start happen every time, not just when the engine is cold?
|
|
-
|
|
|
I think you might be correct in thinking the FPR is not doing it. That's if you would like a second opinion?
I would lean more for a bad ECT or its wiring connection being bad because a high resistance reading would tell the ECU to increase the pulse width on the injectors there by making it richer.
It may not be much of a width change but IS when the engine is cold. It still can be higher in resistance even when warm but a richer running engine in winter will be hard to detect gas mileage wise or by noticeable power gain or loss.
If you drive it hot more miles than you do just warming up and shutting down for short trips the plugs should be running clean as they would normally. Try reading the plugs for a clue to the mystery story!
Best thing to do is to check it resistances at the ECU connector, when cold and then hot. Use a Bentley reference chart. Low ohms hot and high ohms cold. Examples is, Like 3 to 400 hot and 2300 cold. Depending on what cold "is"...? Hot is a proven good thermostat!
Working in the door way is better than under the engines intake manifold. That way you knock out two possibilities of either one all in one stroke.
One pin is one side of the circuit and cars chassis or ECU ground might be another.
I would search for the procedure to back probe or remove it from the ECU and then probe the wires as someone out there knows better than I !
If you have to buy a sensor be carefully to get the right numbered/colored one for your car!
Happy hunting
Phil
|
|
-
|
|
|
Thanks Phil, I've been hoping to avoid this mainly cause my knowledge of testing the ecu is limited but I guess now is a good time to learn! I'll see what I can find out and post back soon.
|
|
-
|
|
|
Ok did some searching on the www and found everything I could possibly need to know about the lh2.4 here is the link
http://www.volvowiringdiagrams.com/volvo/LH%202.4/LH2.4%20Manual%20Complete.pdf
I only have one question about testing the ECT , like Phil mentioned the resistance is based on engine temp. I assume I can check the baseline ohms w a cold engine at the ecu but how do I test the ecu while the engine is warm? Do I warm up the engine, then turn off the car, unplug ecu, turn ignition on then check slot 13 (ect slot) for lower resistance? And furthermore should I check the wire to the ect as well to ensure similar readings?
|
|
-
|
|
|
Hi there,
I looked at the diagrams for the ECT connection and I see it as PIN number TWO (on the EKZ116 system) of your ECU. Its behind the right side kick panel.
The other side of the sensor goes to ground somewhere which could be on a pin at the ECU or the body of the car and up through the aluminum case of the ECU. One lead in pin two and the other to a ground should do it.
While you are under there could you tell us the last three numbers of the ECU? Just curious what Volvo was running in your car in the year of 93. Something like 951 or 933.
As long as you see resistance change within the range of the sensor chart you have the right wires.
Just to be on the side of safe, I always disconnect the battery's negative terminal anytime I pull connectors on large electronic boxes or air bag components.
Give all the little pins of the box and connector clips a "good look over" for corrosion and even symmetry in their mounting holes. That's mentioned in that diagram manual.
I usually take some LPS 1 and soak a "Q" tip and dab everything with a very light coating. The reason all of this stuff operates on around 5 volts or a resistance reading.
Mother Nature, she is at heart, a big bully and at these current levels it's like a frees pass on a basketball course. A slam dunk for humidity! Just imagine salt sea air or salted roads, no difference to moisture.
Doing this at the ECU will be checking the wiring to/from the sensor let along the sensor operation itself.
Look at this as good work done even, if its not the issue!
Phil
|
|
-
|
|
|
Tested ect, ohms were within normal limits (tested Warm) I could actually see the ohms climing indicating drop in temp. Last three numbers on the ecu are 951.
Bit of bad news, tried to start the car afterwards. It won't start. I made sure the ignition was off while testing the ecu, even disconnected neg batt cable. My main fuel pump isn't priming the fuel rail... I was able to jump the main pump from the fuse box and that allowed it to start for a few seconds. Is I possible I messed something up? My relay possibly.. Either way thanks for all the help, I've learned a great deal more about the ecu today.
No I don't have the Bentley manual.. I am a student who pays way to much for textbooks as it is. One day though!
|
|
-
|
|
|
I seriously doubt you did any harm to the ECU.
What you may have done is scared something. You might be that close!
Since you were down there yanking on the harness you may have wiggled a common ground point connection or shook a bad something!
The relay you speak of is right down there on that harness. Your instincts may be telling you something.
You did not mention if you hear a hum in the dash area in front of you when you first turn the key and before cranking. That is a pre-pumping mode of starting up that was new with the nineties cars.
I do not what all the hums are about but it might be worth noting the next you crank it. Especially, after the battery was disconnected.
I am trying to assemble clues, for all, to think about! Someone KNOWS what I am babbling about!
Also, that relay is controlled by the ECU/ICU and CPS communicating. If you are losing the ICU trigger momentarily that might explain a flooding LIKE symptom, as in no spark moments.
How old is the CPS on this car, by the way?
The system relay use to be white in color. It's up by the ICU under there. They are known to have circuit board problems (bad soldering of the traces) and also the connector they plug into can be too!
There is a wire that comes off that connector that goes to ground point, for the relays pull in coil. I think I have seen one wire come out of the loom, somewhere to the left, going back towards the engine. It might, be the one but that might part, can get pretty BIG easily!
I have read that the female spade terminals inside there can weaken, loosen or even be CORRODED sometimes. Say you live in Florida heh?.....? Nice clue!
Now I know why, you attempted to clarify to us what a cold "ambient" temperature was! The clue now is:
Not close to Minnesota or halfway to New York area even?
Your engine should be starting easier all the time down there!
You might want to investigate that whole affair visually and with you ohmmeter to check for good continuity.
Wiggle things with leads plugged in and be aware of droops in resistance readings.
You can open the relay cover and manually close things and check the contacts for burning. Also, Reflow the solder traces if you have a small pencil type 25 to 40 watt soldering iron.
All of this, just happened, afterwards, may not be just a happen stance.
You ruled the ECT is providing information. Low to high ohms is a good sign. Now we know it connected all the way out there underneath the manifold.
You had a symptom change....sort of? If it stops being intermittent, this means you are scaring this gremlin, to stay in one place and it will jump out at you!
Phil
|
|
-
|
|
|
Cps isn't brand new but looks like its in fair condition, and I have spark. The only noise I hear when I turn on my ignition (usually) is the hum of the fuel pump priming and my relay clicking shut, except for now all I hear is the system relay.
Using the 2.4 manual I found today here is what I tried.
On the system relay receptacle jumping slot 30 to slot 87/2, I believe this is supposed to run the main pump? It does not
Also I ran ground to slot 21 on the ecu harness, which closes the system relay (this works), as well as running ground to slot 20 at the same time this also Is supposed to run the main pump.. It does not.
Jumping from fuse 6 to 4 will operate the main pump, and the car will run when this is performed
Fuel pump and filter are both bosch and 1 month old
The system (fuel pump) relay is very new as well and shows no sign of overheating or burning.
I think you were in the right track when you mentioned reflowing/knocking wire loose.. I'm just hoping the ecu isn't kaput.
Thanks Phil you've been extremely helpful.
|
|
-
|
|
|
I do not have time at this very moment to look up on diagrams what you are doing.
I know the ECU grounds one side of the relay to turn it on. The ECU in most cases grounds things to do things.
You may not have power on to the proper side of the relay socket from the ignition switch or some other source.. Check Arts web site Cleanflametrap.com. He may have some ways to check that out on there.
Phil
|
|
-
|
|
|
For testing resistance of the ECT there's no need to turn on the ignition. Other than that it's exactly as you say.
For your other question, getting to the head of the sensor for testing is a pain, which is why people opt to test from the ECU connector.
Spencer
PS Do you own a copy of the Bentley?
|
|
-
posted by
someone claiming to be Walter Lamar
on
Thu Feb 27 09:34 CST 2014 [ RELATED]
|
|
Hi I have a 1990 240 DL 375K with all the same simptons like your car ect. and I swapped the ECU with a recommended Pn# 0280-000-951. The car has started ever since . All the codes now read 1-1-1 .
|
|
-
|
|
|
Intresting, I'll keep this in mind, thanks.
|
|
-
|
|
|
That is interesting to note while looking for an answer to symptoms like these.
This is not the first time I have read this on the board but at the same time, I have read, it turns up to be something else. A system relay, CPS or in the case I had once, a very suspicious connector terminal on the main fuel pump itself.
I pulled the pump thinking it might be going intermittent and was testing the newer one I had put in, with the jumper from the fuse panel, with a flip switch, it also fail to tick over too. I still think it was the pumps connectors.
I have also picked up a 933 to keep on hand. I put it in to test it in the case I had to take it back to the P&P. It is still in the car. I cannot tell any difference between the 561 ran as both handle EGR's.
Does the 951 work with EGR's or is it , by chance, just for automatics transmissions? I heard back on the 83-84 years they did tricks like that with the engine compartment mounted ignition modules numbers!
I am hope in this posters case it's the ECT sensor, the connection on the sensor or the ECU pins might be corroded a tiny bit somewhere he might find. He might luck out and by just pulling them on and off might clean them enough into working again, temporarily.
I'll cross my fingers on that but no way will I do my toes on this one! (:-) this is not good sandal weather. (:-)
In his year car, a 93, I would hope it has already got the 933 or 951 installed. I like to blame the black boxes last as there are to many go betweens in the whole system.
You interest in bringing this up will be appreciated, as its food for thought, for all!
Phil
|
|
-
|
|
|
Don't if it's the FPR, but aleekat is onto something. The mixture is probably too rich. By flooring it when you start you are closing off the fuel supply to the injectors.
|
|
-
|
|
"By flooring it when you start you are closing off the fuel supply to the injectors."
That's a new one on me. How is this injector fuel cut off accomplished?
--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
|
|
|
I have to agree, normally throws more air.
--
Post Back. That's whats makes this forum work.
|
|
-
|
|
|
So by flooring the pedal when starting, Im closing off fuel supply to injectors? I was surprised flooring the pedal had creed any change, considering the fuel injection. Anyone know the ohms for the TPS?
|
|
-
|
|
|
Ah yes the fpr, mainly out of not wanting to buy a part if I didn't need it I checked that as well. Vacuum is strong and there is no fuel leaking out of the vacuum side of the fpr while it is running no fuel in the vac hose either. I read someone's thread saying that if the vacuum line smelled like fuel at all that means it is bad. Any truth to this? I figure if it's job is to pull neg pressure on a fuel diaphragm there is a good chance it will smell like fuel.
|
|
-
|
|
|
Yes to the vacuum line smelling like fuel. Another thing to consider, ECT. If it senses(either real or false) really cold temps, tells computer to dump more fuel. You may check wiring to, the connector, etc
--
Post Back. That's whats makes this forum work.
|
|
-
|
|
|
Mkay I'll order a new fpr and see what happens
|
|
|
|
|
