92 cold start stalling problem
eculbert
06-02-2006, 04:52 PM
Well, the saga continues. Egr seems clean/okay. 1.17amps, 10.1 ohms dvom amperage/resistance check, not sticking even the slightest. Valve seems to seal okay, mouth full of air takes about 20 seconds to leak past valve..insignifant amout.
NO codes on KOEO. I have no manual for other ideas. Should I have run codes with engine running?
Seems the 'truth' finally was found out on the way home, not that she lied, but maybe I didn't hear correctly, is that the symptoms 'disappear after a couple three blocks'. Bringing me home as my friend Wes's had been up approximately 24hrs at that point, I found this out from his sister. The car idles fine after a few blocks warm up.
The 'funny' thing is no codes. We, Wes and I, pulled the egr out and it wasn't stuck, the above readings were on a bench with a 12.1 volt bench electronic powers supply, not from the battery in the car. The pintle slams full up with the solenoid just fine (one/two seconds at 12v..just till the ammetter settled). The pintle slides smoothly up/down full distance with NO discernable friction. We put it back in with a new gasket.
She drove me home and had to restart it for the 4-way stop 4 houses away from startup, but then 1/2 mile later, it purrs like a kitten at all stops till we got home.
She said it started doing this 'last fall, just before cooler weather, then was fine all winter'. We live in Dante's inferno, er, Phoenix AZ area...should be at/over 110F today.
This is a strange one. No codes on key on, engine off. Been about ten years since I messed with anything 'compukerized', engine wise. Legally blind, cannot drive, stupid state still renews my 'identification card' as I now call it. Good till I go in at 65 and have to take eye test. May do it just to see if they still pass me...flunked it three times in april 97 and they still gave me one!! Duh, guys.
Serious question, what are the 'cold' range and 'hot' range for the gm/s10 temp sensors. I would like to ohm it cold and hot maybe tomorrow morn early if anyone knows what around 70 degrees and 180 plus values should be. Thinking flakey temp sensor now.
We replaced the pvc today with one from napa while we were at it.
She has had it in two shops, and one said the fuel pressures were 'fine'....hopefully he knows what he talks about.
Would love to 'fix it' as this family is sorta my adopted bro and sis...I spent several days up to my neck in grease on the 6.2 diesel Wes insists on driving swapping the grease bucket out in '02, but I can rely on either of them if they are available for help...very good friends.
NO codes on KOEO. I have no manual for other ideas. Should I have run codes with engine running?
Seems the 'truth' finally was found out on the way home, not that she lied, but maybe I didn't hear correctly, is that the symptoms 'disappear after a couple three blocks'. Bringing me home as my friend Wes's had been up approximately 24hrs at that point, I found this out from his sister. The car idles fine after a few blocks warm up.
The 'funny' thing is no codes. We, Wes and I, pulled the egr out and it wasn't stuck, the above readings were on a bench with a 12.1 volt bench electronic powers supply, not from the battery in the car. The pintle slams full up with the solenoid just fine (one/two seconds at 12v..just till the ammetter settled). The pintle slides smoothly up/down full distance with NO discernable friction. We put it back in with a new gasket.
She drove me home and had to restart it for the 4-way stop 4 houses away from startup, but then 1/2 mile later, it purrs like a kitten at all stops till we got home.
She said it started doing this 'last fall, just before cooler weather, then was fine all winter'. We live in Dante's inferno, er, Phoenix AZ area...should be at/over 110F today.
This is a strange one. No codes on key on, engine off. Been about ten years since I messed with anything 'compukerized', engine wise. Legally blind, cannot drive, stupid state still renews my 'identification card' as I now call it. Good till I go in at 65 and have to take eye test. May do it just to see if they still pass me...flunked it three times in april 97 and they still gave me one!! Duh, guys.
Serious question, what are the 'cold' range and 'hot' range for the gm/s10 temp sensors. I would like to ohm it cold and hot maybe tomorrow morn early if anyone knows what around 70 degrees and 180 plus values should be. Thinking flakey temp sensor now.
We replaced the pvc today with one from napa while we were at it.
She has had it in two shops, and one said the fuel pressures were 'fine'....hopefully he knows what he talks about.
Would love to 'fix it' as this family is sorta my adopted bro and sis...I spent several days up to my neck in grease on the 6.2 diesel Wes insists on driving swapping the grease bucket out in '02, but I can rely on either of them if they are available for help...very good friends.
eculbert
06-02-2006, 09:07 PM
I am a former electronics test tech....last century. Let me run this by you. If the coolant temp sensor has 'drifted' downward in resistance, then it would be telling the motor that it is now warmed up prematurely. Her gas mileage is slightly down and all also, according to her. It it is reporting a different temp than is actually there, then the engine controls would 'adjust' to the false reading.
It might not be enough to trigger any of the other sensors or its 'testing' but be just enough to mess things up especially right after startup. In the winter, it might be cold enough to trigger the cold start, but not when the motor is at around 70 to 90 or so like they are now in the morning. The motor 'seems' to run fine when run for awhile, but even then I notice just a tiny bit of 'rough' sound that I dismissed earlier.
I need to know what one of those temp sensors reads at 10 degree F intervals from about 70 to over 100F if possible on a 'good' system. if it is telling the computer that the motor is over 125F and it is only 75, that would explain the weird early shaking and stalling. Can you see this.
It IS possible that that is what is happening. It might be just the 'low temp' end is not reading low enough but when the motor gets warmed up it is close to correct reading (hence that slight misfire I think I felt/heard from the motor). Saw this on a defective early vacuum egr on about a 84 ford motor... Semiconductors can, if something happens to 'alter' or shock them change values and make life miserable.
It might not be enough to trigger any of the other sensors or its 'testing' but be just enough to mess things up especially right after startup. In the winter, it might be cold enough to trigger the cold start, but not when the motor is at around 70 to 90 or so like they are now in the morning. The motor 'seems' to run fine when run for awhile, but even then I notice just a tiny bit of 'rough' sound that I dismissed earlier.
I need to know what one of those temp sensors reads at 10 degree F intervals from about 70 to over 100F if possible on a 'good' system. if it is telling the computer that the motor is over 125F and it is only 75, that would explain the weird early shaking and stalling. Can you see this.
It IS possible that that is what is happening. It might be just the 'low temp' end is not reading low enough but when the motor gets warmed up it is close to correct reading (hence that slight misfire I think I felt/heard from the motor). Saw this on a defective early vacuum egr on about a 84 ford motor... Semiconductors can, if something happens to 'alter' or shock them change values and make life miserable.
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