Stalling Problem Puzzler
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Stalling Problem Puzzler
My 1995 F250 (7.5 ltr) runs perfect except for a problem I have chased for a year. Runs great cold but when it is up to normal operating temp and you do the following the idle drops until it stalls if no throttle is applied;
Stop and allow the truck to roll forward at idle and it stalls
Stop or restart after warm and allow the truck to roll forward or backwards in gear or neutral and it stalls.
Only code I found was related to higher than expected voltage at the EGR position sensor.
I've learned to live with it but sure would like to find the problem.
Stop and allow the truck to roll forward at idle and it stalls
Stop or restart after warm and allow the truck to roll forward or backwards in gear or neutral and it stalls.
Only code I found was related to higher than expected voltage at the EGR position sensor.
I've learned to live with it but sure would like to find the problem.
Lead Driver
Joined: Aug 2006
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From: Sand Lake, MI
What code exactly, might be telling you the valve is stuck part way open. That cause a very weak idle as its sucking in exhaust when it shouldn't be. "Cold" might be rich enough overcome the effects.
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stalling problem puzzler
It is a new EGR and EGR position sensor. Found numerous vacuum lines that needed replaced but no other vacuum leaks. If I disconnect the speed sensor (new also) it doesn't stall. As soon as the speedometer registers going forward or reverse the idle goes away. Sometimes it recovers but will drop again and stall.
Lead Driver
Joined: Aug 2006
Posts: 5,670
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From: Sand Lake, MI
Ok I see directly related to VSS input rather then anything do with the motor.
Might be in the wiring itself between VSS and POSM for example, did you investigate the voltage issue at the EGR at all? might be related might not be but worth looking into.
Safe to assume the speedo works right, has steady needle, as you didn't mention anything about it.
Have you tried unplugging the RABS module, see if its input is causing a problem?
Might be in the wiring itself between VSS and POSM for example, did you investigate the voltage issue at the EGR at all? might be related might not be but worth looking into.
Safe to assume the speedo works right, has steady needle, as you didn't mention anything about it.
Have you tried unplugging the RABS module, see if its input is causing a problem?
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Stalling problem puzzler
The speedometer is steady until 68 mph then it tends to waver a couple miles per hour. I did buy a instrument cluster at a swap meet and put it in with no change. I took it back out since the miles were a bunch more than what my truck has on it. I did unplug the RABS and the distribution valve on the frame with no change. Just for kicks I just went out and checked the continuity between the TPS and the EPS (brown with white stripe). It was good. Is it possible the E4OD controller is sending or not sending a signal to the ECM after the truck reaches operating temp? Puzzler!
Lead Driver
Joined: Aug 2006
Posts: 5,670
Likes: 12
From: Sand Lake, MI
Just to be clear you unplugged the rabs module itself, box located behind the glove box?
Just for kicks I just went out and checked the continuity between the TPS and the EPS (brown with white stripe).
Not following ya there, no direct circuit running between TPS (trottle position sensor) and the EPS (elect press control sel) in the solenoid pack? The Brn-wht wire is reference voltage.
When it stalls out how does it act exactly, like for example sitting still with a manual trans, suddenly let clutch pedal up when in say 2rd gear without giving any gas? Abruptly kills engine?
Has the trans ever been changed?
Wonder if the MLPS might be coming into play some how, might be worthwhile measure resistance through it when in its various positions, park reverse N drive 2nd and 1st. If for no other reason verify it is correct a minute.
Just for kicks I just went out and checked the continuity between the TPS and the EPS (brown with white stripe).
Not following ya there, no direct circuit running between TPS (trottle position sensor) and the EPS (elect press control sel) in the solenoid pack? The Brn-wht wire is reference voltage.
When it stalls out how does it act exactly, like for example sitting still with a manual trans, suddenly let clutch pedal up when in say 2rd gear without giving any gas? Abruptly kills engine?
Has the trans ever been changed?
Wonder if the MLPS might be coming into play some how, might be worthwhile measure resistance through it when in its various positions, park reverse N drive 2nd and 1st. If for no other reason verify it is correct a minute.
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Stalling problem puzzler
I think my abreviations are way off. The link I checked is between the TPS and the EGR position sensor. It shows continuity. Trans has never been changed out. I did unplug the RABS behind the glove box.
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howman442
1987 - 1996 F150 & Larger F-Series Trucks
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Apr 17, 2005 05:31 AM
