Mechanics

STALLS AFTER STARTING AND WILL RESTART BUT STALLS IMMEDIATLY

1996 Jeep Cherokee • 160,000 miles

The jeep was run hot and also had a blown trans coolant line, lost all trans fluid. The reason it was run hot is it also blew a hose, lost all coolant in radiator. What I did was fixed hoses, put all frah fluids in, gave the jeep a tune up. Seemed to run fine for a day. Then it started to die at stop lights or when it idled down at a stop, now it starts and dies starts and dies. Any ideas?
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Wert_dw
July 30, 2012.




Check compression and oil look normal? Any white smoke from exhaust? Fuel pressure good?

Docfixit
Jul 30, 2012.
No smoke compression good. Fuel pressue good. If I give it a little gas it will run as soon as you let off it dies. Will start back up but wont run without a little gas

Tiny
Wert_dw
Jul 30, 2012.
Suspect problem with Idle Speed Control Motor on Throttle try removing and clean pentile and passage ways

Docfixit
Jul 30, 2012.
Did that, wasn't bad. Now it starts and runs until you give it gas, then it backfires and stalls

Tiny
Wert_dw
Jul 30, 2012.
Did you recently disconnect the battery?

Caradiodoc
Jul 30, 2012.
No I did not disconnect battery. Now the jeep won't start at all. Trys to but still won't I am going to replace the idle speed control motor and try to at least get back to where I was before I cleaned it.

Tiny
Wert_dw
Jul 31, 2012.
Before you waste money on unneeded parts, understand the automatic idle speed motor only affects idle speed. It will not cause the engine to stall except from the speed being too low. In that case it will start and run if you hold the gas pedal down 1/4".

I only brought up the battery issue because if anything was disconnected in the previous repair that removed power from the Engine Computer, it will not maintain idle speed high enough until it goes through a very simple relearn procedure. This is a real common complaint and fix.

Caradiodoc
Jul 31, 2012.
Yes and I appreciate all of your help sorry if I came across wrong. No the battery has not been disconnected. It wont start with pedal down, acts like its missing, starting hard etc.

Tiny
Wert_dw
Jul 31, 2012.
Now the jeep won't start at all. Wants to but won't.

Tiny
Wert_dw
Aug 1, 2012.
If it's cranking normally but won't run, first check for spark and fuel pressure. If either ONE is missing, troubleshoot that system. If both are missing suspect the automatic shutdown (ASD) relay isn't turning on. That is typically because a signal is missing from the crankshaft position sensor or camshaft position sensor. If you don't have a scanner, the best way to monitor the ASD relay is to test the voltage at any injector, the ignition coil, or either small wire on the back of the alternator. You should see 12 volts there for one second after turning on the ignition switch. That proves the circuit is okay and the computer has control of the relay. What is important is that voltage must come back during cranking. If it does not, one of those two signals is missing. Check for a diagnostic fault code to see if there's one to identify which signal is missing. If there's no related code, then you'll need a scanner to see which of those two signals is listed as "present" and which is listed as "no".

Be aware that testing fuel pressure can be misleading. The fuel pump will run for that one second after turning on the ignition switch but if the ASD relay doesn't turn on during cranking, the pump won't be running then either. That is an important clue, but that one-second burst at key-on will give the illusion you have fuel pump operation when in fact, you don't. The better test is to measure the voltage. Every injector will have one wire that is the same color. That is the wire to measure the supply 12 volts on during cranking.
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Caradiodoc
Aug 1, 2012.

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