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stall

DARKFLY

NAXJA Forum User
Location
utah
ok this happen the other day and cant figure it out. 89 limited 4.0 aw4 when i cane to a stop it stalled it didn't want to start (turned but no go). pushed it off the side of the road and then it started.
 
ok now on saturday it was having a hard time again go to step on the gas and no go pump on the gas and it would finaly go do you guys thinks its my tps?
 
If it will run normally at high rpm (like 2000 or higher), but stalls at low engine speed, then your EGR is dead (stuck open). Did you try speeding up the engine when it was running badly? If it is the TPS and you have an auto tranny, then you will likely notice some weird shifting at the wrong times in addition to idle issues. On my 1990 (same Renix ignition system as yours) whenever the TPS went out I got a high rpm idle, not a stall condition. I'm on my third TPS since new. I would suspect the CPS (crankshaft position sensor). If the CPS goes out, you will have no spark but the engine will turn over. It may be an intermittent problem at first, or die completely. Test is to check for spark, and to try the unplug/replug at the connector for the CPS, located on the rear driver's side corner of the engine, above the fuel injectors. The reconnect routine will sometimes get it to start if it is the CPS. How about other electrical stuff on the jeep? Did you have any weird loss of power to guages, lights, or other stuff? If so, then the ignition switch at the bottom of the steering column is burnt out, and loosing connections. Any more clues you can offer would help narrow it down.
 
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ok cps is only 4 months old from stealer no other noticable problems. shifts great runs great idol is at like 750 little flux but not bad when it did stall and start back up it went to 2000 rpm and then settled back after about a min to 750. i dont know what else it could be. it has new plugs, wires, cap, rotor, air, fuel filter, no vacume leaks, its just got me right now. it has yet to do it sence sat though i just dont know?
 
That occasional high idle points to TPS, but could also be other issues. Time to break out the multimeter and and check that the TPS signal is in spec (with automatic transmission output should be at 82% of input, throttle closed) and that you get a smooth change in output voltage as you rotate the butterfly shaft (move the throttle plate). On the Renix system TPS (up to 1990), the TPS is adjustable by loosening the mounting bolts and rotating it slightly to get the right values. A dealer can set it even more accurately by putting it on the diagnostic computer -if they have the setup for the Renix system. If it is intermittent flakiness, then it could be hard to find. If you have them run the diagnostic check, they can check the CPS signal too. The Renix system does not store codes, so if the sensor is not misbehaving when tested, then the problem won't show. You could also have the CPS wire shorting to the exhaust system if it touches the hot exhaust (melts the insulation), I would check that for damage also. Routing of the wire away from the exhaust is important - should go through the wire clip at the back corner of the engine, above the CPS.
 
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