Renix 4.0 starting problem
#1
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Renix 4.0 starting problem
I'm trying to help my buddy work on his 89 MJ, and we can't get it to start. It has spark, it has fuel. It turns over great, puffs a little smoke out the exhaust occasionally, but never fires up. The plugs are soaked in gas, like it's flooded.
We have a new distributor, new CPS, new MAP sensor, new coolant temp sensors, new TPS, new intake air temp sensor, new fuel tank and sending unit, good fuel and filter. Pretty much the only thing not new is the ECM.
Any ideas of what could be the problem?
We have a new distributor, new CPS, new MAP sensor, new coolant temp sensors, new TPS, new intake air temp sensor, new fuel tank and sending unit, good fuel and filter. Pretty much the only thing not new is the ECM.
Any ideas of what could be the problem?
#2
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Year: 1990
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This:
#3
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I'll try to clean it or replace it, already checked it for cracks and it looks fine. But I'll mess with it in the morning and let y'all know what happens. Thanks cruiser
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The vacuum line to the MAP sensor is fine. No cracks, no blockage, but we cleaned it anyway. Didn't make any difference, the Jeep still won't start. Any other suggestions?
#5
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Could it be that the distributor is crazy off and just needs to be indexed?
Differently sounds like a MAP problem and is just thinking that the throttle is wide open and dumping gas.... You could look at the intake manifold vacuum and compare it to the voltages the MAP is sending.
Those are my only thoughts though but what do I know haha.
Differently sounds like a MAP problem and is just thinking that the throttle is wide open and dumping gas.... You could look at the intake manifold vacuum and compare it to the voltages the MAP is sending.
Those are my only thoughts though but what do I know haha.
#6
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Did you check for spark? Pull a spark plug, leave the wire attached, touch the ground to the plug and see if you see a spark while cranking. Must have fuel, compression, spark and air to run. You're sure the CPS is plugged in?
Did it run at all before you replaced all those parts? Sounds like something basic is wrong here. Coil could be bad but do the basic tests and stop replacing parts until you're sure you've found it.
Did it run at all before you replaced all those parts? Sounds like something basic is wrong here. Coil could be bad but do the basic tests and stop replacing parts until you're sure you've found it.
#7
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The distributor is indexed right, I've double and triple checked it.
It has spark on all 6 plugs. All 6 are soaked in gas. It has fresh gas, and everything is plugged in.
Last time it was running was about a year ago, it ran great then. Just got parked for the 4x4 conversion, which took a while due to budget, now it won't start.
It has spark on all 6 plugs. All 6 are soaked in gas. It has fresh gas, and everything is plugged in.
Last time it was running was about a year ago, it ran great then. Just got parked for the 4x4 conversion, which took a while due to budget, now it won't start.
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#8
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What about the grounds at the engine dipstick tube? Common to TPS, IAT, CTS, and MAP...........
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Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
The distributor is indexed right, I've double and triple checked it.
It has spark on all 6 plugs. All 6 are soaked in gas. It has fresh gas, and everything is plugged in.
Last time it was running was about a year ago, it ran great then. Just got parked for the 4x4 conversion, which took a while due to budget, now it won't start.
It has spark on all 6 plugs. All 6 are soaked in gas. It has fresh gas, and everything is plugged in.
Last time it was running was about a year ago, it ran great then. Just got parked for the 4x4 conversion, which took a while due to budget, now it won't start.
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#12
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Good news-Those dipstick grounds are important. Did you have the wires off that ground previously or did it just start acting up?
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Year: 1990
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