mctod22

I have a 1990 jeep Cherokee Laredo with about 125k miles on it. Last week I got in it to go to work and it would not fire but the engine would turn over. The metal top of the rotor was broken and the nipple on the inside of the distributor cap was broke so I replaced both. still would not fire I replaced the coil still wouldn't fire jacked around with any connection I could think of and then it fired and drove normal for a week. Got in this morning same thing engine turn no fire checked cap and rotor were fine and didn't get spark from coil. Replaced coil and ignition module still it will not fire. Kind of lost for what next to try anyone have any ideas

VTJeep

prob the CPS...?? its a pretty common/cheap issue.

xj4life2

Change the CPS !!!!

mctod22

What is the Cps

mctod22

Is Cps crank shaft position sensor

mctod22

I just replaced crankshaft position sensor and still no fire any more ideas I'm at a loss

Slick761

..... man I hate to see you throwing parts at it. The two things I could see are the fuel pump and the stator. Try priming the engine by pouring a little gas in the throttle body. If it fires its probably the pump. The fact that you had physical damage in your distributor makes me think the cam position sensor, or stator, or sync signal generator (lots of names) is probably what's causing the problem though as it is inside the distributor.

mctod22

Thanks I'll try that next

Turbo X_J

With the ignition ON do you get 12v to the coil?

cruiser54

Just an FYI:

The stator/sync generator will not keep a Renix from running like it will on an HO. If the stator fails, the system will "batch-fire" the injectors instead of firing them sequentially with the firing order. A faulty stator will not be noticed by most people as a driveability issue. I've found bad stators by observing them with my DRB on an engine that ran pretty darn good. Had I not hooked up the DRB, I wouldn't have suspected a faulty stator.

mctod22

I replaced the cam sensor I had the part under warranty when I replaced distributor in march. Still no luck on firing I also replaced the coil resistor with no luck either. I only checked the conector to the ignition module with a test light. It had power not sure of voltage and it was only on one of the prongs was hot I think that is right correct me if I'm wrong

cruiser54

Unplug the CPS. With your meter set on AC volts, put a probe on each of the CPS wires in the connector. Have someone crank the engine over while you read the meter. You need 500 millivolts AC or .5 volts AC depending on which scale you use. Any less than 350mv and you can have a no-start. This is a much more reliable test than the ohms test for a CPS.

mctod22

I'll try that if that is the problem what is the next step

Slick761

Keep forgetting that.

cruiser54

Let us know whart you get from that. I do better in real time than in the future.