Hello fellow XJ owners. I have a 1993 cherokee sport 4.0L 159K. I though I had the cut out problem fixed with a new CPS sensor. but the Jeep dies when I have the blower turning. I recently replaced the fan motor and the fan blower resistor.

Parts I have replace
new exhaust and cat
CPS sensor
TPS Sensor
IAC valve
All new relays ASD,FUEL pump,A/C,Starter in the relay box.
Stator/pickup coil
New cap rotor 12K ago
Fuel filter
new fan motor
new fan resistor

I sometimes have spark and sometimes not when it dies. After it cools off it will fire right back up
fuel pressure reads 29 and 37 when the fuel pressure regulator vacume is pulled. ( read it should be 31 and 39PSI)

But I can consistantly get it to fail when I have the blower motor turned on. I tested the new CPS and it tests fine. thinking it could be a new faulty CPS.

the funny thing happened when I replace the new ballast resistor it started smoking and got hot. I put the old back in till I can ask autozone what they sold me.

After all is this my idle is a little lower as well with the engine goes into drive.

Can a code reader pull code off of a 1993 sport. I think it's a obd I type also where is it? the CEL light does not come on.

Thanks in advance

 

Is it stalling at a higher temp than 220? or right at operating, if hotter it could be vapor lock. If not than try the fuel pressure regulator, I have had this problem before and it was a bad regulator.

 

I usually run when operating l little hair over 210 on the gauge on the dash. I am borrowing a temp gun and see what the temps on the engine.

 

Have you checked the charging system and the battery? The blower may be pulling too much juice and causing the engine to die because there is not enough voltage to keep the ignition alive.

 

I was wondering if I should look the battery gauge varies from day to day and temp. Sometime I read 14 and sometime it drops to 12 or 13 if it's hot temp. Might pull the alt and get it checkout. I did change the negitive battery cable as well. Might have to change the positive side as well.

 

Has anyone heard if the BWD brand of CKP/CPS sensor can be out of spec?? I did not use the stealership to purchase.

Fred

 

You can try that, but I still have money on fuel pressure regulator.

 

BWD has been around for years, you should be ok with that brand.

 

Check your hall effect pickup in the dis ,might be a possiability.

 

Don't pull the alternator, it's controlled by the PCM, the laternator puts out 13+ volts, then it's fine.
Try this, while engine is still cold.
Disconnect the temperature sensor at the goose neck.
See if anything happens after 30 seconds.
The electric fan should come on, and engine should not die down.

 

I will try that temp sensor at the goose neck.

 

I took several recommendations and I think I have 2 problems. The new fan motor and fan motor resistor. I causing something electric with either too much surrent draw or something.

Also I replaced the Fuel pressure regulator the fuel PSI are back up to 31 and 40. I also replaced the temp sensor on the themostat housing. I did the test when you remove the sensor harnes and the elecric fan come on. So the new sensor is working. I made the mistake of replacing the coolant gauge sensor and it reads warmer than the laser temp sensor guage I have.

When she dies after getting warm I get no spark and the fuel pressure spikes to 50 PSI but then dies out. The fuel pump when running sounds fine. I change the asd relay and the fuel pump relay.

Do you think the new CPS from BWD is the problem. When it got hot the 1st time I quickly checked the CPS sensor and I was reading the low resistance on the b and c terminals. After it cools down it reads open but still no spark?

anyone else have any idea's..

Thanks

Fred

 

Sounds like it could be a cam sensor problem.

 

x2 my money is on the cam sensor. But also could possibly be a faulty cps. I know I will get bashed for this but...I always buy my sensors from the dealership....
Good luck!

 

Hi All just wanted to post the fix to my XJ engine just dying It ended up the BWD part I got. The pins on the CKP where to small for the connector and making intermitant connections. I got a new Delphi CKP from Napa and it has the flared ends to make better contact with the engine. Threw alot of parts but the 1st part I replaced was the bad part.

Fred