[jeepunlimited]

hey guys, wondering if anyone could tell me what the signs of a bad cam sensor would be in my 93 ZJ. I have long cranking times when the engine is cold and im wondering if it has anything to do with the cam sensor. (crank sensor has been replaced)

if anyone can let me know the signs of a bad cam sensor, it would be greatly appriciated

[-Joe-]

usually a check engine code #54

[Mooman]

I don't know if it is or will be your cam sensor, but my brother and I just went through this. If it comes down to buying one, don't go in and ask for a cam sensor. They will look at you like your crazy. It's called a hall effect sensor.

[Wheelin98TJ]

Its a spark related sensor, so if your longer crank times are due to a lack of spark problem, its a possible cause.

The more likely problem you're having is with the anti-drainback valve. This valve is responsible for keeping the fuel lines primed. When it goes bad, the fuel rail will lose fuel pressure if the vehicle sits long enough.

It starts fine when its warm?

[gpJeep]

Cam sensor problem look like an old worn out engine ..

like low feul pressure related problems

codes are not always thrown by the obdii

the engine will stall intermintenly at times while driving

a new sensor is about 50 smakers

[jeepunlimited]

Originally Posted by Wheelin98TJ

Its a spark related sensor, so if your longer crank times are due to a lack of spark problem, its a possible cause.

The more likely problem you're having is with the anti-drainback valve. This valve is responsible for keeping the fuel lines primed. When it goes bad, the fuel rail will lose fuel pressure if the vehicle sits long enough.

It starts fine when its warm?

yep fires up mint when warm, is this anti drain back valve hard to replace ?? i just did the fuel pump in my jeep soo low fuel pressure isnt the problem but it could be a worn out 4.0L ...it does have 380 k on it

[BLACKzj52]

Originally Posted by jeepunlimited

yep fires up mint when warm, is this anti drain back valve hard to replace ?? i just did the fuel pump in my jeep soo low fuel pressure isnt the problem but it could be a worn out 4.0L ...it does have 380 k on it

well if im correct u have atleast 210k + miles on your jeep...
so it could just be worn down..

[Wheelin98TJ]

I'm not sure on a 93 ZJ, but on a TJ, the anti-drainback valve is part of the fuel pump assembly in the fuel tank.

[gpJeep]

then agian it could just be a worn out cam shaft
and all the lifters
and other thingys

[rm2001wj]

The IAC (Idle Air Control) solenoid might not be resetting when the engine is cold. That could not let enough air in for good combustion on cold start up. Try a cold start with the accelerator pedal pressed down a little to see if that helps.

[sastanley]

Do you hear the fuel pump prime when you turn the ignition to "ON" but don't try to start it? I had the PCM/ECM/Computer act up which didn't fire the pump. 30-45 secs of cranking would get it to start. I ended up getting a new computer from Rock Auto.

[nashmd454]

Originally Posted by BLACKzj52

well if im correct u have atleast 210k + miles on your jeep...
so it could just be worn down..

yeah and you have 17 on yours...

[Dagda]

The cam shaft sensor will cause it to stall while driving. Sometimes it will start right back up. Crankshaft causes it to not start especially in damp weather; fog, rain high humidity. The check valve will cause delayed starting, but if you turn the key to the on position for a few seconds, then to start, it should fire right up.

[brandon96zj]

i have a 96 zj and it stalls in cold damp weather any ideas but it only does it when warm and while stopping?