Weird Cold Starting, WTF

[Thomas.hummelt]

I own a Jeep Grand Cherokee, 1994 4L Inline 6. It has serious issues starting when its -10 or lower, even when its plugged in. However, anything above -1 it has no problems. The engine cranks and cranks until i put pressure on the gas, and the only way i can get it to start when its cold is to pump the gas, and seeing as its fuel injected, im confused on why i need to pump the gas. I changed the air temperature sensor in the engine and that didnt really help. Any ideas?

-I can hear the fuel pump running when i start
-Starts without fail 100% of the time when its warm out
-Even when plugged in it still has difficulties anything colder then -10
- Next to new spark Plugs, distributor cap
- New fuel filter
- Brand New tranny
- Everything else works fine.

[morerpmfred]

Fuel filter. Super fine sludge in there and a tank of gas with water from some time ago. When warm , fuel flows through but when cold, frozen sludge does not let fuel through. Used to be kinda common but with good fuel filters at the pumps and alcohol in the fuel it went away.

[apeman]

Cps. The Boone of the 4.0l.

[Immortal]

Cps. The Boone of the 4.0l.

 Bwahahahahahahahahaha!!!!!!!!

[Thomas.hummelt]

Well i just put a new fuel filter in, and i checked the fuel rail, and there is gas getting to the pistons, there is just no ignition, i checked the sparkplugs there almost new, the Dcap is brand new... i just cant FIGURE THIS OUT AND ITS KILLING ME

[Immortal]

Crank position sensor.

[cLAY]

X 5 for CPS.

[Thomas.hummelt]

Yeap ive been doing some research and that sounds like a problem, damn those things arent cheap either, but as is the life of a jeep owner. However would the CPS affect the idle? it seems that i can get it to start but it will die after a second of running even if its "warm" If its been "hot" for a while it has no problem starting back up and it wont die but if its been sitting for about 6 hours it will sometimes start up but die.

[Immortal]

The cps tells the system when to spark. It's a sensor, they do weird things at different temps.