00cherok

Seems to be getting worse. Runs fine down the road. Having issues while plowing drives. At times it seems like someone turned the ignition off. Today it happened 3 times in one drive. Drove to the next and plowed it out, worked fine. When it dies, usually it takes a little bit to get it started. Sometimes it starts right up, other times I crank, turn off the ign, crank, turn..... etc.

2nd to last drive when it killed, when restarting it acted like it was flooded. Firing, but took awhile to get it started. After it started, went to back up and died right away. Sounded like it was flooded again. Also noticed while starting, the rpm needle was jumping all over the place. Once it started the check engine light came on and stayed on. Ran fine since at my last drive. Today was the first time it acted this bad, seems to be getting worse. Have a feeling one of these times it won't restart.

A side note, when I start the engine whether it's cold or still warm after running into a store, I have to cycle the fuel pump twice b4 it starts. Not sure if the 2 are connected... Or, if the pump is just getting weak......
Thoughts?

EvilJeepxj

The tps controls the IAC , it also gives it enough throttle to start, when the tps gets worn out you can usually start it by touching the throttle a hair at a time as you crank it and it'll stay running once warm, other bad tps symptoms include extremely low idle and jumpy rpm guage could be a bad connection to the cps as well. If your also getting shuddering at idle these are notorious for header cracks causing rich condition because of a colder o2 sensor reading.

Dave51

Sounds like a bad CKS exhibiting "thermal sensitivity". Check that you're getting a 5 volt signal during a problem period.

Dave51

Or maybe it would be more appropriate to say "Check that you're NOT getting a 5 volt signal during a problem period".

Hokieman

Since it happens when you have impacts during plowing, it may be broken solder joints in the auto shutdown (ASD) relay under the hood. A known issue with the original relays that can be infuriating to find. You can check the relay when the vehicle won't start, or just replace it for $28 from the dealership.

00cherok

Were is it located, makes sense. Not in the fuse box? I replaced the electric fan relay there since it was shot, including the fan. I'm sure the sensors , relays are all original. I may start replacing sensors on the throttle body too.

Thanks for the responses, keep them coming. I think someone mention on FB CPS? But wouldn't the CPS issue happen going down the road too? Been trying to do some research. Only posted my issue on this forum.....

I don't mess around. I like replacing with new parts since it has 207k miles....

00cherok

I found it. I think I'll replace the TPS too. When plowing the engine bay gets hot. Engine temp doesn't run hot. But there is so much heat the water bubbles on the hood from the snow steams when plowing...

EeeSkwa

If it keeps happening, I would check out the Crankshaft Position Sensor, as well. Can be the cause of symptoms you have.

fb97xj1

The hood gets toasty with the 4.0L, even when they arent running hot. Thats just the way they are. Not starting is, many times, a faulty crank sensor. It sits in the hottest spot in the engine bay, right next to the exhaust manifold. If your 00 has precats, that adds even more heat, and cooks the crank sensor further. The magnet eventually fails. IF you do need a new crank sensor, buy Mopar. Aftermarkets have a crappy reputation for being DOA. The magnets in them are garbage.

Inspect the wiring itself as well when testing the sensor. This includes the connector, for any corrosion or pins that may have backed themselves out. I dont see it often, but it has happened.

00cherok

Thanks. That sensor comes out, it's getting replaced....

00cherok

Thanks. That sensor comes out, it's getting replaced....

00cherok

I'm dreading that task, but I'm 1 step closer to doing it. Where does the CPS plug in on a '00?

Replaced the ASD, didn't solve the issue. Quit on me while plowing the 1st drive. Check engine never went out. Worked fine until I tried running down the drive while pushing the berm back. It's a long drive. I was heavier on the go pedal while the blade was in the berm. When I let off the go pedal at the base of the drive, it quit. Tried starting it and it resisted. Acted like it was flooded again. Gave it gas while cranking still had a tough time starting. Ran rough, sputtering, sounded like it may have backfired thru the throttle body a couple times. Had to keep the rpms up around 3k to keep it running. Eventually smoothed out, put it in reverse and died instantly. Saw black in the snow from the tailpipe. Got it started and running good again and left the drive. When I let off the gas at the end of the drive, it quit. Didn't want to start. Let it sit for a couple minutes and it cranked right up. Smelled nasty too. Ran fine going home and at stop signs. Back drug by my garage and pushed the snow away, ran fine.

I had to order the TPS which will be here Tues....

More thoughts?
Thanks

EvilJeepxj

The tps wears out and it tends to fail most in the wet snow and rain first, but also your working that motor harder then it ever normally would , I would remove the thermostat if your finding its having trouble keeping cooler then boiling more often then not, 2000 is prone to head cracks 0331 heads, you can lessen this risk by removing the thermostat because it lowers the pressure at which the water will reach because it lowers the temp at which the water stays at, 150-190 instead of 180-220

00cherok

It runs at 210 just like in summer so it isn't overheating. I replaced the whole cooling system except heater core this fall.... I read about the 331 heads after I bought it. I've gone about 3k miles since purchase and it doesnt seem to be eating coolant... Hope the TPS works...

00cherok

I was pushing 16" of heavy snow a couple weeks ago and it ran fine. This is a new development...