Benwallage9

Hey folks, new member to this forum but have used advice found on here quite a bit and it has been a real life saver.

I am currently trying to figure out a rough start issue. When it is cold the jeep starts fine (1996 4.0l) when it is warmer it has a real rough sputtering start, if I rev the engine a couple of time while it's sputtering it runs feel after, if I don't rev the engine it will die.

After reading a didn't post on here I am beginning to wonder it it is the coolant temp switch. I recently got a champion radiator that came with a thermostat switch. The only place I thought it would fit is in the thermostat housing for the cts. However, I now only have the champion ts connected to the fans.

Does anyone think that this could be the issue? If so what would be the fix? Replace the champ ts with stock cts and install the ts somewhere else? But how and where?

After watching another video a guy mounted a different ts switch in a bung pre installed on the radiator however this bung is much to big for the ts champion provides.

Any advice is much appreciated. Thanks for taking the time to read this.

aka"dude"

intake air temp?

MWMahoneyJr

Maybe air intake temp - mine was a rough start when warm, then rough running when warm. Cold start was fine.

Check my build thread, in post #1 I test the sensor.

Other people might mention an issue with heat soak - once the engine is warm, hot air coming up from the exhaust vaporizes the fuel in your fuel rail - causing a hard start. I think people install a heat shield around injector #3. Read up on "heat soak."

Benwallage9

I think I got that fixed after talking with a guy over at champion I ended up putting in a tee to allow both thermo switch and coolant temp sensor. Ended up splicing the grey wire and grounding it and the thermo sensor is supposed to be grounded by block. Rough start has gone away.