I searched a little but didnt find what I needed so here goes.Has anybody had the code p0128 and no other code and the car stumble for a sec and then run fine?This is driving me nuts the coolent isnt low the temp gage goes up to temp everything seems fine.I dont understand where the stumble is coming from because it is fine after and runs just as smooth as can be.Just wondering if anyone else has the same problem. Thanks for your time.

When is the last time the thermostat was changed? Another possibility is the ECT is going bad. Have it tested.

Thermostat I dont know but i dont think thats it because the gage reads fine and is at 200 normally.The ect I can see as a posibality and will change it out on tuesday after work.I just dont understand where the stumble is coming from.It just stumbls for a sec then it fine.Would the ect cause it to stumble?I have worked on cars with this motor and never had this problem before.Thanks for your time.Dave

Sensor problems are often caused by faulty wiring or loose or corroded connections rather than the failure of the sensor itself.

Thanks again Dan you are always on here.Will the ect cause a stumble?If it could I am going to ghange it due to only being 12 bucks.I just cant see this causing a stumble.

The PCM needs to know what temp the engine is, and that'* where it comes from. So conflicting signals will cause problems. I'm sorry I don't have a write up on how to change one, but it'* very easy.

Drain your coolant a little.
The ECT is under the thermostat housing.

Remove the old one and put in the new one. Connect the wires, refill the coolant, your done.

Thanks Dan.Where do you get all your info?Do you have alldata?I like all of your tech writeups.Thanks for all of your help.Dave

Lot of it'* from my head. Been working on cars for about 35 years. I also have a FSM sitting right next to me so I can pick it up to answer questions and get diagrams when needed.

I got this code after i did a flush filll and changeover from Dex to Green stuff.

My buddies get the same code this time of year (cold) and they have also changed over to the green coolant.

Is it related? I had never gotten this code until the cold weather that proceeded the dex to green coolant change over (and I've never replaced my thermostat).

Just curious.

You can get this if your engine doesn't heat up fast enough. I think it'* 2000+ that can have this problem.