Dodge 2.2 TBI code 22

[redline]

I have had a cold start problem recently with a 1989 Dodge Omni 2.2 TBI. It has 125K on the clock. I pulled a stored code 22 (Coolant temp sensor out of range. The CE light was not illuminated it was stored. I replaced the plugs and Coolant Temp sensor. Now I have a CE light illuminated and still get a code 22. It fires right up now but runs worse even when warmed up and has a fluctuating up and down idle. What do you think?

[OptiCon]

You did clear the code since you fixed the sensor correct? Pull the battery for 30 seconds?

[redline]

You did clear the code since you fixed the sensor correct? Pull the battery for 30 seconds?

You know I'm not fimilar with OBD1 and figuered it cleared itself. So if I clear it I should only get a code 12, recent disconnect of battery?

[redline]

Ok, I cleared the codes. Started it up and it runs fine. I took it for a drive to warm it up. I was sitting in my parking spot when the fan kicked on for the first time. As soon as the fan came on so did the CE Light with a code 22. What do you think? I am in the process of OHM both (old and new) sensor at room temp. I will post results.

Edit: At 70 degrees both snsors are around 10,000 to 11,000 Ohms. And both's resistance falls when you warm them up in your hand.

[OptiCon]

Could there be a short in the ground to the sensor? Thus lowering the signal voltage to the PCM out of range?

[redline]

Could there be a short in the ground to the sensor? Thus lowering the signal voltage to the PCM out of range?

Man I don't even know. I cleaned up the old sensor and reinstalled it. Cleared the codes and it ran fine. Went for a 20 minute drive and still no CE light. So I park and shut off the car and then pull codes to make sure none are still stored and I get a 23. Intake Air Temp Sensor may be out of range. WTF! car runs good and gets great gas mileage.

[OptiCon]

A different sensor now? I would venture to guess the problem has to do with the PCM and not the sensors. It stinks of an inconsistent ground connection. Find as many grounding points as you can that have to do with the PCM and clean them up.

One easy thing you can do is pull the big plug that goes into the PCM itself and see if it's all grimy. a little clean-up and some dielectric grease should ensure you never have another problem there.

Good luck.

[redline]

A different sensor now? I would venture to guess the problem has to do with the PCM and not the sensors. It stinks of an inconsistent ground connection. Find as many grounding points as you can that have to do with the PCM and clean them up.

One easy thing you can do is pull the big plug that goes into the PCM itself and see if it's all grimy. a little clean-up and some dielectric grease should ensure you never have another problem there.

Good luck.

I'll look into it, the car is running fine today with no codes and still gets around 30MPG. I am going to buy it reguardless!