Having tackled the valve cover gaskets earlier this year, I found that the car was running differently. No longer was the idle as clean as it was and in fact if feels as if the car has lost power. I decided to look into it.
I read about possible causes on a rough idle on stangnet.com. I basically went through the checklist and have done the following:
- Cleaned salt and pepper connections at the rear of the intake plenum
- checked air filter
- checked voltage from alternator
- MAF sensor was previously cleaned
- replaced IAC valve
Still, the car didn’t run as it should so I decided to pull the codes from the car’s computer. I believe I retreived a 22 code which would indicate something’s amiss on the Barometric Air Pressure sensor. So I replaced it and without driving the car, it looks like it ran better but when I pullled the codes again, the 22 reappears. Not sure if it is a stored code or simply a problem with that circuit.
Since I was already working on the car, I decided to remove the throttle body and clean it since it does have advanced mileage. Ended it having quite a bit of carbon buildup on the throttle body and especially in the EGR spacer. I cleaned these items and have replaced the gaskets.
Still to do: I have to check the output on the TPS to make sure it’s within acceptable range and test drive the car. More to come.