I am having some really strange issues with the driveability of the vehicle.
2.2 Ecotec with 4 Speed Automatic with 109k miles
The check engine light is on, and I pulled code P0327 (Knock Sensor Low input voltage) and P0507 (Idle control system RPM higher than expected)
I changed the knock sensor out, reset the codes, CEL comes back on with the same codes. Cleaned the IAC valve and throttle body, that didn't do anything either. Checked the ECU plugs for corrosion, didn't find any, hit both the plug and the pins with some electronics cleaner, cleared the codes, same code popped right back up. Now recently it's been getting better, then worse with how it runs.
Idles at stock RPMs but a bit rough, but also sometimes but less often idles around 900. If I put it into neutral or park, it will shoot up a little over 1k RPMs, then fall back down standard idle speeds, or 900RPMs.
Now recently, the speedo needle has been randomly dropping while keeping a constant speed, and today it did it the worst I have seen, it dropped all the way to 0 MPH while cruising at around 20 through a parking lot, and I noticed when this happens, the transmission will not shift until the needle shoots back up to where it;s supposed to be. Also when this happens, the engine starts hesitating really badly in random bursts.
Also the Trac Off light keeps coming on, and going off multiple times in a short drive. Although when off, the traction control works as intended.
This car HAS in the past been totaled, and rebuilt, and inspected and approved for a Rebuilt title. Apparently from the previous owner, they said the whole front clip of the car was replaced.
It wouldn't surprise me if the ECU might have been damaged in the crash that totaled it, and since I found on google that 3rd Gen J Body ECU failure is quite common. But I am reluctant to replace it, since it requires Tech2 programming. Granted, I have found a website that sells known used, but working ECUs, and will program it for my VIN before shipping, for a total of $80.
But I am also concerned that it may be the engine wiring harness, since sometimes the car runs perfectly, and other times it runs like complete crap. It's never failed to start, and always starts on the first crank.
Also I went ahead and changed my screen name. Sorry for the double post. Didn't realize it was going to use my real name. lol
and it just threw a hard "Running too lean" code
