I'd like some help with the EGR pls
I got a Motor Control System Fiailure light and it points to the EGR valve. Took the EGR out today.
The spring, the pin and everything else in there was stuck or hardly moving. So I cleaned everything with WD40 and some paint thinner (works well). The pin is moving easily, the spring valve is also moving ok.
I put it back in, bolt on everything tightly, start the car and immediately get a very rough idle (revs jumping from 400 to 800 rpms).
So while the car is still running, I disconnect the EGR electrical connector and the idle suddenly becomes fine. Connect the connector and the idle is rough again.
So how is it that when the EGR is definitely not working properly, I only get the MCSF light and everything else is fine (mpg & acceleration are both normal) and when it's supposed to be fixed, the idle becomes rough?
Can it be so that maybe the EGR has been stuck for so long, that the car adapted to the not-working-egr mode, so that when EGR does work the ECU has trouble figuring out what just happened?
Maybe an ECU reset would help? How do I do that? Read something about disconnecting the battery for an hour, start the car and not touch throttle for 15 mins, turn it off for 10 mins, after that go for a drive... Is that the one?
P.S. I didn't try and drive with rought idle, but just revving up seemed fine. I am now driving with the EGR connector disconnected.