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In the spirit of sharing, as we all know sharing experiences can help others etc....
Had the girlfriend pop over to work saying the EML is flashing and it seems to be stuttering.
I said a flashing EML indicates a misfire, so I'll plug it in to the box of tricks and see whats a foot.
Plugged in to the trusty All Comms and read the codes - now we have a VANOS issue and Control Bank 1 fault which I know about and will get round too, yes, there were misfire codes for cylinders 4 & 8, but they cleared down OK and didn't return after a good blat about for 10 minutes......but a curious fault was shown stating thus:
Electronic Throttle Monitoring/Self Test - Control Gain Adaption Error
This one won't clear, so it looks like there is an issue there.....
The Throttle body uses a small stepper motor to open and close the butterfly valve on the command from the ECU. To monitor the butterfly position there are two potentiometers, Pot 1 and Pot 2. One is the primary and the other is used as a plausibility check for the first one - the ECU will take the MAF data and use the value of either pot that would closely resemble what the MAF is telling it, if neither are near what it expects it shuts the injection system down and you get Engine Failsafe mode..
The car idles with a slight lumpy-ness which I am attributing to the VANOS issue, but also the idle speed seems a little low, and on very few occasions (but it has happened) once you start her up, she idle then drop out, and you have to start her up again - this has happened 3-4 times in the last 7 months or so...but is curious nonetheless.
She drives well - aside from the VANOS issue and the VANOS rattle she has at the moment, but she'll accelerate away well, no popping or farting from misfires, so I think that is spurious....but this fault code won't clear so something is a miss.
I have no resolution at the moment, but I have told her to keep an eye on it and report any further strange behaviour, but it *may* mean a replacement Throttle Body.
The only bugger is the replacement body would need to be set up to the ECU to learn the replacement body pot settings and this can only be done on Testbook - not sure if Faultmate can do such....
Anyhow, that's another bridge if/when the throttle body gives up.
Any news I will update, but in the mean time if anyone has any opinions, thoughts, knowledge or experience - please do share....
Had the girlfriend pop over to work saying the EML is flashing and it seems to be stuttering.
I said a flashing EML indicates a misfire, so I'll plug it in to the box of tricks and see whats a foot.
Plugged in to the trusty All Comms and read the codes - now we have a VANOS issue and Control Bank 1 fault which I know about and will get round too, yes, there were misfire codes for cylinders 4 & 8, but they cleared down OK and didn't return after a good blat about for 10 minutes......but a curious fault was shown stating thus:
Electronic Throttle Monitoring/Self Test - Control Gain Adaption Error
This one won't clear, so it looks like there is an issue there.....
The Throttle body uses a small stepper motor to open and close the butterfly valve on the command from the ECU. To monitor the butterfly position there are two potentiometers, Pot 1 and Pot 2. One is the primary and the other is used as a plausibility check for the first one - the ECU will take the MAF data and use the value of either pot that would closely resemble what the MAF is telling it, if neither are near what it expects it shuts the injection system down and you get Engine Failsafe mode..
The car idles with a slight lumpy-ness which I am attributing to the VANOS issue, but also the idle speed seems a little low, and on very few occasions (but it has happened) once you start her up, she idle then drop out, and you have to start her up again - this has happened 3-4 times in the last 7 months or so...but is curious nonetheless.
She drives well - aside from the VANOS issue and the VANOS rattle she has at the moment, but she'll accelerate away well, no popping or farting from misfires, so I think that is spurious....but this fault code won't clear so something is a miss.
I have no resolution at the moment, but I have told her to keep an eye on it and report any further strange behaviour, but it *may* mean a replacement Throttle Body.
The only bugger is the replacement body would need to be set up to the ECU to learn the replacement body pot settings and this can only be done on Testbook - not sure if Faultmate can do such....
Anyhow, that's another bridge if/when the throttle body gives up.
Any news I will update, but in the mean time if anyone has any opinions, thoughts, knowledge or experience - please do share....
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