Fast Idle (1 Viewer)

Nov 4, 2007
The ECT is likely high, due to dirty radiator fins. Can be other issues also.

But if your running lean, like a vacuum leak. This will have engine running hot. It also may be due to vacuum leak.

I can't be of help much with scangauge. But I'd assume you just scroll through available data points. TLFT STFT may be how listed. I use a blue driver. Which logs and I can then look back at moment by moment over as much time as I've logged.

We're just interested if fuel trims showing anything strange. Reads between + or -5 % while throttle steady is normal. Getting over -+15% is get bad. Even -7 STFT (short term fuel trim) is indication of lean fuel mixture. LTFT would then or should then be positive about 7%. As it (LT FT) show the new baseline ECU has set to correct short term (ST).

You need to read tech stream for codes pending. Assuming your "CEL" is working, present should have CEL on, pending would not have CEL on. Easy to check if working, as it should be on with key on, off while engine running. Find a parts store and see if they can read pending codes.
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Oct 18, 2015
Northlake, Texas
possible vacuum leak? all those hoses going to the air box see if any have any cracks, splits, etc. possibly got a hairline in one. check the maf connector to see if pins are good and straight and reconnect. also might need to let it idle for a while for the computer to re learn idle. mine took about 15-20 mins before it settled down after cleaning both those and battery disconnected for duration. Some freebies to try..
May 6, 2018
Had to leave town shortly after noon to head home so wasn’t able to investigate any further. The CEL does work and isn’t on. Scanguage shows no codes and also has ability to show pending codes, but not picking any up.

Will have to take another look for vacuum leak. Initial check of hoses all looked good and connected.

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