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Ignition timing help

Featured Replies

20 hours ago, Espey16 said:

Seems to be running a little better now, still wont idle when it's cold. 

 

Clean the IAC if you are sure the CTS and all connections are good.

  • 3 weeks later...
  • Author

Is there a gasket that needs to be replaced or anything? I haven't pulled it off yet. My plan is to get to it tonight after work.

  • 6 months later...
  • Author

Figured it out. 5+ years of owning this car and it not idling while it's cold, you guys would want to punch me in the head. MAF was bad. I had a code, and I cleaned it and the housing, no dice. Bought a reman from rockauto and now it idles cold. Idles finds rough though.

  • Author

I was thinking the timing was off because I timed it with a  bad MAF, but I re timed it and adjusted the idle and its still running a little rough. Timing shakes around 20* btdc and the idle will bounce between 1k and almost dead. Im trying to get it to idle around the 700 mark.

Do an ecu reset and let it work out the idle setting. No use you trying to sort it mechanically while the ecu is trying to do the same. 

Cheers 

Bennie

  • 2 months later...
  • Author

Still idles rough, and dies at times. Sometimes the idle bounces between 1000 and 1500 rpms. I cleared the codes and there was no difference. I know I need to calibrate my tps, I just can't find the proper size feeler gauges.

Tried replacing the coolant temp sensor? 

This could be a bit left field, check the cam belt timing marks are still aligned correctly. 

And check for vacuum leaks. 

Cheers 

Bennie

  • Author

Its brand new, and I just re tensioned the belts a couple weeks ago. Im fairly certain its the tps thats the problem now. When I replaced it I tried to line it up the best I could with the marks on the old one. It wasn't perfect but it runs.

  • Author

the cts was one of the first things I replaced, $70 later and I have a lifetime warranty on it now.

is it better IMMEDIATELY after a battery disconnect reset? if so, that could point to a bad sensor. If not, the problem could be something physical; valve problem or injector problem or ????

the ECU ignores sensor readings for a coupla drive cycles after a reset, it just reverts to using a factory baseline ROM with nominal values.

 

in theory - lol

Going on twelve months here....

Crude I know, if you can physically hold throttle by hand, against its throttle stop and still have its idle crazy it won't be the throttle plate adjustment.

It almost needs to be fast idle control circuit or a device within it

Or

EGR make a block off plate for diagnostic needs. I had wicked idle and performance issues until I blocked off then replaced MPFi EGR

Or brake vacuum booster is another source for a fast idle air control ..comes under vacuum leak suggestion 

Get some caps to blank off all possible vacuum leaks to inlet manifold only while not driving it of course

Vacuum leaks don't really often? cause big idle rev differences with smooth idle, more rough idle

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