RPM fluctuation at idle
Quote from bdhulderman on September 19, 2019, 10:53 amHere are the instructions:
Yeah, it says it just includes the temp sensor update, but it worked for me.
I will give it a try. Not much to lose. Thank you.
Quote from tony-muscle on September 19, 2019, 12:26 pmQuote from bdhulderman on September 19, 2019, 10:53 amHere are the instructions:
Yeah, it says it just includes the temp sensor update, but it worked for me.
I will give it a try. Not much to lose. Thank you.
I uploaded the latest version of the software and made no difference on the fluctuation issue. Anyone has other ideas on how to diagnose what's going on?
The 198i software has a lot more updates than the coolant temp adjustment.
I would like to see a 30 second idle log at operating temp. Must use Dropbox to share. Add log to your Dropbox account, create a link and paste on next post.
Austin. Thank you. I am sharing the link to dropbox with you via email.
For anyone interested in looking at the files they are uploaded here with the file type changed to PDF. You can download them and then change the file type to CSV.
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Quote from Austin DeHaas on September 22, 2019, 3:48 pmThe 198i software has a lot more updates than the coolant temp adjustment.
I would like to see a 30 second idle log at operating temp. Must use Dropbox to share. Add log to your Dropbox account, create a link and paste on next post.
Austin, were you able to look over the files that I sent you? Any ideas?
Today I drove around for a while and then checked for vacuum leaks by spraying carb cleaner around the base and around the manifold. Idle did not change which may be a good indication that there are no vacuum leaks. This idle fluctuation is kind of annoying because I can't idle the car in gear. It starts jerking until I tap the gas. Does anyone have ideas about this idle fluctuation? Is it an adjustment? Is it RF interference? Maybe my distributor or CDI box?
Austin, were you able to look at the files? Thank you.
I had a similar issue with a leaking header gasket which was only about 2" beyond the O2 sensor. Make sure your exhaust is not leaking. Just a thought...
Quote from javelin_72 on September 30, 2019, 10:21 amI had a similar issue with a leaking header gasket which was only about 2" beyond the O2 sensor. Make sure your exhaust is not leaking. Just a thought...
Thanks. Today I checked under there and I had a couple of small leaks after the O2 sensor, but not before. When you mean "beyond", do you mean between the sensor and engine, or sensor and exhaust tip?
Exhaust leaks just past sensor can cause issues also.
Quote from Austin DeHaas on October 1, 2019, 9:36 pmExhaust leaks just past sensor can cause issues also.
I saw three small leaks within couple inches of the sensor. Luckily they are in a location that I can get to so I will weld those tomorrow night. I also have exhaust cut outs that don't seal perfectly. Can someone explain why a leak past the sensor can create issues? Are we talking about tiny leaks affecting or only large leaks?