High Idle problem!

[flynaked]

Just finished my conversion and everything is great, running real well just having idle issues. When I first start the truck it idles at 1k, stays there just fine, but as soon as I drive it and let off the gas it climbs and holds 2k. Everything I can think of goes as follows, vacuum leak, but it would be a constant 2k idle and never hold 1k if that were the problem I'm guessing. Possibly throttle position sensor. Mass airflow, even though it didn't throw any codes it is the mass off of my 4.3L and I had the same problem sometimes with the v6, just not an all the time deal, so I guess that is the issue somehow, that is the only v6 part left in the conversion, but it still could be something with the tune maybe. It has a nelson tuned pcm. At first we thought it was tuned with a big cam idle because it was holding 2k then dropping, now it is a constant issue, every time I put it in neutral. Any thoughts? Thanks

[93blackbeast]

This happed on my car when it had the LS1 in it. What I had was a faulty TPS sensor. To figure this out, I would go pull the plug from the TPS as it was running and then plug it back in and the RPMs would drop back down to the 1000 mark. I changed the sensor out and didn't have anymore problems after that.

It may not be the cause of your issue, but its just something to look at.

Cody B.

[flynaked]

Thanks, that was another thing I was wondering about but didn't know if it could be it, but now that you mention it, I pulled the tps from a 76mm 4.3L throttle body, that may be an issue but I think they are the same sensor but still that one may be bad, thanks

[GasGuzzler]

Thanks, that was another thing I was wondering about but didn't know if it could be it, but now that you mention it, I pulled the tps from a 76mm 4.3L throttle body, that may be an issue but I think they are the same sensor but still that one may be bad, thanks

Why do you keep posting a DOT?

OIC, you put a "." in the title of your reply...

[flynaked]

Oops, never looked at it, thought you had to put a title so I always just hit a dot to be quick, but really, it doesn't matter..