3800 Idle Problem!!!!!! HELP PLEASE

[98 TGP TOY]

I was getting off the highway today when I noticed that my idle would not go below 2,000. When cruising about 40mph it will keep accelerating my car. When in park my car will idle at 2,000 and then creep its way up. My only thought is a bad TPS or something with the TB plate. But I dont know what it is. So any help is greatly appreciated. Thank you.

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[imported_Ron Vogel]

I had someone over that had a lazy IAC. Never really figured out why, we even switched it out for another, and it was still kind of there. It seemed to help cycling the ac on/off. It raises the idle when you turn on the ac, it helped unstick it.

 

[Mike K]

Scan the car and check what your long term fuel trim and your 02 readings are. I'd be willing to bet it's a rather large vacuum leak or something stuck under the throttle.

 

[98 TGP TOY]

Well, I let the car sit for a while, and its gone. How annoying... So we will see if it pops up again. Im pretty sure its not a vacuum leak, because everytime I get a vacuum leak my car dies or idles rough. This was idling fine just at a high rpm. Ill try to take scans next time it happens, but I didnt have it on me this time. Well thanx for the suggestions, if it happens again Ill check it out.

 

[98 TGP TOY]

Hey Ron, just seeing if you got my PM about the TB.

I wonder if the TB plate was causing this problem. If i open the throttle and let go it makes two sounds. It sounds like its swinging or bouncing off. There is no movement from the cable assembly that would make the second sound. So I wonder if the plate is loose or soemthing.

Also, I have an extra 97' TB. What would I have to do to make it work on my 98'. I was thinking they were the same, and didnt chang until 99+. Also, can I take out that center post. Or will this cause problems. Anything else I can do to increase flow, with only a dremel . Thanx.

 

[imported_Ron Vogel]

Got the pm, just been a little busy to reply. I just finished up a 2 week show at the merch mart downtown for work, so I took Thurs/Fri off to catch up. It may be a loose plate, but you should take it off to be sure. If you have an extra tb, cut out the post and smooth it down, but epoxy the hole shut. Don't try and use the 97/98 MAF w/o the shaft, it just won't work right. Get a early LS1 maf and put it inline. The 98/99 LS1 is a good match for the standard bore flow capability. You can run it w/o adjustment, but it will run a tad lean, bumping up the frequency +3-5% will get it the same as a stock maf reading. I run a ported LS1 maf on a custom 72mm TB, and it works well, plus it's easier to tune. The stock maf blows.

 

[98 TGP TOY]

OK, thanx for the help ron. Do you know of anywhere to get a used ls1 maf besides ebay. Didnt look like there was much on there and most junk yards dont sell sensors, that I know of.

 

[imported_Ron Vogel]

Check out the camaro and firebird sites, and/or LS1 sites. They are usually pretty plentiful because a lot of those guys upgrade to the truck or Gratanelli units. The stock maf connector is a direct fit with the LS1 also.

 

[imported_Ron Vogel]

Oops, almost forgot...I'm pretty sure that Horist knows a guy who's got stacks of 'em. I remember talking to him about it awhile back.