High Idle Issue .............
Thread Starter
On The Tree
Joined: May 2002
Posts: 143
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From: Irving, Tx
Re: High Idle Issue ............. The idle will drop down to 650, only after sitting
at a stop for a while, set screw adjustment looks fine (never adjusted). As far as asr servo, I don't have one (no cruise control) right?
Help!!!!
at a stop for a while, set screw adjustment looks fine (never adjusted). As far as asr servo, I don't have one (no cruise control) right?
Help!!!!
Re: High Idle Issue ............. If you have access to Atap or EFILive you could log some data and see if you get any clues from that. For example, a bad engine temperature sensor might tell the PCM the engine is cold all the time resulting in the PCM keeping the engine on fast idle for warm-up.
Thread Starter
On The Tree
Joined: May 2002
Posts: 143
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From: Irving, Tx
Re: High Idle Issue ............. When we auto tapped the car we looked at the IAC motor at idle, cruse, and w/ the ac on, seemed to be working fine. He is pulling up the last time we auto tapped to look at engine coolant temp, but I think it was fine only because the o2's were reading normal (from all other times) not rich. But the ONLY sensor I haven't changed is the engine coolant temp sensor. Thanks and please keep the ideas coming!
JD
JD
Thread Starter
On The Tree
Joined: May 2002
Posts: 143
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From: Irving, Tx
Re: High Idle Issue ............. The idle stays around 1100 to 1200 with my foot off the gas coming to a stop, sometimes as high as 1600, but after a few seconds it drops to 650. On cold start ups it idles real high (1600) for a while before it even drops to aroud 1000. On auto tap with 0.0% on the TPS it shows 1500 to 1600. As far as the pintle sticking out, it matches a new one I bought (2000 style) that made the problem worse! I tried a different T.B. and no difference. Also have done the idle relearn a few time and no dice. On a auto tap pass after letting off the gas (tps @ 0.0) the readings are:
36 (iac) 1100 (rpm) 189 coolant temp
37 - 1600
45 - 1700
76 - 1693
22 - 600
Getting back in it at 15.7(tps) 1379 (rpm) iac (67)
15.7 1763 iac @ 134
Does this tell you guys anything?
JD
<small>[ April 24, 2003, 10:02 AM: Message edited by: JASON ]</small>
36 (iac) 1100 (rpm) 189 coolant temp
37 - 1600
45 - 1700
76 - 1693
22 - 600
Getting back in it at 15.7(tps) 1379 (rpm) iac (67)
15.7 1763 iac @ 134
Does this tell you guys anything?
JD
<small>[ April 24, 2003, 10:02 AM: Message edited by: JASON ]</small>
Thread Starter
On The Tree
Joined: May 2002
Posts: 143
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From: Irving, Tx
High Idle Issue ............. Other than the IAC and PCM, what other sensors have an effect on idle? I do not have a intake leak (put new gaskets) and I have changed O2 sensors, MAP, MAF, and now the PCM! Still have high idle. I need some HELP PLEASE!!!
Thanks, Jason
Thanks, Jason
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Verdad Gallardo Re: High Idle Issue ............. Looks like the PCM is commanding the fast idle through the IAC. You could verify this by unpluging the IAC and just using the throttle screw to set the idle speed. Might also check the ignition timing during these times that it is idling fast. Too much timing can cause a fast idle that comes down very slow, serch on "cruise control effect." Is this car running stock tuning? Sometimes people jack up their low rpm timing too much to help with a big cam and it causes the cruise control effect.
Teching In
Joined: Apr 2003
Posts: 1
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From: mpls.mn.
Re: High Idle Issue ............. you may want to look at the rear of your intake manifold, there is a o ringed area where your map sensor and your vacume for the power brakes is located, i have seen several that were cracked {new in box ls-6} also i have heard of some leaking past the o ring i have been siliconing this area to eliminate this possible vacume leak.good luck.
Thread Starter
On The Tree
Joined: May 2002
Posts: 143
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From: Irving, Tx
Re: High Idle Issue ............. My car is a bolt on car and has no cam, I did have tuning but only to turn off the EGR, Air, etc..... I unpluged the IAC and with the set screw can make the car idle where is suposed to (650).
The plunger on the iac moves with the key on (SLOW) so it appers to work? So with the iac unpluged and the car idling right does this mean I have a bad iac? If so when I tried other T.B.'s why did the car do the same thing? Also I was told to buy a 2000 style iac and that did not work. Do I need to buy one for a 98 and try it?
Jason D
The plunger on the iac moves with the key on (SLOW) so it appers to work? So with the iac unpluged and the car idling right does this mean I have a bad iac? If so when I tried other T.B.'s why did the car do the same thing? Also I was told to buy a 2000 style iac and that did not work. Do I need to buy one for a 98 and try it?
Jason D
Re: High Idle Issue ............. When you disabled your EGR did you block off the air passage to the exhaust? Also, the timing maps are very different for non EGR cars. You can download some tunes from the LS1 Edit library. Try looking at non EGR year cars (2001&2002). Take a look at your timing when the car is rolling and when it's stopped. IAC on my '00 SS like top be around 30 counts with the engine warm (180º) idling in park.
Good luck,
Richard <img src="https://ls1tech.com/threads/images/graemlins/smile.gif" alt="" />
Good luck,
Richard <img src="https://ls1tech.com/threads/images/graemlins/smile.gif" alt="" />
Staging Lane
Joined: Jan 2002
Posts: 87
Likes: 0
From: Patchogue, New York
Re: High Idle Issue ............. hey jason I am having the same problem with my 99 SS. About a month ago, I was having a idleing issue. What happened was, when the car was cold, I would start it, the car sounded like it had a huge cam in it, the idle would go up and down and the temp gauge would flick up and down. Once the car warmed up it idled fine. I changed everything on the car and it still did it. I finally brought it in and they replaced the computer and that fixed the problem. Once I got the car back, I have been having the same issues as you coming to a stop with the idle going up and then coming down slow. It doesnt happen all the time, but it does it whenever it feels like it. So TTT for you.
