idle problems with cam and Whipple SC
04-11-2003, 01:59 AM
#1
idle problems with cam and Whipple SC
Ya, i sold the bottle for boost. But here is my problem now.
When I start the truck it hunts for idle Big Time. It will rev to 1100rpm on start, which is normal, but then it falls quickly to 500rpms and slowly dies out from there when rpms continue there fall to zero. I have a 208/216 .500 cam which the engine would not have to hunt around for idle on start up before the Whipple SC install. I deleted EGR when I installed the blower, but my block off plates are air tight and the intake block off does not leak vacuum. The only things i can think of that could cause this is another vacuum leak somewhere (but this is highly doubted at this point b/c i have checked every line and hole) or (and this is probably it i just cannot figure this prob. out) there are IAC issues. --When I got the kit used, no throttle body gasket was sent. I made my own gasket, but do not see how idle air is supposed to get into the engine the way the throttle body now mounts to the blower case as there is no hole for the IAC air to get through like was possible in the stock location on the intake manifold. Does anyone have a picture of what the Whipple throttle body gasket that comes with the kit looks like? If IAC is not the problem, does anyone have other ideas as to what may be causing this?
This may help out also: after the truck is warm, it will start up just fine without having to hunt for idle. I thought it learned the problem, but I was wrong - it does this on every start up when the truck has been sitting for a couple of hours. When it does hunt it drops to around 200 (if it just does not die out) and will then rocket back up to around 1200rpm and repeat. If i hold the gas down a little on start up and hold rpms to about 1500rpm and slowly back it down after about 15-20seconds, it will not have to hunt for idle (like me holding the gas on start up forces it to learn something or gives it time to adjust)???
I would honestly appreciate any help. Other than this start up prob. the Whipple is awesome.
When I start the truck it hunts for idle Big Time. It will rev to 1100rpm on start, which is normal, but then it falls quickly to 500rpms and slowly dies out from there when rpms continue there fall to zero. I have a 208/216 .500 cam which the engine would not have to hunt around for idle on start up before the Whipple SC install. I deleted EGR when I installed the blower, but my block off plates are air tight and the intake block off does not leak vacuum. The only things i can think of that could cause this is another vacuum leak somewhere (but this is highly doubted at this point b/c i have checked every line and hole) or (and this is probably it i just cannot figure this prob. out) there are IAC issues. --When I got the kit used, no throttle body gasket was sent. I made my own gasket, but do not see how idle air is supposed to get into the engine the way the throttle body now mounts to the blower case as there is no hole for the IAC air to get through like was possible in the stock location on the intake manifold. Does anyone have a picture of what the Whipple throttle body gasket that comes with the kit looks like? If IAC is not the problem, does anyone have other ideas as to what may be causing this?
This may help out also: after the truck is warm, it will start up just fine without having to hunt for idle. I thought it learned the problem, but I was wrong - it does this on every start up when the truck has been sitting for a couple of hours. When it does hunt it drops to around 200 (if it just does not die out) and will then rocket back up to around 1200rpm and repeat. If i hold the gas down a little on start up and hold rpms to about 1500rpm and slowly back it down after about 15-20seconds, it will not have to hunt for idle (like me holding the gas on start up forces it to learn something or gives it time to adjust)???
I would honestly appreciate any help. Other than this start up prob. the Whipple is awesome.
04-11-2003, 06:22 AM
#2
On The Tree
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Re: idle problems with cam and Whipple SC
During the time I was having intermitent starting problems with my truck I had the same thing happen to my truck. My truck with the stock cam wouldn't idle, I had to keep my foot on the gas just to keep it running. Since the IAC valve is real cheep I just replaced it & the idle problem went away but I still had the intermitent start problems. After about 2 months of putting up with the it I figure out the problem & it ended up being a failed boost-a-pump. After replacing the boost-a-pump the sucker starts up everytime.
04-13-2003, 08:00 PM
#5
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Re: idle problems with cam and Whipple SC
One other thing to check...the intake tube / thottle body connection. I had similar problems with mine hunting all over at idle, but it ran just fine as long as I was accelerating or cruising. One of my hose clamps had moved away from the TB and was only compressing that 6" rubber connector. At idle, all kinda of unmetered air was getting in around the TB because the connector was just kinda pressed in place, not clamped. When I gave it gas, the extra vacuum would snug it up and close off any unmetered air so it ran fine. 5 minutes with the clamp and I was fixed up fine. Kinda felt stupid for not realizing this was the problem in the first place... <img border="0" title="" alt="[Roll Eyes]" src="images/icons/rolleyes.gif" />
Oh, and Y2KSleeper - I don't think $99 for an IAC valve (Autozone and Pep Boys) is in the cheap parts arena, but maybe it is for some.
Scott
Oh, and Y2KSleeper - I don't think $99 for an IAC valve (Autozone and Pep Boys) is in the cheap parts arena, but maybe it is for some.
Scott
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