Started up car.. shoots to redline.
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From: Palmetto, GA
Started up car.. shoots to redline. Started up car.. shoots to redline.
What can cause this? Just got done with a cam install and such... and we started the car and it immeditately shoots to around 3800... and surges around 3800 bad. Then after 3-4 seconds it will fall to about 500.. idle for just a second.. then die.
If it was a vacuum leak it would mantain the high revs? Instead of falling off and then dying would it not? If you touch the throttle at all while its hanging around 500 it will try and shoot back up to around 3800.
Car is a 2000 LS1
Mods are FM14 cam.. dual springs... Ls6 intake.....
Any help soon ASAP pls.
Aside from a huge vacuum leak.. what else could cause this?
http://s93322652.onlinehome.us/problem.wmv Here is a video of the problem. In the second part of the video that is the car revving itself.. not us doing it. We eventually just had to cut it off.
What can cause this? Just got done with a cam install and such... and we started the car and it immeditately shoots to around 3800... and surges around 3800 bad. Then after 3-4 seconds it will fall to about 500.. idle for just a second.. then die.
If it was a vacuum leak it would mantain the high revs? Instead of falling off and then dying would it not? If you touch the throttle at all while its hanging around 500 it will try and shoot back up to around 3800.
Car is a 2000 LS1
Mods are FM14 cam.. dual springs... Ls6 intake.....
Any help soon ASAP pls.
Aside from a huge vacuum leak.. what else could cause this?
http://s93322652.onlinehome.us/problem.wmv Here is a video of the problem. In the second part of the video that is the car revving itself.. not us doing it. We eventually just had to cut it off.
Last edited by SS346Ls1; Jan 18, 2005 at 07:04 AM.
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From: Palmetto, GA
Originally Posted by xssive
Huge leak in the intake somewhere...
Is this the only thing that can cause this?
The car just started up... stayed at 3800 then it fell down to about 500 and was loping for a second..... and then it died again.
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From: Palmetto, GA
Originally Posted by SS346Ls1
Is this the only thing that can cause this?
The car just started up... stayed at 3800 then it fell down to about 500 and was loping and trying to idle... for a second..... and then it died again.
The car just started up... stayed at 3800 then it fell down to about 500 and was loping and trying to idle... for a second..... and then it died again.
Anyone? Someone has to have had this problem before?
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Thread Starter
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From: Palmetto, GA
Originally Posted by 98Mayhem
Vacuum leak.
I want to cover all the options.. aside from a vacuum leak could it be anything to do witha TPS sensor? IAC? Electrical wiring bad? Any type of sensor freaking out?
make sure you didn't pinch something under the intake if you had it off? No a massive intake leak will not keep the RPM's high in a MAF car. It will make it run dead lean once it gets over the initial run rich settings in the PCM used to start the motor and then die because the PCM doesn't see the added airflow through the MAF, making sense?
Launching!
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From: Flower Mound, TX
Originally Posted by SS346Ls1
I want to cover all the options.. aside from a vacuum leak could it be anything to do witha TPS sensor? IAC? Electrical wiring bad? Any type of sensor freaking out?
no, the motor cant revv like that without air. if the TB is closed, there is air getting to it from somewhere else (vaccum leak)
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From: Palmetto, GA
Originally Posted by VSGLS1
Did you have the intake off? Make sure all connections are checked and vacum line also. I saw this happen with a crack on the back of the intake. RPM shot up and then died.
The intake was off the car... we are going to take it back off and go over it good then put it on and try again...
Like I said before I go looking around I want to cover all the options as to do this right the first time..... appreciate it guys.
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From: Palmetto, GA
http://www.cartalk.com/content/colum...anuary/08.html
Found this doing a search.. my coolant temperature sensor broke when we removed the heads.. is it possible since its messed up it would cause a high idle?
Found this doing a search.. my coolant temperature sensor broke when we removed the heads.. is it possible since its messed up it would cause a high idle?
As stated above (more than once), it sounds like a vacumm leak, and the surging is probably the PCM trying to correct it. You posted in another thread that the "map sensor on the back of the intake was broken out of place". I would definitely check that first. If your intake is cracked and a piece of the inake is loose, damaged or missing, that is most likely it. Try that first, then start looking for another causes, IMO.
Shawn
Shawn