LT1 Surging ... what do you guys think?
#1
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.
There is an LT1 at the shop that has a surging issue only when it is HOT (idling for a really long time) ... driving it around it runs flawlessly, until you sit at a light for a minute or two, and it starts to surge.
They checked for a vacumm leak, and there is none. Anyone have any other suggestions as to what it could be??
(btw, this thing is completely stock).
If you need any other info, just shout. Thanks.
There is an LT1 at the shop that has a surging issue only when it is HOT (idling for a really long time) ... driving it around it runs flawlessly, until you sit at a light for a minute or two, and it starts to surge.
They checked for a vacumm leak, and there is none. Anyone have any other suggestions as to what it could be??
(btw, this thing is completely stock).
If you need any other info, just shout. Thanks.
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Last edited by xphantomws6x; 01-15-2004 at 11:34 AM.
#2
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Didn't know you were familiar with the LT1s!
Do you work in a shop or something? or is it just a buddy of yours?
I have no idea what the problem could be, but I'm a novice compared to some of the otehr guys in here lke Gangly or ChrisB
Do you work in a shop or something? or is it just a buddy of yours?
I have no idea what the problem could be, but I'm a novice compared to some of the otehr guys in here lke Gangly or ChrisB
#4
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Originally Posted by Super Mario
Didn't know you were familiar with the LT1s!
Do you work in a shop or something? or is it just a buddy of yours?
I have no idea what the problem could be, but I'm a novice compared to some of the otehr guys in here lke Gangly or ChrisB
Do you work in a shop or something? or is it just a buddy of yours?
I have no idea what the problem could be, but I'm a novice compared to some of the otehr guys in here lke Gangly or ChrisB
Oh, and yes we did check all the plugs, wires, injectors, harnesses, etc etc. Still no clue what it is.
#6
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Originally Posted by TWS
Ditto. Plus check the TPS (throttle position sensor) and O2 sensors, (but those would cause problems when cold also)
I will have them check the TPS and O2 sensors monday ... any other suggestions until then?
Last edited by xphantomws6x; 01-15-2004 at 11:33 AM.
#7
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The part about it running normal until hot throws me a little. Hmm... no carburetor on there? j/k LOL
Well, the Opti-crap is often the culprit when it comes to misses/erratic idle, but operating temp shouldn't play a role in that case.
What year car is it? '95 and up have vented opti's and are less susceptible to carbon tracking and moisture damage.
Well, the Opti-crap is often the culprit when it comes to misses/erratic idle, but operating temp shouldn't play a role in that case.
What year car is it? '95 and up have vented opti's and are less susceptible to carbon tracking and moisture damage.
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#12
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i had a 96 camaro come in with a similar complaint, after driving 20 miles on the highway, the customer would get off the exit ramp, and the car would run hot at the trafficlight, then cool down a bit ashe drove, but once it got hot, it'd miss, run poorly, etc. i ended up putting a waterpump and opti-spark on it, and it was fixed. not to say this is the answer to your problem, but at least check the cooling system, and if you have a scanner, watch the spark.
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It honestly sounds like a burnt plug wire, or a broken plug.
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Rob
1994 Firehawk#319 (slightly modified)
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www.RobsHawk.com
Blown V6
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www.SDFB.org
"Garp bit Bonky"
#15
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Originally Posted by Rob 94Hawk 319
It honestly sounds like a burnt plug wire, or a broken plug.
They haven't gotten a chance to put it in a bay since it has been very busy down there, but when we do and I get it scanned hopefully we will have some more info and maybe something will jump out at us.
Last edited by xphantomws6x; 01-15-2004 at 11:32 AM.
#16
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Originally Posted by xphantomws6x
Normally I would agree ... but it runs flawlessly under normal conditions, which leads my away from a burnt wire or bad plug(s).
We haven't gotten a chance to put it in a bay since it has been very busy down there, but when we do and I get it scanned hopefully we will have some more info and maybe something will jump out at us.
We haven't gotten a chance to put it in a bay since it has been very busy down there, but when we do and I get it scanned hopefully we will have some more info and maybe something will jump out at us.
#17
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i highly doubt its the opti or 02's. My guess is simply carbon buildup in the motor. There is a foam that you can spray into the motor that will get most of the carbon build up out and that will do the trick most of the time. Many vehicles experience this issue and an LT1, being as old as they are now, start to experience it a lot. When my LT1 was torn down and rebuilt, there was TONS of carbon buildup inside the motor and on the valves. Our 2002 Yukon had the same problem(surging when it sat at idle for even a short amount of time once warm) and that took care of it immideately(sp?)and we havent had the problem since.
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I will bet my life on this. ITs your EGR valve on the back of the intake. Im 100% sure. I had a terrible surge problem with my impala. You need the 96 F- body six-speed EGR Valve.
You problem has been solved.
You problem has been solved.
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On another board, there was a thread about hot engine surging at idle and low RPM. One of the suggestions was to replace the IAT sensor. It's about $8 at most part stores (BTW - the new part is in a brass housing, not OEM plastic, but it fits and works). This, the Seafoam (Carbon cleaning) treatment, and cleaning my Throttle Body (man that thing was filthy) cured the problem in my 94Z.
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#20
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there is a little tiny part that controls the spark that mounts next to the coil. It actualy sits right against the head. Driver side. You need to move this off of the head and relocate it. When it starts getting hot it will malfuncion. good luck.