Idle Problem 96 LT1
Thread Starter
1st Gear
Joined: May 2009
Posts: 1
Likes: 0
From: Cortlandt Manor New York
Idle Problem 96 LT1
I have a 96 LT1 with an idle problem. I just had the front seals replaced, water pump changed, radiator replaced, rotor cap and wires replaced. When the car is first started it idles smoothly. After a few minutes the idle starts to surge for a few seconds and returns to normal. This is akin to the AC cycling on and off. We turned the AC off and this did not stop the problem. This only started after I had the car serviced. We checked for vacuum leaks, cracked hoses etc. We spayed carb cleaner to try to find the problem but have been unsuccessful in locating the problem. The car has 51,000k and runs great.
Any suggestions???
Thank You
Anthony
Any suggestions???
Thank You
Anthony
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
No answer but if you find out what is causing it let me know.
I have the same problem on my '96. I had the very same repairs done you did and it hasn't been right since. I am starting to wonder if the stock opti doesn't like the replacement cap and rotors that are out there. I have chased this thing for months, replaced every part I can find that may be causing it and no luck. It's still there in closed loop.
I have the same problem on my '96. I had the very same repairs done you did and it hasn't been right since. I am starting to wonder if the stock opti doesn't like the replacement cap and rotors that are out there. I have chased this thing for months, replaced every part I can find that may be causing it and no luck. It's still there in closed loop.
Advanced
Joined: Jul 2005
Posts: 59
Likes: 0
From: Harrisburg North Carolina
I had the same problem with my 93 a couple of years ago. I replaced the EGR valve and it seemed to correct the rough idle.
Its an easy and cheap place to start. I picked one up for $28 from GM.
Its an easy and cheap place to start. I picked one up for $28 from GM.
Team Owner
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
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Did you physically remove the entire TB or just spray TB cleaner in it? It's best to remove the entire assembly for thorough cleaning.
Get a large, plastic Tupperware bowl, a can of TB cleaner, some shop towels, and old toothbrush, and a can of idle air control (IAC) cleaner. Then, remove the TB assembly, spray it down real good with the TB cleaner, and go to town with the shop towels and toothbrush.
Remove the IAC motor pintle and clean any traces of carbon from the spring. That's likely your problem right there, carbon build-up. Be sure and replace the IAC gasket with a new one or cut one from gasket paper. Make sure you wet the gasket with a dab of motor oil before bolting it back to the TB housing to ensure a tight, leak-free seal.
I clean my TB in this manner once a year. It really mellows the base idle, improves throttle response and fuel economy, too.
Get a large, plastic Tupperware bowl, a can of TB cleaner, some shop towels, and old toothbrush, and a can of idle air control (IAC) cleaner. Then, remove the TB assembly, spray it down real good with the TB cleaner, and go to town with the shop towels and toothbrush.
Remove the IAC motor pintle and clean any traces of carbon from the spring. That's likely your problem right there, carbon build-up. Be sure and replace the IAC gasket with a new one or cut one from gasket paper. Make sure you wet the gasket with a dab of motor oil before bolting it back to the TB housing to ensure a tight, leak-free seal.
I clean my TB in this manner once a year. It really mellows the base idle, improves throttle response and fuel economy, too.
Safety Car
Joined: Dec 2007
Posts: 3,616
Likes: 5
From: Sandhills of North Carolina
If they do I'm missing mine and one didn't come with the new IAC I bought a while back.
Maybe I need to make one for it. I have the same type idle issue.
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
I have a 96 LT1 with an idle problem. I just had the front seals replaced, water pump changed, radiator replaced, rotor cap and wires replaced. When the car is first started it idles smoothly. After a few minutes the idle starts to surge for a few seconds and returns to normal. This is akin to the AC cycling on and off. We turned the AC off and this did not stop the problem. This only started after I had the car serviced. We checked for vacuum leaks, cracked hoses etc. We spayed carb cleaner to try to find the problem but have been unsuccessful in locating the problem. The car has 51,000k and runs great.
Any suggestions???
Thank You
Anthony
Any suggestions???
Thank You
Anthony
Follow the sequence in your FSM for resetting the IAC.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Did you check the plastic hose connectors?
There's a plastic vacuum hose fitting on the passenger side of the intake, under the CORVETTE cover that could be cracked and leaking. On my 96, the hose was good but as soon as touched the little hose barb it fell apart.
I'm assuming the Opti Vent hoses (2) were reconnected, right?
Jake
West Point ROCKS!
There's a plastic vacuum hose fitting on the passenger side of the intake, under the CORVETTE cover that could be cracked and leaking. On my 96, the hose was good but as soon as touched the little hose barb it fell apart.
I'm assuming the Opti Vent hoses (2) were reconnected, right?
Jake
West Point ROCKS!
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