Engine surging
Thread Starter
Instructor
Joined: Apr 2017
Posts: 133
Likes: 43
From: Manitowoc Wisconsin
Engine surging
Ok guys here’s another question??????
First let me pretense this with I am an LS guy both my other cars are a C5 and a C6 z06.
I am working on a C4 project for my sister. That being said, I have very little experience with the TPI engine. When the car starts it starts fine I got the timing down and throttle position sensor fixed however, when the car warms up it starts to surge I’m guessing vacuum or maybe EGR valve anyone else have this issue that can share some insight on what to look for. There are no codes been thrown and drives fine but when I let off the throttle sometimes it wants to surge so low that it might kill. I’m guessing vacuum leak possibly but I’ve chased pretty much Everyone is there an area that I should look at that’s not as obvious. thanks for your help in advance.
Brandon
First let me pretense this with I am an LS guy both my other cars are a C5 and a C6 z06.
I am working on a C4 project for my sister. That being said, I have very little experience with the TPI engine. When the car starts it starts fine I got the timing down and throttle position sensor fixed however, when the car warms up it starts to surge I’m guessing vacuum or maybe EGR valve anyone else have this issue that can share some insight on what to look for. There are no codes been thrown and drives fine but when I let off the throttle sometimes it wants to surge so low that it might kill. I’m guessing vacuum leak possibly but I’ve chased pretty much Everyone is there an area that I should look at that’s not as obvious. thanks for your help in advance.
Brandon
Race Director
Joined: Jan 2004
Posts: 18,726
Likes: 710
From: Bergen County, NJ
Just my .02.
I had a problem with my '88 a few years back; the idle would go nuts, rev up and down like crazy. I got a remanufactured ECM [electronic control module] and it solve the problem.
I had a problem with my '88 a few years back; the idle would go nuts, rev up and down like crazy. I got a remanufactured ECM [electronic control module] and it solve the problem.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
One more thing to check is the injectors. If you have one or two that are are not injecting fuel, the computer sees low fuel being burned and adds fuel...then it sees too much fuel and starts to reduce fuel. It becomes like a clock pendulum and swings up and down with a greater swing.
Team Owner
Joined: Jul 2004
Posts: 28,472
Likes: 3,290
From: Hartford WI
Ok guys here’s another question??????
First let me pretense this with I am an LS guy both my other cars are a C5 and a C6 z06.
I am working on a C4 project for my sister. That being said, I have very little experience with the TPI engine. When the car starts it starts fine I got the timing down and throttle position sensor fixed however, when the car warms up it starts to surge I’m guessing vacuum or maybe EGR valve anyone else have this issue that can share some insight on what to look for. There are no codes been thrown and drives fine but when I let off the throttle sometimes it wants to surge so low that it might kill. I’m guessing vacuum leak possibly but I’ve chased pretty much Everyone is there an area that I should look at that’s not as obvious. thanks for your help in advance.
Brandon
First let me pretense this with I am an LS guy both my other cars are a C5 and a C6 z06.
I am working on a C4 project for my sister. That being said, I have very little experience with the TPI engine. When the car starts it starts fine I got the timing down and throttle position sensor fixed however, when the car warms up it starts to surge I’m guessing vacuum or maybe EGR valve anyone else have this issue that can share some insight on what to look for. There are no codes been thrown and drives fine but when I let off the throttle sometimes it wants to surge so low that it might kill. I’m guessing vacuum leak possibly but I’ve chased pretty much Everyone is there an area that I should look at that’s not as obvious. thanks for your help in advance.
Brandon
