L98 Engine Backfire
Thread Starter
Instructor
Joined: May 2011
Posts: 213
Likes: 0
From: Miramar Florida
L98 Engine Backfire
After replacing two bad lifter in my engine, I got it reassembled and set the timing to 6*. When I drive or rev the engine to normal drive speed I get back firing in the engine. Is this do to the timing being off slightly. It seems to run good at idle. I have not set the idle air or TPS but I don't think either of these will effect the engine back firing. Am I on the right track?
Thread Starter
Instructor
Joined: May 2011
Posts: 213
Likes: 0
From: Miramar Florida
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
it is only thing that tells the computer how far throttle is open so it can adjust fuel and timing to suit
If you have foot @ 50% throttle but TPS is only showing throttle 25% open
then you will have problems
Thread Starter
Instructor
Joined: May 2011
Posts: 213
Likes: 0
From: Miramar Florida
I will be sure to set the TPS, first thing. However I did not seem to have any problems with where it was set prior to replacing the bad lifters.
Safety Car
Joined: Sep 2001
Posts: 4,134
Likes: 531
From: Glenbeulah Wi
After replacing two bad lifter in my engine, I got it reassembled and set the timing to 6*. When I drive or rev the engine to normal drive speed I get back firing in the engine. Is this do to the timing being off slightly. It seems to run good at idle. I have not set the idle air or TPS but I don't think either of these will effect the engine back firing. Am I on the right track?
Thread Starter
Instructor
Joined: May 2011
Posts: 213
Likes: 0
From: Miramar Florida
OK, I set the minimum idle air and the TPS. I'm still getting the backfire, I double checked the timing and it was slightly off by one degree so I got set to 6*. I'm going to pull my valve covers and set lash on the valves again, hopefully this will correct the problem.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
2027 Corvette vs The World: Every Model vs Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!
Michael S. Palmer
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!
Joe Kucinski
Thread Starter
Instructor
Joined: May 2011
Posts: 213
Likes: 0
From: Miramar Florida
Success, I got the backfire issue resolved, I went back through and reset the lash on all the valves and that corrected the problem. Now the engine runs smooth, almost perfect. Only issue I have now is I'm still hearing a ticking noise as I drive. Now that I've replaced the lifter, I can rule that out, either way it's not quite the same sound as I heard with the bad lifters. I can hear the injectors fire when I have the hood open but I wouldn't think they would be loud enough to hear when driving. Any ideas, I'm thinking it is something external from the engine. I can only hear it when I drive.
Thread Starter
Instructor
Joined: May 2011
Posts: 213
Likes: 0
From: Miramar Florida
Another thought just remembered that when I was under the hood with the engine running I could feel pressure blowing at the EGR pipe when I revved the engine. Maybe the ticking sound is an exhaust leak. Would a leak at the EGR pipe cause the ticking noise when driving?
