Car back fires while Entering boost
Well just got back from tuner shop, We are stumped, we are begining to think it may be a broken valve, or bad coils, we eliminated it being wires or plugs, the 02s are reading fine, no codes are being thrown no lights coming on. I am stumped, I am going to do a compression test tomorrow to make sure everything is ok in that department.
Well just got back from tuner shop, We are stumped, we are begining to think it may be a broken valve, or bad coils, we eliminated it being wires or plugs, the 02s are reading fine, no codes are being thrown no lights coming on. I am stumped, I am going to do a compression test tomorrow to make sure everything is ok in that department.
yea if I gradually get on it it WILL NOT MISS OR BACKFIRE, only when I like floor it is when it does it bad.
Last edited by Eatinstang4life; May 17, 2007 at 11:39 AM.
last night I checked all the ground wires and such. Do you think it would be a good idea to unplug 1 injector wire at a time and drive to try to limit it down to one cylinder?
If you can wind out a gear to your rev limiter, and the car is not missing, then the problem is probably not the actual fuel system right?
Here is what my checklist would be and why:
Fuel pressure: at WOT if it drops more than 10psi it's problematic. Stock FP is like 57psi or something.
Plugs: Too wide a gap, and you will lose spark at WOT. The spark won't survive as it tries to jump the gap.
Valvefloat: Not enough spring pressure will result in your valves not opening and closing properly.
Tuning: If your tune is too rich, the car will run bad.
Grounds, Electrical: Can result in the pcm not having enough power to run, and the car can shut off maybe cut out. This can be pretty rare.
Bad 02's: Fouled out or dead 02's won't switch, and then you will default to running rich.
Here is what my checklist would be and why:
Fuel pressure: at WOT if it drops more than 10psi it's problematic. Stock FP is like 57psi or something.
Plugs: Too wide a gap, and you will lose spark at WOT. The spark won't survive as it tries to jump the gap.
Valvefloat: Not enough spring pressure will result in your valves not opening and closing properly.
Tuning: If your tune is too rich, the car will run bad.
Grounds, Electrical: Can result in the pcm not having enough power to run, and the car can shut off maybe cut out. This can be pretty rare.
Bad 02's: Fouled out or dead 02's won't switch, and then you will default to running rich.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Thanks john thats great info
I checked the fuel pressure its great its not dropping but about 3psi under load still about 63psi under load
I have the plugs about .32 now I will gap them to .28 see how that does.
I don't know how to check the springs other than just replacing them
The tune looks good.
02s are about year old, but they could still be bad I guess
I checked the fuel pressure its great its not dropping but about 3psi under load still about 63psi under load
I have the plugs about .32 now I will gap them to .28 see how that does.
I don't know how to check the springs other than just replacing them
The tune looks good.
02s are about year old, but they could still be bad I guess
Teching In
Joined: Apr 2006
Posts: 15
Likes: 0
Hi there,
please look at this thread and watch video number 3!
http://forums.corvetteforum.com/show....php?t=1699040
I think I have a similar if not the same issue as you. Look at all the parts I already changed and stuff I tested. I still have the issue, I am starting to hate my car!
Keep us posted on what you find out!
please look at this thread and watch video number 3!
http://forums.corvetteforum.com/show....php?t=1699040
I think I have a similar if not the same issue as you. Look at all the parts I already changed and stuff I tested. I still have the issue, I am starting to hate my car!
Keep us posted on what you find out!
Seems like you should run CC0918's or Z06 springs at least for your power level. I'll go with valve float for now. Stock springs will float with the stock cam at 6300...
You need to run more spring anyway, but I'm pretty sure that's your problem. As soon as you get into big boost the valves float. If it was me I'd run 918's, but perhaps other folks might like the Z06 springs.
