Help, running horrible
Thread Starter
Staging Lane
Joined: Mar 2004
Posts: 72
Likes: 0
From: Tallahassee, FL
Help, running horrible Ok, my buddies took off my Longtubes and replaced with stock manifolds and catalytic converters. They also took off my jantzer tb and put a 99 stock tb on the car. I don't have any exhaust from the catalytic converters back right now, have to get the y pipe and catback welded on. Anyways, after all this the car runs absolutely horrible.
If i get on the gas in any gear it just pops and bucks and just sounds bad. It will rev up but it almost sounds like the car is backfiring the entire time. Absolutely no power at all. When the car isn't in gear at idle it sounds fine, i can rev it up and it doesn't backfire or sound nasty at all, only when the engine is under a load.
My car is an 02 and i put the 99 tb on it, i know they are a little different and my cable is loose, but i'm sure that wouldn't cause this problem. I'm not throwing any codes either except for the normal ones (no rear o2's or AIR). Car ran fine this way before the LT's and TB came off. Please help
If i get on the gas in any gear it just pops and bucks and just sounds bad. It will rev up but it almost sounds like the car is backfiring the entire time. Absolutely no power at all. When the car isn't in gear at idle it sounds fine, i can rev it up and it doesn't backfire or sound nasty at all, only when the engine is under a load.
My car is an 02 and i put the 99 tb on it, i know they are a little different and my cable is loose, but i'm sure that wouldn't cause this problem. I'm not throwing any codes either except for the normal ones (no rear o2's or AIR). Car ran fine this way before the LT's and TB came off. Please help
Launching!
Joined: Nov 2001
Posts: 294
Likes: 0
From: San Jose, CA
What do you mean by the wire is loose? I would try install the your other tb and if it works ok and test & check 02 sensors to see if their ok. If you cant figure it out just take to your local LS1 specialist and have them diagnose it for you.Then just do repairs your self.
Thread Starter
Staging Lane
Joined: Mar 2004
Posts: 72
Likes: 0
From: Tallahassee, FL
Originally Posted by DravenMyers
What do you mean by the wire is loose? I would try install the your other tb and if it works ok and test & check 02 sensors to see if their ok. If you cant figure it out just take to your local LS1 specialist and have them diagnose it for you.Then just do repairs your self.
I guess i could reset the pcm. I have a predator, should i just reinstall my stock tune or should i reset the pcm completely? Also, how do i reset it if that's what i need to do?
Last edited by Bryan 02TA; Mar 2, 2005 at 10:01 PM.
Originally Posted by Bryan 02TA
well the 98-99 throttle bodies are different b/c of the cam lobe. It makes the throttle cable loose so if i hit the gas at WOT i won't get the full 100% WOT. I either need to get the 2000+ throttle body or the cam lobe off one.
I guess i could reset the pcm. I have a predator, should i just reinstall my stock tune or should i reset the pcm completely? Also, how do i reset it if that's what i need to do?
I guess i could reset the pcm. I have a predator, should i just reinstall my stock tune or should i reset the pcm completely? Also, how do i reset it if that's what i need to do?
Trending Topics
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 Thread Starter
Staging Lane
Joined: Mar 2004
Posts: 72
Likes: 0
From: Tallahassee, FL
ok, i turned the key on and unplugged the 2 pcm fuses under the hood, then turned the key off and waited 10 minutes to plug them back in. If that is the correct way to reset the pcm, it didn't work. Lemme know if that is how you do it and if i have any more options?
I turned the key to on, removed the fuses and then left it for ten minutes (with the key still in the ignition) You may not notice any difference, I did but you never know, just something else to try. Did you check your plugs and wires yet?
Okay then how come all the shops i talk to and my computer programmer says to disconnect the battery for 15-30 mins to reset and it clears codes. ive done this several times on newer cars and works great just the computer relearns idle and fuel trims.
Thread Starter
Staging Lane
Joined: Mar 2004
Posts: 72
Likes: 0
From: Tallahassee, FL
ok, just tried a different throttle body off on 01 car, that didn't help any either. i am at a loss here, i have no idea what could cause this. It feels and sounds like a misfire but i'm not getting a misfire code. DAMN!!!
TECH Addict
Joined: Nov 2001
Posts: 2,003
Likes: 0
From: Live Oak, FL - in the woods where the creatures lurk.
10 minutes of power disconnect (battery) usually will reset the codes. The capacitors will usually drain w/o power by then, at least that's been my experience w/my car. Question: I guess I missed something, are you putting your car back to stock to sell it? 
I've seen a couple 'a posts lately where folks have removed mods and had a hard time getting the car (engine) to run correctly.
I've seen a couple 'a posts lately where folks have removed mods and had a hard time getting the car (engine) to run correctly. TECH Addict
Joined: Nov 2001
Posts: 2,003
Likes: 0
From: Live Oak, FL - in the woods where the creatures lurk.
I'm trying to think this out...you put the stock exhaust manifolds back on, IF you have deleted AIR and EGR, fine, but have you plugged/blanked off the the inlets for the stock system? Sorry if this sounds assinine, just trying to dig the details, see if there is an air leak somewhere.
Launching!
Joined: Nov 2001
Posts: 294
Likes: 0
From: San Jose, CA
Originally Posted by flippincamaro
Okay then how come all the shops i talk to and my computer programmer says to disconnect the battery for 15-30 mins to reset and it clears codes. ive done this several times on newer cars and works great just the computer relearns idle and fuel trims.
Thread Starter
Staging Lane
Joined: Mar 2004
Posts: 72
Likes: 0
From: Tallahassee, FL
Originally Posted by gwj
I'm trying to think this out...you put the stock exhaust manifolds back on, IF you have deleted AIR and EGR, fine, but have you plugged/blanked off the the inlets for the stock system? Sorry if this sounds assinine, just trying to dig the details, see if there is an air leak somewhere.