lt1 running rough
Thread Starter
Registered User
Joined: Apr 2016
Posts: 5
Likes: 0
lt1 running rough I was heading to work yesterday morning my car started up and was running rough bad gas smell rough idle I had an jet performance module chip on the car but took it off when I took it off it was still doing the same thing I would try to give it gas it was hesitating but after a couple of. Minutes it would run fine and than Act stupid again it would die and when I put it Drive be fine but when it goes to reverse it would just die out nowhere but if you try to go and start it again it will not start unless you hold the pedal all the way down go the floor what could this be could it be fuel related or a bad opti or PCM or what ????
Last edited by John Adame; Apr 12, 2016 at 12:32 PM.
Take the vacuum line off the fuel pressure regulator when the car is idling and perfect fuel pressure is 43.5psi, however between 41 and 45psi have been reported and that threshold seems to be fine.
Thread Starter
Registered User
Joined: Apr 2016
Posts: 5
Likes: 0
Ok will check that another thing I went to go and start it. it was completely cold ran fine and everything but when it started to wram up it start to do a rough idle I went to the back to were the tailpipes are at and seen black smoke come out and smells like bad gas and than act's like it had a cam in motor but dose not its a completely stock motor what can that be
Thread Starter
Registered User
Joined: Apr 2016
Posts: 5
Likes: 0
Ok will do and will the regulator make the car run rough and bad idling And raw gas smell and run great at cold but when it get warm run stupid
Trending Topics
Thread Starter
Registered User
Joined: Apr 2016
Posts: 5
Likes: 0
[QUOTE=John Adame;19222367]Ok will do and will the regulator make the car run rough and bad idling And raw gas smell and run great at cold but when it get warm run stupid or is it the o2 sensor that is bad
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
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 Before checking fuel pressure, go ahead and disconnect both O2 sensors and drive around making sure to get up to full operating temp. If the car runs fine then yes, most likely you have bad O2 sensors. Don't mind the check engine light.
As far as fuel pressure goes, pulling the vacuum line off the regulator simulates wide open throttle conditions since there is little-to-no vacuum during this time and the FPR operates on vacuum. You want to check your fuel pressure while the vacuum is disconnected to see what fuel pressure is like when the throttle is wide open.
As far as fuel pressure goes, pulling the vacuum line off the regulator simulates wide open throttle conditions since there is little-to-no vacuum during this time and the FPR operates on vacuum. You want to check your fuel pressure while the vacuum is disconnected to see what fuel pressure is like when the throttle is wide open.
Teching In
Joined: Apr 2016
Posts: 16
Likes: 0
Don't mean to interrupt, but was wondering if you guys would no why when I'm driving when I push the peddle down to about 1500rpm the whole car shakes. Also I seem to have no bottom end power but top end is fine, I've done a tuneup and checked fuel injectors put on a fuel filter and changed o2 sensors. Only code I get is cylinder 3 misfires but I don't see any sparks when I looks at the engine in the dark. Me and my stepdad can't seem to figure out what's going wrong. Hope it's not a bad cylinder or I'm screwed. Also heard it's probably not the pcm because they don't usually cause misfires.