ok so saturday i got dyno tuned, everything was fine on the way home saturday night, the sat all day sunday, and it was fine on monday driving to and from work. well tuesday rolls around i go out to my car to go to work, start it up and i immediately realize that it is running really rough and the exhaust sounds like a machine gun not the solid tone it usually is. i shrug it off thinking it is just cold out and once it warms up it'll be fine. well no it didn't, the whole freaking time to work it was running really weird. after work it was even worse, the car even stalled as i was coming to a stop. i started it back up and BAM!!! a freaking check engine light was on. i go home check the plugs cuz it just seems like there is a miss and of course i find that the spark plug on the far right is completely black. these are plugs i just put in saturday before i got dyno tuned. so i put all my old plugs back in, the car idoled a little better but is still running like crap. and this morning on my way to work it was still running pretty rough, any suggestions on what it could be? after work today i will be going to autozone for them to scan the CEL.

 

First, contact the dyno shop. Second, still have warrenty? What mods are done to it and is there any oil on the fourth plug? This is not a good sign the way the car is running. This needs addressed in person immediately

 

Pull the code first, and once you give it to us then we can point you in the right direction. Machine gun sounding exhaust is usually not a good sign though.

Do you still have the stock cat?

 

one must laugh at this......

yet another "professional dyno tune" bites the dust.

i can guess what it is!!!!

I'd call your tuner, tell him hes going to have the chance to re-build an LSJ!

 

I hate to say it, but this is appearing to be true lately. I have no idea why tuner shops think 12.0+ AFR's are good for these cars. Not to say that's what the shop actually did, but it seems that is what's happening. 11.6-11.8 for me all they way.

 

ummm, my warranty is pretty much shot, it was a 3 year/36,000 mile and with my mods it is voided. i didn't see any oil on the any of the plugs, i dont know the firing order tho. i have a 2.6, 60s, 2 step colder plugs, cobra h/e, option b, k&n cai, CA header/2.5" catless downpipe & megan catback (i would add in my meth kit but it is not working at the moment and i was tuned without the meth until i get it fixed then i'll get re-tuned for the meth)

thats a negative on the cat, i went with the CA 2.5" catless downpipe.

i got dyno tuned at Tune Time Performance in NJ. i hope it's not the tune cuz i've seen him do good work.

unforunately i dont have my dyno sheet with me here at work cuz i could tell you the AFR, my wideband gauge is a little off, but when i'm at WOT it says mid 11s.

 

Hmmmm.... Well then.... Get that code for me and I'll try and point you in the right direction. Tune Time is pretty good from what I'm told.

Is there any white smoke or horrible coolant burning smell coming from the exhaust? If so you might be on the verge of a blown headgasket as well.

 

if hes got the WB sittin in the 11's then AFR wise your sittin pretty, could be to much spark and **** whent haywire or it could be another issue.

what code are you pulling?

 

there seems to be some white smoke but nothing out of the oridinary and i have notice that smell. i'll probably go to Autozone for the code at lunch, when i do i'll smell the exhaust.

ok i might have exagerated the sound of the exhaust a little bit, but to me it kind of sounds like a slightly cammed v8. the tone isn't solid like it used to be.

 

If the smoke is white, not gray or blue, then the headgasket might be going. If it is do yourself a favor and stop driving the car. It will save your motor and make life a lot easier and cheaper to repair.

 

i could be wrong but i think the smoke only comes out when i rev it up, not when it is in idol.

 

so its on its way out, not dead yet.

quit reving it!

 

When my headgasket blew, it ran like crap for a little bit and the coolant level lowered a bit. I topped her back off and thought nothing of and just thought the car had a bad day. Then I went to run to the store or somewhere just drively slowly in the neighborhood and BAM a huge cloud of white smoke starting billowing out of my car.

 

i'm not ricer reving it.

well in that case i think i won't drive my car anywhere. i'll drive to Autozone (maybe a 2 minute drive from work) and then after work i'll drive straight home and park it.

 

Don't forget the car will smoke at idle cause of moisture on cold mornings..

 

Here is some useful information if it is indeed a blown headgasket.

https://www.cobaltss.net/forums/2-0l-lsj-performance-tech-47/headgasket-headstud-ordering-information-everyone-34933/

 

thanks for the info man, i'll definately get that code in a couple of hours. i'm hoping it is nothing too serious.

 

I'll keep my toes crossed for you since Rod already has my fingers crossed!

 

haha, i'll take what i can get. thanks again. i guess if all else fails i can do a built engine and swap over to turbo i dont have the money for that kind of thing tho.

 

stop beating on the car.

 

i surprisingly dont beat on it. every now and then i'll get on it on a back road but nothing insane. i enjoy seeing my mpg in the high 20s low 30s.

what do you think it could be Area?

 

i think you popped it.

 

can you elaborate on that?

 

he thinks u popped number 4 find that code, could just be a head gasket, could be alot worse.

 

ooooh, that would be no bueno! going on lunch soon, let ya'll know what the code is when i get back.

ok i am back from Autozone....the code was just a P0172, rich code. a friend was behind me going into town and he said that my exhaust had a good amount of white smoke coming out.