finished Pacesetter and TSP ORYP install, got a small problem
i have had two cars now with LT's with no tune. They run and drive fine. its just that your not getting everything out of them without the tune..did this make me get a tune? not a chance. I am on the bandwagon that the install does make your car run rich though. Both from gas mileage and smell it is pretty apparent that my cars were running a lot richer after the install...take it for what its worth 
Originally Posted by brad8266
Well good for what your tuner says because it isnt true. Who is your tuner if you dont mind saying?
When you install a set of headers you are increasing airflow through the engine. This increase requires the addition of some fuel in order to maintain stoich AFR (14.7). Without a tune the PCM will be using the same airflow values as before the header install which would result in a lean mixture, but the PCM uses the O2 sensors to provide fueling correction (LTFT's) while at idle and part throttle operation. So at idle or part throttle the O2 sensors will give feedback and the PCM will adjust fueling accordingly and continously. That is why the signal from an O2 sensor is a sine wave, it is always switching back and forth. I went over a year after installing headers before I tuned my car and I never had a single code thrown or any other issue.
The main issue with headers is that sometimes due to the changing of the distance of the O2 sensor to the engine it creates an o2 switching problem.
The only reason my panties would get in a bunch is because instead of helping the guy you gave him bad information. You told him to go waste 500$ on a tune first before doing good troubleshooting when it is completely not needed. Dont give advice on something you dont have direct knowledge of.
When you install a set of headers you are increasing airflow through the engine. This increase requires the addition of some fuel in order to maintain stoich AFR (14.7). Without a tune the PCM will be using the same airflow values as before the header install which would result in a lean mixture, but the PCM uses the O2 sensors to provide fueling correction (LTFT's) while at idle and part throttle operation. So at idle or part throttle the O2 sensors will give feedback and the PCM will adjust fueling accordingly and continously. That is why the signal from an O2 sensor is a sine wave, it is always switching back and forth. I went over a year after installing headers before I tuned my car and I never had a single code thrown or any other issue.
The main issue with headers is that sometimes due to the changing of the distance of the O2 sensor to the engine it creates an o2 switching problem.
The only reason my panties would get in a bunch is because instead of helping the guy you gave him bad information. You told him to go waste 500$ on a tune first before doing good troubleshooting when it is completely not needed. Dont give advice on something you dont have direct knowledge of.
I really was not telling to go get a tune RIGHT NOW, all I was saying was that it sounds like tuning issues, not somethign mechanical- ie brakes etc...
It is his car, his call if he wants to tune, or w/e...
Just trying to help him out...some people will know more than others...I am certainly by NO means a newb...so, enough said...good luck buddy...keep us posted
no panties are bunching at this time
Originally Posted by Magnet
i have had two cars now with LT's with no tune. They run and drive fine. its just that your not getting everything out of them without the tune..did this make me get a tune? not a chance. I am on the bandwagon that the install does make your car run rich though. Both from gas mileage and smell it is pretty apparent that my cars were running a lot richer after the install...take it for what its worth
Originally Posted by Magnet
i have had two cars now with LT's with no tune. They run and drive fine. its just that your not getting everything out of them without the tune..did this make me get a tune? not a chance. I am on the bandwagon that the install does make your car run rich though. Both from gas mileage and smell it is pretty apparent that my cars were running a lot richer after the install...take it for what its worth
My milage was suffering after the install, but we found a vacuum(sp?) leak by the TB. After fixing that & doin the entire Seafoam treatment, my milage is better than before the LT's.
Originally Posted by BIG_MIKE2005
You also got to remember the smell is stronger due no cats, unless your running a catted y. Also mine didn't & still doesn't smell as stong after getting my codes deleted & my leak fixed.
My milage was suffering after the install, but we found a vacuum(sp?) leak by the TB. After fixing that & doin the entire Seafoam treatment, my milage is better than before the LT's.
My milage was suffering after the install, but we found a vacuum(sp?) leak by the TB. After fixing that & doin the entire Seafoam treatment, my milage is better than before the LT's.
Most people also install a ORY or duals when they do the headers, so obviously its gonna smell like fuel. You could run at 16:1 AFR with no cats and it will still smell like fuel everywhere. You should expect a drop is gas mileage with full exhaust anyway, if you gain 30 HP thats almost 10% increase in power. Anytime you do a mod that increases airflow through an engine its going to need to consume more fuel. There is no way around that.
Thread Starter
Joined: Jun 2002
Posts: 669
Likes: 1
From: Amarillo, TX
It was the questionable plug. I replaced it, went on a test drive and it runs perfect now!!! I was actually suprised it was that, since nothing is ever easy when I have a problem
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Verdad Gallardo Thread Starter
Joined: Jun 2002
Posts: 669
Likes: 1
From: Amarillo, TX
Originally Posted by caviness
dont think o2 are interchangable,front ones help motor run,back ones let the computer know if cats are working.
Originally Posted by erikthegoalie
awesome! still, go get a tune....
...........just kiddin hahah
...........just kiddin hahah
Originally Posted by Dr. Jeckel
It was the questionable plug. I replaced it, went on a test drive and it runs perfect now!!! I was actually suprised it was that, since nothing is ever easy when I have a problem
Originally Posted by erikthegoalie
awesome! still, go get a tune....
...........just kiddin hahah
...........just kiddin hahah
Thread Starter
Joined: Jun 2002
Posts: 669
Likes: 1
From: Amarillo, TX
Originally Posted by brad8266
Or just buy the tuning software and do it yourself, its about the price of a single tune and you can always change it whenever you want. Tuning isnt hard to learn either.
And since TSP is is only a couple hours away
, its the best option for me right now.