after installing my longtubes and ory-pipe my truck runs like poo. BUT REMEMBER, i don't have my re-tune yet. It is comming Tuesday. I can smell fuel passing through my exhaust, is drinks fuel, and is a lot slower. I was running a 15.5@93 now i am running a 16.29@90. Hopefully i will be below 15.5 when i get my retune or else i would have lost power by installing long tubes.(which i don't think is possible, i know long tubes should lower my 1/4 mile time)

 

What is it doing exactly? Sputtering and missing? Or just slower in the 1/4? Do you have a way to check for codes? They don't always trip the dash light. My front drivers side O2 sensor wire was touching one of the LT's and my truck almost wouldnt run until I got over 2800rpm and got into open loop where it ignores the O2 sensor. Explain a little better "runs like crap"

 

I just noticed your sig. If you have a true dual 3" setup you have about zero back pressure. You're gonna sacrifice some low end Tq for that. Even getting the tune tweaked may not solve that. May be time for a converter....

 

its not a true dual system. I got back pressure, cause it will jump on the line. But, when i give it throttle it gets up to around 5000rpm and begins running wierd. These codes are what i've got so far....P0054, P0060, P0141, and P0161. The last two codes always pop up, the first two codes rarely come on. I have an interceptor scan gauge by the way.

 

Did you disconnect the battery when installing your LT's? If not, try that for about a half an hour, sometimes it helps to reset the sysem.

 

The last 2 codes have to do with O2 sensor heaters. It's the back O2's throwing these codes.

The other 2 dont even show on the list I looked at. I will have to keep digging.
http://www.geocities.com/dtmcbride/h...bd_dtc_gm.html

 

Read this:
https://www.performancetrucks.net/fo...ighlight=P0054

Also, these codes should have nothing to do with running weird at 5000rpm. The PCM is reading the fuel tables and not the O2 at that rpm. These codes would effect idle and part throttle driving (in town) All 4 codes are dealing with the O2 sensors.

 

Welcome to the world of LT's. I couldnt imagine trying to explain the problems after my LT install to a tuner via mail/phone none the less getting them fixed. You really need to get HPtuners or get with someone who does and get some live scanning and then tuning. I would make sure there are no exhaust leaks first(I had some) then if that ist the fix(which it wasnt for me) I would pick up (2) Bosch-1311 oxygen sensors which are rear o2 sensors for a 02 Vette. Put these in place of your stock front o2's. You also need (2) AC-Delco PT919 pigtails so the connectors fit. This was the fix for mine a year ago and numerous here recently. There are numerous threads about this if this is your problem. First things first you need to get some scanning done.

 

cool, thanks guys

 

Yeah you need tuning software for your self!! The only other thing I could suggest, if you don't want to tune yourself, is to get a scanner so you can at least identify the problems and send them back to your mail order tuner!!