the benchmark:
ls1 98 a4 3.42, hypertech tuning (not fuel curve, but rev limit, shift firmness)
some lt headers(pacesetter), lid, freemods, cutout...
lt1...a4 2.73...cutout...k and n intake
3 races, tied all three times, no pull what so ever

before headers the ls1 raped the lt1
now wiht headers getting 8 codes:
low voltage, too lean , misfire cyl 5

so my questions:
1. what does a lt1 with cut out and intake dyno?

2. why the misfire, whould the lean codes create it?

3. what would solves the problem?

4. what should the ls1 be putting down if it works properrly
with a tune???

the answers i came up with
1. 260-280
2.the shitty extensions on the 02 sensors
3. some ngk 55s and new 02 sensors or real extenders and use the o2s from the back
4. 320/ 330

my friend is not very happy after all his money spent on the headers

 

I had similar problems after my header install. Car felt very sluggish to. I was throwing codes for o2 sensors and missfiring. I ended up buying some new corvette o2 sensors cause the wires are a lot longer and solved everything. My old O2's had about 85K on them and it was nice to get rid of the stupid o2 extensions.

 

A lot of LS1's require tuning after a header install. His A/F ratio is probably way off. The items mentioned already will probably help the condition, but a custom tune may be required.

 

alright, i have joined the crowd. i just installed QTP's headers, ORY, and 02 extensions. my car backfires and sputters down low, then feels a little sluggish in the upper rpm.

so, whats up?? tune?? my extensions looked good, i ran them to the front 02s, but someone said something about running them to the rears?? also, did you just leave the unused plugs open under the car.

ideas and help.... plz.

 

bump!!!!!!!

 

when you change something that drastic you have to tune the car if you are lookin for it to run good. you cant expect to open up the exhaust that much and have the car automaticly feel faster. some cars can do that some cant. i have pacesetters on mine and my friend has them on his SS. its not the headers. the o2 sensors could be bad and the extentions arent crappy at all as you did it right. chances are something wasnt installed right if the tune is ok. check for cut wires. is everything pluged up? maybe one of the wires got burnt on the header. there are way too many variables here. what are all the codes word for word?

 

I *think* I'm experiencing a somewhat similar condition down low lately.. I had my Kooks LTs with Catted Y installed last week or so, and the car feels a bit sluggish below 2k rpms... kinda like a *loose* feeling... past 2k rpms, it screams!

I too have a 98 TA with about 100,400 miles on it now... but no codes!..

I wonder if I need a tune, new O2 sensors or both!!

How much do O2 sensors cost ? anyone have a part # ?

Thanks!!

 

you can buy new 02 sensors at autozone for 50-70$.... can't remember the part numbers

 

thanks.. I got the part numbers:

GM Parts direct has'em for $61 and change each.. GM List is $123 each


LEFT O2 --> 25312197
RIGHT O2 --> 25312196

Front and Back are same.

So, I'd need 4 sensors ?

 

True, very often a spark plug gets whacked/cracked during the install, wires cut, fittings/hoses left off etc.
A tune is the 'ideal' after a header install but not totally necessary in most cases I think.

 

just get the front the rears are for emissions testing, making sure the cats work so dont worry about those. get them from gmpartsdirect the ones from the parts store tend to fail easier. the sluggish feeling that low is normal becuase of tuning and you do loose some low end torque and power after headers sometimes, i think

 

If you get new O2 sensors I would recommend getting the rear one from an LS1 corvette they have the same plugs and the wires are a lot longer. They are only like $5 more a piece then you can get rid of the extensions and dont have to worry about them causing any problems.

 

if you have real extentions u will have no problems. i got mine for free with the headers anyway

 

Can the rear O2 sensors for the F-bodies be used as fronts and are they long enough to be used as front O2s on long tubes (like QTPs, Kooks, Jet Hots etc that have the bungs on the 'inside' (facing the trans as opposed to the doors)) when deleting the rears?

 

u can use the rears in the front, i did when the fronts went to ****

 

is that right, i was told that the left and right were the same on the 98s too.... crap that might be my problem, does anyone know for sure??

i got mine at autozone, i couldn't get the old ones out and i want to get the job finished.

 

same o2's just the wires are different lengths

 

ok i just installed the vette O2 sensors, it is still sluggish and a little wierd jerky feel to it. but it did smoothen it up a bit. do u reccomeend taking off hypertech completely? i just have the top speed, shift firmness, tire height, and thermo. would this be the problem? or do you think there is sumtin else wrong? could be spark plugs? im going to get my car scanned tomorrow and ill update whats goin on.

 

its the ****** sparks like everyone said

 

There is no reason your car, or anyones car would run worse with LT headers installed. The headers arn't the problem. Something either got broken, burnt, or cut. Also... I've heard of people using the wrong bolts to bolt the headers up and cracking their heads or stripping the header bolts out. I'm sure it's a simple wiring problem that you can easily take care of and once you get it fixed you'll be supprised how much LTs wake up the LS1.