Hey guys I need some help here, I have a 1997 Chevy camaro z28 with 79k on it. It have been running fine without any problem. I recently just had some Longtube Headers put on now my car drinks a quater tank of gas every two days and I'm shifting at 2000 rpms. The work I have had done is:

Longtube Headers
Cats removed
Egr removed
And for some reason air pump removed.

Since then this car is drinking gas like crazy! I thought that Ithe may need a tune. Others have said that they car runs fine without them. Any help would be greatly appreciated! Oh yea and the check engine light is on also.

You'll need a tune for the EGR delete, and AIR delete.

Okay thanks that's what I thought it was just wasn't 100% sure.

Still doesn't explain the fuel consumption. Tuner can likely spot funny business though.

It didn't start until after the headers was put on. A tune is gonna cost $450, I just didn't wanna get a tune and that don't fix the issue.

if you have a exhaust leak pre-02....than the 02 reading are off showing lean and the PCM commands more fuel

so confirm this is not going on as a tune will not resolve that issue

scan the car and see wtf 02 readings are...

One or both of your header gaskets didn't seal and you have an exhaust leak.

Check for loose header bolts and tighten as needed.

If that doesn't change things......

KW

Before you start doing stuff, How many miles do you drive in 2 days is the question?

I drive 34 miles a day, that's to and from work. So 64 miles in two days.

I checked for leaks there are no leaks, and a new o2 sensor was installed along with the headers. Just the check engine light on that's reading air pump

As noted, because of the EGR and CAT delete, you need a new tune.

The $450 you quote...assume that is on a dyno. That is high $ side for a mail order...

Any tuner is assuming the the car is in solid mechanical condition (i.e. no exhaust leaks, injectors are not leaking, good FP, etc)

your air pump may have been removed because the headers had no provision for the air pump check valves

I gather that with EGR, air pump & CAT delete, LTH emissions is not a issue for you

Where was the needle sitting when you calculated this? These cars have notoriously inaccurate fuel gauges below half tank.

Did you change the O2 sensors during the LT install? Have you checked that they are switching correctly with a scanner?

My gas needle was at the half mark Tuesday morning, Wednesday afternoon it was on empty . I was even shifting gears at 2000rmp still no luck. Yes they was changed out during the the LTH installation. I haven't checked to see if there switching.

I pulled out the computer to get a mail tune and get the codes deleted.

Yes the $450 was for a dyno tune. I found a mail order tune for $150 that's what I went with. I have a couple of buddies with cats deleted so I smelled the fumes for the exhaust, but didn't know it was that bad until I done it myself lol!

What o2 sensors did you put in? Bosch? If so, trash them, and replace with acdelco/denso. Lt1's and Bosch don't mix for whatever reason. You still need a tune though. If no one locally tunes them, I'd recommend Solomon for a mail order.

As others said, o2 sensors, as well as deleting air/egr needing a tune.

But also check for vacuum leaks, exhaust leaks, burned wires, and connectors you may have unplugged during the install.

Well when I did a mail in tune the guy forgot to delete one of the 02 sensors (driver side rear sensor). So the computer was throwing a 02 code and drinking gas Bad. I also had the EGR and pump deleted as well. I got a street and had the code deleted from the PCM and the car runs like ALOT better. Thanks for the help everyone!

Rule of thumb is the top half of the guage reads for 10 gallons and the bottom half for 5 gallons. Once you hit a quarter tank you have maybe 1.5 to 2 gallons left. You need to find out why your SES light is on. Your O2's could be faulty. Any stumbling at midrnage/crusing rpm?

You need to hand calculate your miles per gallon, never trust an F body fuel gage. Pointing at F, that's half a tank, pointing at 1/2, you've got 1/4 left. It touches 1/4, find a gas station now. Fill the tank 100%, go drive a bunch, go fill the tank 100% again, and divide the miles you drove by the number of gallons it took.