[03Black2v]

I searched and found nothing.

Alright, so lately my car has been getting terrible gas mileage. I mean around like 8-10mpg through the city. It shouldn't get that bad should it? I also was riding around at 11-11:30 one night and I floored it and around 4k rpm it sounded like it didn't want to go any higher.

Is it bad COPs or coil packs? I changed the spark plugs and air filter the same day but didn't replace the coil packs or anything else. I'm thinking COPs which is going to suck since they're really expensive.

[86er]

lazy maf, dying fuel pump. Any way to read live date or check fuel pressure?

[03Black2v]

I could probably find someone or a shop that does it.

[03Black2v]

It did sound a little better today when I took it to about 3.5k.

[Shaun03GT]

Has it rained at all? Sometimes after it rains one of my COPs gets wet and misses. But like 86er said, fuel pimp, maf etc. Try doing some live data

[Supercharged02GT]

Sounds like your exhaust could be getting plugged I had a cat go bad and had the same results as ur having

[03Black2v]

Originally Posted by Shaun03GT Has it rained at all? Sometimes after it rains one of my COPs gets wet and misses. But like 86er said, fuel pimp, maf etc. Try doing some live data

Nope. Hasn't rained lately.

Originally Posted by Supercharged02GT Sounds like your exhaust could be getting plugged I had a cat go bad and had the same results as ur having

Hm. I might do the live data check and see what comes up, if nothing then i'll get my exhaust checked out.

[86er]

quick maf test. Start run the car at idle. Pay attention to how it runs if its rough, smooth, slight wondering idle etc. Then unplug the maf, see if anything changes. If nothing changes, your maf is faulty, if it changes, move on to your next thing to check

[03Black2v]

I've noticed that it does idle kind of like it has really small cams. I'll check the maf tomorrow after school when I get home.

[laoutlaw01]

I'm experiencing the exact same thing bud. I took all my coil packs out last nite and check them with a ohm meter per specs and they all checked out ok. Also checked the injectors with a ohm meter and did the old screwdriver to the ear trick and they checked out ok. So then I cranked the car and started pulling the connectors on the packs and injectors one by one and that checked out ok. Thought maybe my diablo chip has gone bad somehow so I pulled it and stuck a spare in there and then no chip at all,same thing all three ways. Ok so Tommorow I'm hoping I don't have to work over so i can do the exhaust.I have all stock exhaust with the mufflers cut off with pipe in there place. I also have some flowmaster knock offs laying in my shop so I'm going to cut the convertors off,put pipe in there place and weld the flopros in place of where the stock mufflers used to be. Kinda like a elcheapo catback and o/r x . Don't laugh I'm a father of two and I enjoy spoiling my kids more so this is going to be a temporary fix till income tax time. I hope it fixes it. I'm kinda ruling out the fuel pump because it was replaced prolly 8,000 or so miles ago with a high flow of some type right before I bought it.I know this because a friend of mine did the actual install on it. Good luck and keep us updated as I will to ,hopefully one of us will run down this bug.

[03Black2v]

I have stock headers, and midpipe with weld in flows. What are you going to do to check if it's your exhaust?

[number1gt]

I think he meant he's going to cut his cats out

[laoutlaw01]

Yes I'm cutting my cats out and weld in knockoff flownasters so it wont sound completly stupidit will be just temporary either way till income tax time.

[03Black2v]

Just did the maf test. Soon as I unplugged it, the rpm's dropped low then went back up and idle'd just like it did before. I'll check it again tonight with a friend to make sure I was hearing right lol. If it is the reason, should I just get an oem replacement or what? i've been thinking about an rai soon too, so it could be time to upgrade both.

[laoutlaw01]

I didn't get a chance to cut my cats yet but I did use my laser thermometer on the cats after a short drive home from the gym last night. Front cats were at around 220*,back cats were at around 420* and the pipes themselves about a foot behind cats was at 145*. I know the back cats are supposed to be hotter but 400*?

[Eagle2000GT]

I had a Chevy truck that broke down on the interstate about 60 miles from home. I limped into the local dealership. They did a lot of repairs and the truck ran pretty much the same. Missing out, low gas mileage, etc. They told me it was the new spark plugs that I had put in it. They were completely incompentent. I was angry so I took it home anyway. I made it maybe 10 miles before it stopped running. I refused to have it towed back to the dealership instead paying to have it towed 50 miles to an independent shop that I use all the time. My problem was a plugged cat. They confirmed it by removing the 02 sensor and pumping air into the exhaust pipe.

You could try pumping air into your exhaust. If it flows out the back the cat isn't plugged. If it pressurizes it is.

[laoutlaw01]

That would work if all the valves shut on that side of the motor. If not it would just flow threw the heads up the intake and right out the throttle body. Correct me if im wrong

[04 BEAST]

Originally Posted by 03Black2v Just did the maf test. Soon as I unplugged it, the rpm's dropped low then went back up and idle'd just like it did before. I'll check it again tonight with a friend to make sure I was hearing right lol. If it is the reason, should I just get an oem replacement or what? i've been thinking about an rai soon too, so it could be time to upgrade both.

I did that check also but soon as I unplugged mine my car died!!

[SON1C]

02s?

[laoutlaw01]

Originally Posted by SteeD43 02s?

Mine are supposedly turned off with the diablo chip that's in my car. That is the next thing on my list to replace with a SCT handheld. It was in the car when I bought it but I do not know exactly what's on it.