I still don't get it. 15mpg, tops. that's it. The car was neglected for awhile before I got ahold of it...it's got alot of fresh tune up parts on it, including the fuel filter, but it gets horrible mileage, and while idling, and especially while I floor it, I can see vapor out of the exhaust at all times, smells a little like fuel. It bogs at WOT and just doesn't pull like it used to, kinda like it's flooding. Also, if it idles for a period of time, the plugs foul out. I have no SES codes, and no internal modifications (yet) I'm assuming the 02 sensor is shot, but I used a scanner on it recently and everything appears to within spec, the 02 sensor reading between 450-550 mV. I'm confused

Only thing I can think of is the fuel injectors are leaking. The stock regulator appears to be fine. Anybody have a way I can double check this, or better yet, locate the problem? When I do this, it's also getting a new fuel pump, but I don't think it's related to the problem at all, just a maintenance item. Thanks alot guys!

 

Did you get your injectors cleaned?

 

My buddies TPS sensor went out, which caused him to foul all his plugs, but if your car even makes it down the road, your doing better than he was. Use the scanner to see if you are getting voltage to the tps. With the key in the on position, but not running, open the throttle blades, you should see the numbers move from anywhere between .50 closed to 5.00 all the way open. This is just a range, your numbers won't be exact. If you don't get a reading, it's bad.

 

Nope, everywhere around here is like 'what's that?' or wants to charge an outrageous price for it...and I need to start driving this thing starting next week. There was some injector cleaner run thorugh it recently, a couple times...

I was told a gutted cat could do this. Could it?

I'll check the TPS. but wouldn't that give me a SES light? I think I checked it with the scanner but since I don't have access to it anymore, I'll check it at the TB.

 

450-500mv in closed loop right. If there stuck at 450 you a got a problem. Any reading on the BLMs? I would bet on 02s and egr.

 

Well I think you said it best when you said, "When I floor it I see vapor". Its your lead foot causing the bad gas mileage. But then again, I would love to get 15mpg in the city. Be happy you get that good of mileage. I went from up 40 miles a tank with all new 02 sensors. Gutted cat won't cause any problem, just maybe a more of an exhaust smell. Check for exhuast leaks also.

Travis

 

Listen,
Carbon fouled plugs show an extremely rich condition.
YOUR INJECTORS ARE SHOT!
I can't stress this enough! Most people are overlookin the stockers, they're a POS. They're leaking here and there.
Oh, btw, if you've got carbon failed plugs, check your O2sensors.
If running rich for a long period, they get busted.
Believe it, it happened to me.

 

A very minor header leak on #8 tube has caused me to go from 15mpg to 10mpg in town. The right side has also fouled the plugs.

 

I don't think I have any exhaust leaks, but if I do, they'll dissapear when I put the headers on...

I don't drive it much with my foot to the floor, but when I do, the people behind me aren't supposed to dissapear. When it bogs, I tried that to clear the motor up. the vapor happens regardless of throttle position; just more so when you have your foot down. I don't drive it hard, for the most part.

450-550 mV was in closed loop.

The 15 mpg was on the highway, not in the city. I would be lucky to get 150 miles out of a full tank in the city.

I'm going to pull the EGR valve and check the passages for buildup. At the same time I may just replace the valve, even though there's no signs of anything wrong with it. I'm going to run some cleaner through it shortly before I change the valve so I don't pollute the new one.

Don't remember if I checked the reading on BLM's...

This is why I'm so confused...

 

are you getting 15 in the city??? if you get 15 in the city all the time your more lucky than i am.

 

you posted at the same time as me now i feel like the idiot

 

would a leak from catback to cat cause any loss in power/ gas milage.. i know i didnt get the top cat bolt real tight when i put it on... (ill fix that when i get it out sotrage) but would it make much of a difference having a leak that far down the line?