LilJayV10

iTrader: (39)

I hope someone can help me out on this. I've been fighting this for about a year now off and on. I got the car dyno tuned spring of last year after installing a bunch of parts. Afterwards it started to hunt idle real bad and would sometimes die, smells really rich at idle. It makes your eyes water. My gas mileage was about 9mpg. I found the driver side collector was leaking as was my cutout. I fixed the exhaust leaks and put in new 02's. Bosch 13111's. Afterwards the car ran great. Mileage went to 15-16 city driving. After driving it about a month it started doing it again.

Car sat for several months with a valvetrain problem. After I got it running again I found the driver side collector to be leaking again. Fixed it and replaced the 02's. It's still doing it. Mileage is down to around 9mpg again. I got about 90 miles on 1/2 tank of gas(according to the fuel gauge) Hunts idles, dies and its making your eyes water again. It's a pain in the *** to drive, it using that much fuel can't be good for the rings and the wife hates the car because it smells so bad.

I smoked the exhaust system the other day at work and there are no leaks anywhere. I sprayed carb cleaner on the intake when its running and makes no difference. Swapped IAC motors and made no difference.

Everytime I have put new 02 sensors in it the old old ones are covered is soot. I mean like really bad.

I have to get this thing fixed. I'm not throwing the tuner under the bus. I talked to him and said if the car had an exhaust leak when he tuned it, and I'm pretty sure it did, he probably added more fuel than it needed. I am going to take it back to be retuned but I want to figure out what the problem is before I trailer it four hours and find out its not tune related.

At idle in closed loop wouldn't the ECM take over to get to stoich regardless of the tune?

Last year when I fixed the exhaust leaks and replaced the 02's it ran fantastic so the potential seems to be there, however I don't understand if that was the problem why is it back to running so bad now?

This is my setup.

00' Firehawk 6 speed
Stock bottom end
EPS 226/230 cam 112+2
TEA 5.3 1.5 heads w/ 59cc /stock MLS gaskets
Vengeance ported 92 intake/NW 92mm TB
XS LT's, 3in ORYP, flowmaster merge 4in out back into stock SLP dual/dual
SLP 85mm MAF, Fast toys lid, Fast Toys SSRA
28.8 injectors
180 stat

Can someone please help me on figuring out why this thing is using so damn much gas?
I have access to a MODIS scanner at work so I can get all the data from the sensors. I just need to know what to look for.

Hopefully I can get this figured out so I can actually enjoy the car.

Sorry this was so long I just wanted to give as much back information as I could.

Thanks for any help.

Jason

edcmat-l1

iTrader: (10)

Pretty hard to diagnose a problem with no data. If your tuner is worth his weight he should be able to diagnose most any problem it has. If not, find another tuner.

jimmyblue

iTrader: (11)

These cars' tune is only as good as the data coming in.
Many cars have O2 sensor problems especially with long
tubes. When the sensor goes to sleep, the PCM trims
rich and fouls the sensor even worse.

It's worth checking that the heater power is getting to
the sensors, but even that may not be enough. The
(allegedly) best ones I could find still got pretty lurchy
at idle and I live in a warm climate.

LilJayV10

iTrader: (39)

Thanks for the replies. Is there any software out there out there to log data for free?

jimmyblue

iTrader: (11)

There is free software but you'll still pay for the cable.
Anybody's paid-for tune/scan tool will scan for free, so
you might borrow if your local LSx scene is any good.

LilJayV10

iTrader: (39)

I don't mind buying a cable if the software isn't too damn much.

I just don't want to trailer to the car to the tuner only to find out it was something else that was wrong.

Old Geezer

iTrader: (3)

Buy the cable and do the scan/tune/etc. Or, load it on the trailer. Until you do 1 or the other, there's little to no help via a key board.
As in most things... There's no "free lunch"....

LilJayV10

iTrader: (39)

LOL at the no free lunch.

Where can I get the cable and the software to log it?

Thanks.