dizwiz24

For some reason my car with Ed Wright chip, and hot cam kit installed only gets 14 MPG in the city. I have no idea why. It smells of gas at idle. O2 (Napa) sensors are 5 months old. The old O2 sensors fouled (probably from silicone gasket sealer after the hot cam installed.) causing the car to run so rich (black smoke at idle), and foul the spark plugs to the point where the car won't start.
vacuum leak somewhere? Anybody who has had this problem please help... I should mention the front two spark plugs on passenger side (the easiest to get to) have bone white insulators. No sign of soot like they did b4 when the spark plugs fouled. Fuel pressure is 45 psi, idle is 14 in Hg (a little low probably due to the hot cam). Block learn numbers fluctuate a lot. After a lot of driving they are lower than 128...

gtsyellow

chassis dyno, 3 pulls, wideband 02 in the pipe or in a bung. get the read out, send it to ed & expect a new chip, your prom burn is just a little too rich it seems like. 14mpg in the city is about right however...it's just the smell of gas that's a giveway, maybe you'll get 15-16 after it's tuned. the best part is once it's brought into spec you'll have...more hp...less fouled plugs and a lot less of a gas smell. :)

BIG JIM 54

Sounds like leaky injectors to me. What gives that away is the clean 2 and 4 plugs and the gas smell.

I have a ComCam 501-8 cam and an ADS chip in my car with no other major modifcations and I get 13.5 average on the computer.

I made the mistake once of bypassing my IAT sensor with a 4.8K resistor to keep the ECM in rich cold mode. I saw on eBay that some squid was doing this to his LT1 and was selling "kits" (just a resistor) and swaring he got more performance. All it did for me was make the car sluggish and get 8.5 MPG. Maybe it works on an LT1 but I'm done with it.

BIG JIM


[Modified by BIG JIM 54, 1:53 PM 7/30/2002]

88_vette

I noticed the samething with my ed wright chip. I've had people tell me they gained MPG becuase they were burning my left over fuel. Mine was rich I had raw gas spots on the bumper. If I nailed it anyone behind me would have to wash thier windshield. I've since gone to tuning myself. To much of a hassel to send it back all the time. Even though Ed wright is a great guy to deal with.

Nathan Plemons

My car runs a little rich, at idle. When moving it's dead on. WOT is naturally rich for most power. Overall Ed did a good job on my chip for a first guess.

13-14 mpg in town is about right in line with what I get.

SPD DMN

Back when I had the '92, I had Ed send me a program 3 times before getting one that was close to dead on. You may want to drop fuel pressure down to 40 and see if that helps.

dizwiz24

Ok, I feel better now, I guess. Knowing that others, such as Nathan Plemons, get similar MPG in town. On the highway I get a little over 20 I should add.

It just makes me mad, err jealous, when I see people post topics like 'Gee, these LT-1 are really great, I get 30 MPG' I never saw 30 MPG on the highway or over 17 in the city even when my car was stock.

drive it

Yea-I've never seen that kind of mileage either.....but I think it may have something to do with my right foot..... :lol:

VMAX451

The 30mpg thing only happens if you fill up at a highway exit, hit the highway, hit cruise control and drive 300 miles. Really won't see it except on long highway trips. I've seen close to 30 on mine under those conditions, but get 13-14 mpg city just like you do.