bad injectors?
Team Owner
Joined: Jul 2004
Posts: 28,424
Likes: 3,276
From: Hartford WI
Team Owner
Joined: Jul 2004
Posts: 28,424
Likes: 3,276
From: Hartford WI
Le Mans Master
Joined: Feb 1999
Posts: 6,470
Likes: 2
From: levittown pa. usa Even a bad day with my `Vette, is better than a good day at work
St. Jude Donor '10
Never fell for that one again. 
Last edited by kenv; Jan 9, 2011 at 09:05 PM.
Thread Starter
Burning Brakes
Joined: Aug 2010
Posts: 833
Likes: 1
I'll have to try that one!
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
My 86 precats were plugging up. I could go around town fine, but on a hill, I couldn't catch a kia.
I changed the exhaust, and wow what a difference.
One thing I tried that seemed to work great was to remove the exhaust manifolds and port the flanges a little bit to match up with a gasket. That seemed to help a lot with the exhaust.
I bought an exhaust system from a friend, and one of the cats was breaking up. The system has dual pipes with dual 3 way cats with no precats.......huge difference in the power department.....
So now, I am making a new exhaust that is basically the Y pipe with two bullet cats, no precats, a test pipe instead of a main cat, and 91 convertible mufflers.
Those huge mufflers look like I am trying to quiet down Godzilla I ended up putting a 383 in it that I got at a wrecking yard for $300. Now I need a trans..........
I changed the exhaust, and wow what a difference.
One thing I tried that seemed to work great was to remove the exhaust manifolds and port the flanges a little bit to match up with a gasket. That seemed to help a lot with the exhaust.
I bought an exhaust system from a friend, and one of the cats was breaking up. The system has dual pipes with dual 3 way cats with no precats.......huge difference in the power department.....
So now, I am making a new exhaust that is basically the Y pipe with two bullet cats, no precats, a test pipe instead of a main cat, and 91 convertible mufflers.
Those huge mufflers look like I am trying to quiet down Godzilla
I ended up putting a 383 in it that I got at a wrecking yard for $300. Now I need a trans..........
Last edited by coupeguy2001; Jan 24, 2011 at 10:12 PM.
Team Owner
Joined: Jul 2004
Posts: 28,424
Likes: 3,276
From: Hartford WI
Thread Starter
Burning Brakes
Joined: Aug 2010
Posts: 833
Likes: 1
Car still isn't running right. I replaced the ICM and the plug wires and that did make it run better but the problems are still there. The other day I started it and I could here the miss at idle, out of the left muffler. I thought this was strange because the exhaust goes into a y and it should affect both. I also went for a ride with the fuel pressure gauge sticking up out of the hood, and the pressure stayed strong. However, When I turned the car off, the pressure dropped down to 10 psi in about 15 or 20 mins. I don't think that's normal. I also unplugged the vacuum line from the EGR and capped off the end and went for a ride, and it ran great until i started to come back home and same problems. Plus with the EGR unplugged it wouldn't idle down under 1k rpm when it got warm. Still havn't checked plugs on the passenger side because I don't know how to get to them.
Last edited by tehcarguy; Jan 31, 2011 at 03:41 PM.
