Trouble shooting
Thread Starter
Pro
Joined: Nov 1999
Posts: 659
Likes: 0
From: Woodland Ca
Re: Trouble shooting (rick lambert)
I'm at 126k miles. At rebuild I replaced all sensors, plugs and wires, rotor cap.
I have had both the cat and pre-cat's checked...OK.
Most reciently, I replaced the ignition module.
How would I test the O2 sensor?
I have had both the cat and pre-cat's checked...OK.
Most reciently, I replaced the ignition module.
How would I test the O2 sensor?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
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
Drifting
Joined: May 1999
Posts: 1,478
Likes: 3
From: Sacramento, CA Money can't buy happiness - but it's more comfortable to cry in a Corvette than a Yugo.
Re: Trouble shooting (BIG K)
If the O2 sensor failed completely it would code, but if it is just weak it will return bad voltage values to the ECM which causes it to run lousy but not throw a code.
I did a major tune-up on my sister's 91 Caravan and in a few days it started to run worse than before the tune-up. Couldn't figure the problem out so she took it to the dealer who couldn't figure it out either. I started from scratch electrically checking every new ignition part I put on the van. The brand new #6 spark plug was going bad and failing to spark. Replaced the plug and the van has never run better. Absolutely no reason for the intermittant failure of a brand new plug that I know of. I didn't crack it putting it in; it was the easiest one of all to install and I use a torque wrench on every plug and bolt where possible.
Could be anything. Does it have a certain rpm or load or temp where it appears to be worse?
1) Have you tried putting an inductive timing light on each spark plug wire and watching to see if each is firing smoothly? Have you opened the hood in the dark while it is running and looked closely for "blue arcs" from the spark plug wires to ground or other wires?
2) Have you checked your major ground points?
3) When did dyou last replace the MAF Power and Burn-off relays?
4) Is the alternator putting 13 volts back into the system?
5) How old is the fuel pump and the in-line fuel filter?
6) What is your fuel pressure?
I did a major tune-up on my sister's 91 Caravan and in a few days it started to run worse than before the tune-up. Couldn't figure the problem out so she took it to the dealer who couldn't figure it out either. I started from scratch electrically checking every new ignition part I put on the van. The brand new #6 spark plug was going bad and failing to spark. Replaced the plug and the van has never run better. Absolutely no reason for the intermittant failure of a brand new plug that I know of. I didn't crack it putting it in; it was the easiest one of all to install and I use a torque wrench on every plug and bolt where possible.
Could be anything. Does it have a certain rpm or load or temp where it appears to be worse?
1) Have you tried putting an inductive timing light on each spark plug wire and watching to see if each is firing smoothly? Have you opened the hood in the dark while it is running and looked closely for "blue arcs" from the spark plug wires to ground or other wires?
2) Have you checked your major ground points?
3) When did dyou last replace the MAF Power and Burn-off relays?
4) Is the alternator putting 13 volts back into the system?
5) How old is the fuel pump and the in-line fuel filter?
6) What is your fuel pressure?
