Help with troubleshooting.
Thread Starter
5th Gear
Joined: Jan 2014
Posts: 5
Likes: 0
From: Stockholm
Help with troubleshooting.
Hi!
I am new at the forum and is looking for some tips =)
I have got a few (minor?) problems with my c4 vette (88),
Prob1: It drives rough at low rpm's and when you floor it, it judders before taking of. I was thinking i might be the fuel injectors?
Prob2: When revving the engine, toe and heal driving etc it makes a high pitched sound (only for a second).
Prob3: If i leave the battery in the car for about a week it will be flat, if I disconnect the battery its fine.
Any ideas?
(I apologize if there is allot of spelling and grammar mistakes)
I am new at the forum and is looking for some tips =)
I have got a few (minor?) problems with my c4 vette (88),
Prob1: It drives rough at low rpm's and when you floor it, it judders before taking of. I was thinking i might be the fuel injectors?
Prob2: When revving the engine, toe and heal driving etc it makes a high pitched sound (only for a second).
Prob3: If i leave the battery in the car for about a week it will be flat, if I disconnect the battery its fine.
Any ideas?
(I apologize if there is allot of spelling and grammar mistakes)
Safety Car
Joined: Aug 2013
Posts: 4,424
Likes: 603
From: Minneapolis Mn
Issues
I'm no expert but these are the steps I'd start out with:
1) try some chemical cleaner like Seafoam or other product you add to the gas and see if that helps. Also check that no wiring is loose.
2) Sounds like that might be the serpentine belt, check it out.
3) Try disconnecting the battery for the same length of time and see if it dies. If it doesn't, connect a meter between the cable and battery and disconnect each fuse till you find where the draw is, that's the circuit to check out.
1) try some chemical cleaner like Seafoam or other product you add to the gas and see if that helps. Also check that no wiring is loose.
2) Sounds like that might be the serpentine belt, check it out.
3) Try disconnecting the battery for the same length of time and see if it dies. If it doesn't, connect a meter between the cable and battery and disconnect each fuse till you find where the draw is, that's the circuit to check out.
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
Start by pulling the engine fault codes and see if anything showing
http://www.corvettephotographs.com/c4vettes/codes.htm
report back what you find
http://www.corvettephotographs.com/c4vettes/codes.htm
report back what you find
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
There are lots of sneaky ways for the air to get in, like an EGR valve that is stuck open. Dried out and cracked rubber vacuum lines. Broken vacuum check valve. The little plastic vacuum lines can touch something hot and melt.
Thread Starter
5th Gear
Joined: Jan 2014
Posts: 5
Likes: 0
From: Stockholm
error codes
Start by pulling the engine fault codes and see if anything showing
http://www.corvettephotographs.com/c4vettes/codes.htm
report back what you find
http://www.corvettephotographs.com/c4vettes/codes.htm
report back what you find
(flash,flash,flash,flash,flash (pause) flash,flash,flash,flash) times 3.
followed by code 12 times 3 and then the same sequence repeated over and over again. I have no idea what this means and i can find nothing on the internet, any idea? (do you think I have to take the codes again)
/Micke
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Three "12"s followed by three more "12"s means there are no stored trouble codes.
Regarding Problem 1:
Check manifold pressure (vacuum) for any vacuum leaks.
Check fuel pressure, with vacuum line disconnected and plugged. It should hold steady if you blip the accelerator.
Check for a bad spark plug/wire.
Verify base timing is between 6-8 deg BTDC, with connector open in the Blk/Tan wire near the brake booster.
Regarding Problem 1:
Check manifold pressure (vacuum) for any vacuum leaks.
Check fuel pressure, with vacuum line disconnected and plugged. It should hold steady if you blip the accelerator.
Check for a bad spark plug/wire.
Verify base timing is between 6-8 deg BTDC, with connector open in the Blk/Tan wire near the brake booster.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
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
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Race Director
Joined: Aug 2007
Posts: 11,889
Likes: 8
From: Whitefish Falls Ontario
St. Jude Donor '08-'09
For the battery, disconnect the negative cable and connect a meter set to amps scale with one lead to the battery and the other to the cable. You are looking for a reading of less than .05 amps. If you get higher you need to start pulling fuses as suggested earlier to find which circuit is giving you the problem. When you have the door open to check fuses you will need to fix the door switch for the lights and wait for them to time out before you start..
