Home
Don't have an account? Create one now! It's always free!


Forgot Password
Ed's Auto Parts - Mention MOTORGEN for a Discount!
Motorgen Sponsor: McLeod Racing
Motorgen Sponsor: American Muscle - Add style and performance to your Stang
Motorgen Sponsor: Hall Fabrication & Racing
Motorgen Sponsor: Injectors Plus - Performance Fuel Delivery Systems
Reply
 
Thread Tools
Old 04-04-2012, 01:19 AM   #1
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default The Tale of the Stumbling Vette

Well I've had this issue of the Vette not gettming more than half a mile or so before it would go into horrific lurches/stumbling. It's a Paul's (ls1z28's) house now and he's trying to figure out WTF is wrong. And it's a mystery so far.

Every electrical connection and relay has been checked. The harness has been inspected for any frayed wires. The alternator has been checked, the battery. the computer has been checked, including disassembly to check for cracked soldering. Nothing is wrong. We're down to two ideas, and if that doesn't solve it the one remaining is a real bitch assuming we haven't forgotten anything else.

So tomorrow, he'll be replacing the cam position sensor. It isn't throwing ANY codes, but it is possible to fail intermittently without throwing a code apparently. After that, we'll reflash the computer. The negative battery cable wasn't really well connected and showed signs of arching, *maybe* it corrupted some part of the flash with a surge; but that's a fairly wild hypothesis. So what are we left with then? Crank shaft end play, which can cause this kind of behavior. But that means removing the engine, etc. Not something I have money for now. So hopefully it's the cam position sensor.

The only thing we can say now is that it doesn't appear to be anything in the electrical system itself and seems to only happen when the computer goes into closed loop. If you fire it up and drive it immediately, it's ok for a minute or two.

On the upside, we discovered the MAF was dying, replaced that and now all the misses are gone. He's replaced the ignition switch, which was fried and was probably related to the poor starting situation. We're replacing the negative cable (already replaced the positive) just to make sure there's good current, useful thing to do anyway.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 04-04-2012, 01:42 AM   #2
Shaolin CraneShaolin Crane is offline
pain's fun, hit me again
 
Shaolin Crane's Avatar
 
Join Date: Sep 2009
Posts: 6,264
Default

I really doubt it's a camshaft issue, have you checked all things related to the fuel system?
__________________
Quote:
Originally Posted by Bruce Lee
Forget about winning and losing; forget about pride and pain. Let your opponent graze your skin and you smash into his flesh; let him smash into your flesh and you fracture his bones; let him fracture your bones and you take his life. Do not be concerned with escaping safely — lay your life before him

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Stopping the world!
  Reply With Quote
Old 04-04-2012, 02:08 AM   #3
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Quote:
Originally Posted by Shaolin Crane View Post
I really doubt it's a camshaft issue, have you checked all things related to the fuel system?
Pump and relays, yes. The filter regulator may be a little clogged, but that wouldn't explain this behavior.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 04-04-2012, 08:26 AM   #4
kdracer73kdracer73 is offline
Senior Member
 
kdracer73's Avatar
 
Join Date: Apr 2008
Posts: 1,557
Default

Does he have a scan tool that can do data logging? We need to see what data is changing/dropping out. How close is is the current location to Fullerton. I can bring a good scan tool Sat evening .
__________________
I drive a hybrid, It burns gas and rubber..
Alcohol Tobacco & Firearms should be a convenience store, not a government agency.
  Reply With Quote
Old 04-04-2012, 11:55 AM   #5
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Quote:
Originally Posted by kdracer73 View Post
Does he have a scan tool that can do data logging? We need to see what data is changing/dropping out. How close is is the current location to Fullerton. I can bring a good scan tool Sat evening .
He has the Tech II. Will that do it?
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 04-04-2012, 11:59 AM   #6
Shaolin CraneShaolin Crane is offline
pain's fun, hit me again
 
Shaolin Crane's Avatar
 
Join Date: Sep 2009
Posts: 6,264
Default

Yes
__________________
Quote:
Originally Posted by Bruce Lee
Forget about winning and losing; forget about pride and pain. Let your opponent graze your skin and you smash into his flesh; let him smash into your flesh and you fracture his bones; let him fracture your bones and you take his life. Do not be concerned with escaping safely — lay your life before him

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Stopping the world!
  Reply With Quote
Old 04-04-2012, 12:00 PM   #7
kdracer73kdracer73 is offline
Senior Member
 
kdracer73's Avatar
 
Join Date: Apr 2008
Posts: 1,557
Default

Quote:
Originally Posted by Vettezuki View Post
He has the Tech II. Will that do it?
Yes ! Probably better than mine. Tech II is the GM factory tool.
__________________
I drive a hybrid, It burns gas and rubber..
Alcohol Tobacco & Firearms should be a convenience store, not a government agency.
  Reply With Quote
Old 04-04-2012, 12:44 PM   #8
blackaxblackax is offline
Senior Member
 
blackax's Avatar
 
Join Date: Jan 2010
Posts: 1,255
Default

Quote:
Originally Posted by Vettezuki View Post
He has the Tech II. Will that do it?
A Tech II is the best tool for the job...

What is the fuel pressure?
__________________
2006 CTS-V
1993 Trooper
1991 Impulse RS
1988 Trooper II SAS
1986 TrooperII (No Rear)
1988 Impulse (dead)
1983 K20
  Reply With Quote
Old 04-04-2012, 01:47 PM   #9
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Quote:
Originally Posted by blackax View Post
A Tech II is the best tool for the job...

What is the fuel pressure?
Around 58 and stable.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Old 04-04-2012, 05:40 PM   #10
VettezukiVettezuki is offline
I, Vettezuki
 
Vettezuki's Avatar
 
Join Date: Feb 2006
Posts: 14,754
Default

Just got a text. Still driving him nuts. This is some crazy ass gremlin.
__________________
Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen on
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(active)
Motorgen Project Car
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
(back burner)
  Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -7. The time now is 10:28 PM.