Help with sick Snake

[1 Bad Snake]

I am having a very peculiar problem, at different speeds and RPM's, in different gears, I experience a strong jerking (almost like the car is missing)motion. The problem only occurs once the car has warmed up a litte, and not always at the same temp. This problem causes my RPM's to drop almost to stall and then dart up suddenly, then will drive okay for a couple of minutes and repeat. The check engine light will also come on. The problem has baffled an excellent Viper tech and Viper racing team Crew chief. I have replaced plugs, plug wires, Fuel filter, Coil, retuned engine and throttle bodies, replaced fuel injection wiring harness and pcm, O2 sensors, and added hi flow cats. The engine was rebuilt by Arrow less than two years ago, and has less than 4k since rebuild. The car did run for about a year without cats, computer and o2 sensors were replaced when HI flows were installed. All of this has been done over the last 6 weeks, Has anyone had or heard of a similar problem that can offer an avenue to pursue.

 

[JonB]

I have sent folks looking at this before, w/ success:

I would investigate the engine grounding strap.

When the motor was re-installed, I bet it was not tightened enuf.....or the contacts had gotten dirty and corrosion has developed. Or something else related to GROUND WIRE on that car.


TOO BAD THERE IS STILL NOT A PROBLEM-DIAGNOSIS AREA ON THIS SITE!

As even titled: " Been There....Fixed That! " Lotts aguys have posted obscure fixes......that SEARCH cannot later find.

 

[99 R/T 10]

Hey Jon,
Where is this grounding strap exactly?

Mike

 

[Doug Supercharged Vipers]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by wilddude:
Where is this grounding strap exactly?

<HR></BLOCKQUOTE>I don't think Jon would mind my jumping in ....

The ground strap is located on the right front side of the engine, just before the front crossmember.

- Have you tried watching the fuel pressure to see if it spikes?
- I would also assume you've had a DRB on it. What code came up with the MIL on?
- Also, have you checked the main harness where it plugs into the right side toe box?
- Have you checked the cam sensor?
- What about the crank sensor?
- Map sensor?
- TPS sensor?
- The main harness by itself?

Just thought I'd throw in a few more for you, good luck!

Doug Levin

 

[JonB]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Doug Supercharged Vipers:

Originally posted by wilddude:
Where is this grounding strap exactly?

<HR></BLOCKQUOTE>I don't think Jon would mind my jumping in ....

The ground strap is located on the right front side of the engine, just before the front crossmember.

- Have you checked the cam sensor?
- What about the crank sensor?
- - The main harness by itself?
Doug Levin

Moire good stuff from Doug. You gotta LOVE this site