okay this is really weird!! Need some diagnosis from experts

[Qualitywires.com]

I was driving my viper on the hwy. I had the rpms around 3k and slowly climbing. All of a sudden my car jerks for a tad second and I catch the tach drop down to zero! (Like the car stalled). The car quickly regained back to the 3k range on the tach. I think it did it because I was moving at about 60mph and it self jump started. So basically my car just died. This has happened in the past before.

This is what I have for Mods.
no cats
2 O2 SIMMS
3" Hennesssey Exhuast system
smooth tubes
K&N
and some other non-engine related items.

Why is my car doing this? Something computer related do you think? It's not giving off any check engine lights when it happens and at idle, it seems to do fine. My Viper is still under warranty but I don't want the Viper tech here to play trouble shoot on my Viper at my expense. (Joy rides, grease or whatever else that the dealership has a knack to break while in the shop).

thanks

 

[1TONY1]

One thing I would do is add the ground wires that Sean Roe recommends for the Roe s/c guys. It may not help, but it is free and you never know.

 

[Russ M]

Ab,

You were in gear and you saw the rpm drop from 3000-0? Or were you in neutral?

If you were in gear even if the car died it would still need to coast down from 3k to 0 to make that happen.

Assuming that you were in gear I would say its definatly a ground wire comming loose. Perhaps the one on the battery, I am not sure how the Viper tach gets its ground so you should start with that.

 

[1TONY1]

If the tach is electric and the engine died it would drop to zero rpm even if the engine was still turning.

 

[Qualitywires.com]

Where do I look for a ground? My car was idling funny one day and kept on stalling. I disconnected the battery and reset the computer and it seemed to reprogram itself fine. Then this happened. Yes I was in 4th gear when the engine or tach shut down. I pretty sure the engine shut down cause I felt a **** for a moment and then it restarted because the car was rolling in gear. Where do I look for this ground and sean roe's ground?? What are you talking about??

Thanks!

 

[Qualitywires.com]

Could it be the crank sensor?

 

[plumcrazy]

thats exaclty what my ram truck did when the crank sensor was bad. it eventually happened more and more often.

but mine would happen when I just got off the highway after turning maybe 3000RPM's and when i was coasting down to about 2000RPM's.

 

[Qualitywires.com]

BINGO!!! YEs!! That is exactly what happens to me!!

 

[RavenFan_94]

Digging up an old thread here. I just had my tranny replaced and on the way home this exact thing happened to me. Any updates as to the cause of this?

My vipertech is over an hour away for me, so any help would be appreciated.

 

[RavenFan_94]

Update. I just took the car around the block and the check engine light is on. I cycled it, but it is blinking and blinking. The pattern is 1, 2, long pause 1 and then 5 to 7 quick blinks (number is different almost everytime). I have the service manual but the code doesn't correspond.

Could this be caused by bad fuel? Out of necessity, I stopped at a Generic Gas station on the way home to fill up.

Also the head gaskets were just changed in the less 200 miles.

 

[MES]

No expert but the bolt where the red battery cable under the hood connects was loose causing the exact same thing. The nut on the outside was tight but there is another nut under the black plastic fuse block which supplies the power to the rest of the car. You have to remove the fuse block and twist it sideways to access it. Took me about a year to figure that one out.

 

[txlen]

sounds to me like a cranks sensor is fixing to take a dump on you....Len

 

[long Island snake man]

I have a 97 gts and i have a similar problem,when i brake or downshift say from 40 down to idle,my car stalls or the idle drops real low to about 100 rpms.My son was playing in the car and left the dome light on,i found it 3 days later,the battery is new so it started after 2 trys.

 

[DChan415]

I'd check all battery connections first. Wire wheel all connections at the battery, starter, + terminal, and all grounds.

 

[RavenFan_94]

Check the battery. Nada. Back to the dealer it goes.


Arrrrgh. Thanks for your help guys.

 

[Qualitywires.com]

It was the crank sensor. I think this is funny how this old post came up.

Crank sensor is not that expensive and can be installed in a snap!

It cured the problem and no more rpm and car dying problems.

 

[RavenFan_94]

Well you guys are right. It is either the crank or the cam sensor. Dealer can's isolate so needs to replace both. $450 to do the job. Ridiculous...

 

[Qualitywires.com]

They are ripping you off big time! You could replace both in less than 45 minutes easily.

 

[RavenFan_94]

I agree. I spoke with my Viper Tech and The Wizard and they laughed at the price the Annapolis dealer is charging. If the car were drivable, I'd have it out of there.

The Viper tax lives on.

 

[Qualitywires.com]

Are you mecahnically inclined? If so I will get you directions on what to do.

 

[RavenFan_94]

Reasonably. Thanks in advance for the help.