HELP My Viper is Stalling when down shifting??????

[Da1cop]

When I’m down shifting and going into first the car stalls when the clutch is in. Does anyone know what my problem may be??? Thanks, Darrick

[hemibeep]

What year car?

If it is a new battery, the car needs time to learn..

Also may be throttle bodys out of synch,

Maybe a trouble code? engine light on?

[Da1cop]

1996 rt-10....engine light is not on(only when car stalls). Not a new battery!

[GR8_ASP]

Low battery voltage can do it. But, since you now state it as a Gen I the most common cause is poor throttle cable synchronization. Check the How To's (see menu above) for how to synch them.

[Jess 96RT]

Replace the battery.

[IL96RT10]

I am having the same problem now. It is not the batter just replaced it on saturday and car is having same problem. It stalls whenever I am at a stop light or sign and seems like it is just idling really really low and when I let out the clutch foot off the gas, car just dies. It starts right back up but stall when I am not moving. Any help would be great

[99 R/T 10]

This happened on my old 96 as well. Try disconnecting the batt.(or you can pull the three computer plugs to the PCM) to reset the computer. The problem went away, never to return.

[Joseph Dell]

I second the 'replace the battery'. if the battery is more than 18 months old, replace it.

[Steve 00RT/10]

I have a similar problem. Very strange. Started last spring about 50 miles after the SC add.

Pushing the clutch in at highways speeds--no problem--returns to normal idle--no dip.
Downshifting to 1st and coming to a stop causes the RPMs to dip to 400 or so and sometimes come back--sometimes stall. A slight blip anywhere in the slow down mode will immediately reset the idle to normal.

Totally disconnecting the battery (negative cable too) and PCM plugs will reset it and everything is normal for a few start cycles--then it goes back to dipping again. It's not really a big deal any more--be nice to fix it, but I've learned to live with it. I have the 96 PCM in my 2000 car.

To date--I have: Replaced the battery, replaced the O2s with Mopars (had new Bosch ones in there), stuck a smaller piece of tubing in the IAC motor hose to the air cleaner, took the IAC motor apart and totally cleaned it out.


Steve

[poweradded]

optima red top

[95Viper]

Da1cop and Steve, My 95 was doing the exact thing. While there are about 10 things that can cause this problem, please take 30 minutes and do this. It worked for me.

IAC on Pass side. 2 bolts to remove it, then 2 to break it in half. Take sensor safe cleaner and spray the heck out of it using a white cloth until it is all clean. I'm not sure what the electrical connection to the airbox is (by the IAC hose)but I unplugged it and removed the sensor in the airbox and wiped that with a dry cotton cloth.

Then remove intake hoses and prop open TB butterfly and spray all around there. Make sure ridges of carbon haven't built up not letting the TB snap shut. I even used a toothbrush to get around the edges. Toothbrush and flashlight until it was perfect.

Then resynch the cables following multiple previous posts. Works great!

[dblankenbaker]

If you JUST replaced the battery and have a VEC-1, and didn't zero out the VEC-1, your car will do this until the PCM has time to learn w/the VEC-1. After replacing/disconnecting the battery, you are supposed to zero out the VEC-1, drive the car, and slowly move the knobs to your settings while driving.

[Jack B]

The idle rpm and rpm upon de-acceleration are controlled by the ECU which in turn modifies a/f, timing and the idle air motor. With a heathy engine the issue has to be one of the following:

Idle air motor (stepper)
O2 sensor
ECU Error (which could be a faulty unit or issues created by low voltage or ground referening)

In most cases by viewing the fuel trim, stepper action and the O2 sensor voltage with a scanner you will find the problem.

[IL96RT10]

Thanks for all the help guys but I have changed the battery over the weekend and it still does it. I just wanted to avoid going to the dealership b/c the only one w/ an actual tech is like 60 miles away and didn't want to drive the car all that way if it might stall

[Steve 00RT/10]

Da1cop and Steve, My 95 was doing the exact thing. While there are about 10 things that can cause this problem, please take 30 minutes and do this. It worked for me.

Hi Craig,

I wish I could say I hadn't done what you mention, but I have. I cleaned the TBs good when I put the blower on. They were actually pretty clean for 55,000 miles. I completed disassembled the IAC motor and cleaned it up---no difference. Perhaps, as Jack suggests, the PCM may be bad. I have adequate voltage. Sean offered to swap his PCM out with mine for a test, but I chose not to thinking I would find a solution. Maybe I should have taken him up on his offer. I got used to it over 9,000 miles last summer. Ron at DSD says there's a way to fool the IAC motor, but it seems over my pay grade and tooling. Maybe I'll have him take a look next year when we're down some time.

Steve