loss of power after miss-shift

[new york city viper]

last week i miss-shifted from 3rd to 2nd gear while driving at 75mph. Engine screamed , i can still shift in all gears smoothly but i cant go past 40mph on 1st , cant go past 60 on 2nd , deffintly lost alot of power, no leaks under car , no signs of breakage anywhere. Any one have any idea what i damaged?

 

[Fatboy 18]

What Gen Viper are we talking about here?

 

[new york city viper]

fatboy18- its a GEN 3- 2005 convertable

 

[Steve-Indy]

Valves, rocker arm (s)???

"Truck to Chuck"

 

[aries]

I'm gonna go with a bent valve or broken rocker arm. Stop driving it immediatley and take it in to be looked at.

 

[RTTTTed]

If you're a do-it-yourselfer pull the sparkplugs and do a compression test. Any different colors on the plug tips?

Is it running on all cylinders or missing on some?

Ted

 

[slysnake]

Isn't the Rev limiter supose to shut down the engine or something?

 

[BlackSnake99]

Isn't the Rev limiter supose to shut down the engine or something?

On the way up the rpm range the computer can cut the fun at redline and save the motor. On a downshift, the mechanical speed of the wheels determines the engine rpm speed, and electronics can't stop it. You can therefore overrev on downshifting and bent valves.

 

[RTTTTed]

"... i miss-shifted from 3rd to 2nd gear while driving at 75mph."

he wrote

 

[dave6666]

plum......... speak............

 

[bigmack339]

Mine was clutch only. Same problem after missed shift sir.

 

[dave6666]

Mine was clutch only. Same problem after missed shift sir.

The average car guy would be able to detect that smell.

plum............ speak............

 

[paxtu22]

Sounds like a bent valve. Is it possiable to over rev it @75mph in second gear? I think that my car is good for 80+ in second.

Eric

 

[CitySnake]

Overheated/melted cats.

 

[Martin]

Overheated/melted cats.

That would be a guess of mine, too. If you shock-loaded the engine by mis-shifting from 3rd to 2nd at speed, you may have floated valves and/or bent pushrods (or broken springs and/or rockers). Bent pushrods aren't a big deal as long as the bending didn't happen because the valves impacted the cylinders... If the valves impacted the cylinders, you've got bent valves for sure, and you'll either be hearing backfiring through the intake, or you'll be dumping gas straight out the exhaust valves and into the cats. If you're dumping gas into the cats, they will overheat quick and plug up.

In any event, you need to tow it into a shop pronto. If you do your own work, you should start by pulling the valve covers and looking at all the pushrods. If you see a bent one (or two or three), they're pretty easy to swap out. Once you get them swapped out (or determined that none are bent), do a compression check (and look at all the plugs to see if any of them are looking fouled or burnt). If compression is bad on any cylinder, it's head-work time.

 

[Viper Wizard]

The Viper is with me and the cats are the problem! Valve train is fine!!

 

[eucharistos]

kool

time for hiflows

 

[eucharistos]

Sounds like a bent valve. Is it possiable to over rev it @75mph in second gear? I think that my car is good for 80+ in second.

Eric

good point

 

[CitySnake]

kool

time for hiflows

Exactly! Should have been done already.

Good news considering the possibilities.

 

[VIPER BAZ UK]

Mr City did you have inside information here?????????

 

[dave6666]

The Viper is with me and the cats are the problem! Valve train is fine!!

Curious how does a missed shift affect the cats in such a manner that they no longer let the car run correctly? Said missed shift being within reason an instantaneous event. Cats are usually affected over time.

 

[99 R/T 10]

Valve floats, puts lots of unburned fuel into the exhaust, maybe?

 

[dave6666]

Valve floats, puts lots of unburned fuel into the exhaust, maybe?

But like I said in my question, that would be but a few seconds. I thought the cats were more robust - durable - than that.

 

[CitySnake]

Mr City did you have inside information here?????????

The posts are too close together, ehh???

 

[gb66gth]

...sounds like someone dodged a bullett!
I'm happy for you.

 

[Viper Wizard]

But like I said in my question, that would be but a few seconds. I thought the cats were more robust - durable - than that.

We've had a lot of issues with the stock ones. It looks like someone hit the honeycomb with a hammer. They may have been on there way out and this just finished them off. Hi-flows on order.

 

[04MambaNYC]

Hey Chuck, quick question - is this a silver Viper?

 

[Viper Wizard]

Hey Chuck, quick question - is this a silver Viper?

Slow yellow.

 

[Ratical2]

Slow yellow.

Thanks for the laugh, Chuck!

 

[kcobean]

Slow yellow.

You know I like ya Chuck, but posts like this make me question your competency in the Viper world.