Cold Engine from spark plugs????

[Cal Cobra]

My Viper used to run like a top, didn't have to warm up, no bucking (after adjusting the throttle bodies), basically it drove like a new car.

I've noticed over the past couple of months (since adding headers, B&B exhaust and cat delete, as well as new SRT Viper plugs), that it now acts like it has to warm up like an old car with a manual choke. Until it warms up, it idles a little rough, and if you don't gas it a little here and there it wants to die. Once it warms up, it runs fine.

I'm wondering if it couldn't be due to using the new SRT Viper plugs vs the original plugs?

Any ideas??

TIA
Cal

 

[ArlyDude]

Mine is horrible on a cold start. I get idle hang as well until she warms up. 97GTS she is.

 

[cyaford]

I just switched from the stock plugs to the SRT-10 plugs. No issues whatsoever.......yet.

 

[Viper Wizard]

I've noticed over the past couple of months (since adding headers, B&B exhaust and cat delete, as well as new SRT Viper plugs), that it now acts like it has to warm up like an old car with a manual choke. Any ideas??

Get use to your new animal or go back to stock!

 

[Schulmann]

With all these mods your car runs likely lean at startup (above 15AFR) this is why you have the hesitation. I think it is a weakness in the 96 PCM. I have the same problem ...

 

[Cal Cobra]

Schulmann once your Viper warms up, it's fine?

cyaford is your Viper stock?

Viper Wizard... If this is the way it is, I'm ok with it, I just want to make sure it's not the plugs or something else easy to remedy. Go back to stock....hmm...nah that's OK, I like the Le Mans sound

Thanks!
Cal

 

[cyaford]

Cal: I just have an exhaust for now. I'll be adding tubes/filters and cat delete soon. I'll report back if there are any issues like you are experiencing.

 

[Schulmann]

Cal Cobra,

Yes my Viper is rough when cold. But after 5 min it gets better. If I add more fuel at the startup it runs perfectly. You should stay with the stock plugs they are the best for your car.

Another thing. If you disconnect your PCM your viper will be harder to start in cold weather. Once you drive 50-100 miles it gets its fuel mapp updated and runs better.

 

[Cal Cobra]

Thanks Schulmann, sounds the same here. I don't disconnect the PCM (it was reset when we did the upgrades as the battery was disconnected), but I drive mine enough not to worry about the battery drain syndrom.

I'm considering trying the stock plugs for kicks just to see if there's any difference. The plugs I'm running now are the same as the Gen3 Vipers, which some people swear by. I wonder if the cat delete is letting it run too lean initially? Maybe I should throw some hi-flo cats on.

I'm assuming that your Viper isn't stock?

Thanks,
Cal

 

[Schulmann]

Just remove your cats and stay like that until your next smog check. I can put back my cats in an hour ...

If you reset your PCM that explains also some of the troubles. I have a 96 PCM and my viper starts like yours.

I just noticed that you have an aluminum fly wheel. That can cause also some troubles ...

What are the numbers on the plugs that you use in your Viper ?

I presume you have cat sims, am I right ?

Your next upgrade should be a VEC2 with two LC-1 unit connected to.

By the way we have the similar mods, except that my Viper is supercharged.

 

[JiPi]

Schulmann,
Why/how can an aluminum flywheel cause troubles?