Adjusting Idle Speed on Gen1 with VEC-3

[TexasPettey]

Anyone have a way to easily adjust the idle speed up/down on a Gen1 with a VEC-3? I can work the adjuster screws on the Accufab throttle bodies, but it's a real pain.

I'm trying to get my idle speed up so that I can pass idle emissions with my new CAM. It won't pass HC at 750 RPM idle, but does OK at higher RPM. I'd like to set it for around 1100 RPM and see how it does.

 

[uvbnbit]

I would think that would be the only way to do it. Would PCM have to be reset afterwards?

 

[plumcrazy]

I didnt think the vec could do that

 

[uvbnbit]

I didnt think the vec could do that

It can't. I was referring to the adjusting the TB's. (if you were responding to my reply)

 

[GTS Dean]

I think you'll need to reflash the PCM to raise the idle speed since it's controlled by the IAC motor. Call Weaver.

 

[Jack B]

The PCM controls the IAC and the timing to control the idle. It is doubtful the throttle bodies will work, you would be fighting the pcm and eventually could set a code.

A viper should idle at 670-680. The next tick up is 750. I used SCT to set my idle at 750.

 

[TexasPettey]

Thanks, guys. I know the TB screws work only by accident. When I first installed my Accufabs, the screws were subject to movement from the vibration. They would slowly work their way in and increase the idle speed. It was a really interesting debug experience. I couldn't figure out why my idle speed kept slowly climbing up over a couple of weeks. I ended up putting locktite on the threads to fix it.

I'll have to see if messing with the TB screws is worth it for emissions testing. It was not easy to try to set a specific idle speed with the TB screws. I can get a low mileage waiver for <7500 miles/year. However, they make it a real pain.

 

[got one]

Thanks, guys. I know the TB screws work only by accident. When I first installed my Accufabs, the screws were subject to movement from the vibration. They would slowly work their way in and increase the idle speed. It was a really interesting debug experience. I couldn't figure out why my idle speed kept slowly climbing up over a couple of weeks. I ended up putting locktite on the threads to fix it.

I'll have to see if messing with the TB screws is worth it for emissions testing. It was not easy to try to set a specific idle speed with the TB screws. I can get a low mileage waiver for <7500 miles/year. However, they make it a real pain.

Get it inspected in Mexico... Maybe I can help