So the problem is I have my RPM readout from my AVCR and RSM going blank and popping back up intermitantly as im driving down the road. Usually as im hitting a bump on the highway or something. So besides a loose connection what other problems would cause this? Also it has disappeared before and as i came to a stop the idle would bounce up and down between 1100 and 600 or so. And when it came back on the idle leveled out. So im thinking the PFC is not getting a good read but why? Thanks in advance for any help or thoughts.

 

who installed the AVCR? How was it tapped into the rpm signal?

 

Don't know to be honest. It's been on the car for years and the engine was just rebuilt and put back in from the guys in Garland, TX. I shot them an email yesterday to see if they knew so we shall see.

 

Ok so now my AVCR rpm read doesn't go blank just the RSM. However the rpms on my AVCR bounce around under throttle. They will hit around 9000 and drop back down to what everything else is reading it correctly at. They however do not disappear from my power fc. So im thinking the connection is bad to obvioiusly the RSM and AVCR only. Under wot my rpms also disappear every time from the RSM and bounce around on the AVCR. Doesn't matter what gear. Any thoughts

 

you're going to have to go back through the wiring. If vampire taps were used then they could be coming loose

 

I will check the wiring of course to make sure nothing is loose. Could this also be ignition related in any way?

 

Sounds like a bad ground.

 

Update: It turned out to be a hot wire that was touching part of the block and had melted through causing some serious arching. Found out as I almost shocked the hell out of myself