On the truck in my sig (161k miles), it started cutting out, going to idle, no throttle response etc a few months ago. I thought great, either the VP44 is going or the APPS is bad. I just happened to start playing with the Edge Juice and set one of the displays to MPH. The speed display was jumping from 0 mph to 164 mph and everywhere in between, and it was cutting out any time the speed was over 115mph. I pulled over and unplugged the speed sensor, and it runs perfect. I put in a new one from Dodge and it worked fine for about a month and then it started again. Sometimes it will run fine for 2-300 miles then act up for 15-20 miles and go back to working again, then be really erratic. I tried cleaning the plug with contact cleaner, then it worked fine for a day then cut out the next. I cleaned it with contact cleaner again and filled it with dielectric grease and it worked fine for a day then started cutting again today. I unplugged it and drove 200 miles today with no problems. Every time the truck cuts out the speedo on the edge is reading all over the place, when it is running fine it sits right at my actual speed. The factory speedo reads dead on even if the engine is cutting out and I dont have a check engine light, or any codes last time I checked. Any ideas?

 

I am having a similar problem but it is with my tach. Truck will run fine for 200-2000 miles, then the tach will go all over the place and truck will hesitate. I can not reproduce the problem but I know when my tach is acting up the truck is getting ready to surge. I too though VP or APPS. I have codes though, typically 1693, 1694, and 1698. I had 500 (Speed Sensor) but I changed the sensor and I no longer get the code. I have determined it is an electrical problem, probably somewhere between my ECU and PCU. I plan to play with the plugs and grounds this week.

 

I had similar tach problems with another truck, replaced the tach sensor behind the vp (dont know if you can get to it with the vp in place) and had no more isssues.