I'm having trouble with a reman vp44 I just installed. Since it was first run it keeps throwing a P1688 code. I have put about 10 miles on it and it is running great with no perceivable problems. I clear the code and on the second restart it comes back. My scanner shows a hard P1688 and a pending P1688 with no other codes. My scanner is an Innova 3130 capable of pulling Chrysler Enhanced codes and still pulls no other codes.

the VP44 I removed would occasionally throw a P0216 code or P1689 but for the most part it was hard starting, especially when hot. It never threw a P1688.

The company I got it from is one of the larger suppliers with a very good reputation. They have never heard of this problem and are looking into it.

So far I have tried disconnecting the batteries and letting it sit overnight, unplugging the VP44 with key off and unplugging it with key on. When I unplugged the VP44 with key on it threw a no communication code and once cleared it took awhile for the P1688 to throw again.

Anyone ever experienced this or have anything else to try?

Also for got to mention I have a Fass DRP pump and about 14psi at idle and 9 psi WOT.

 

P1688 "Internal Fuel Injection Pump Controller Failure"

Sounds like a bad VP

 

Thanks for the reply. The company I bought it from is being a pain with the tech support. It took me a week to get them to acknowledge the problem and hopefully they are handling it today.

 

What company?

 

Thoroughbred. I finally got a RMA number to send it back but that means the truck will be down for weeks. Im not too happy about that!