The engine went dead like I turned the ignition off. It would turn over and the first time I hit the ignition switch the fuel pressure did not move off zero so I thought for one thing I had lost the lift pump (Carter).

Then I tried it again. Turned the switch on and then off. The pressure ran up to 17 plus or about 1.5 pounds higher than it normally runs while at idle.

I ran the codes and all it came up with was a P1693 which I thought was a message that my VP44 had quit. Upon returning home I reviewed the code list and found that my P1693 says its a "Generic fault indicating a fault in the bus or PCM/ECM interface".

Anybody have any ideas what I am looking at. It happened 100 miles from home and I left it at a business, thinking I would just order a new IP but now I don't know if I have a PCM/ECM failure or maybe even a connector lost contact.

Any ideas would be appreciated. Thanks in advance.

 

99% that your VP has failed electronically. When the VP fails electronically, it will do exactly what you said, which is shut off like you turned it off, and it may throw the P1693 code. Just to be sure, check the fuel system fuses/relays. You could even have someone hook up to it with a scanner to see if there's any other codes you haven't seen.

 

Thanks. You are right. It had the P1688 which meant that the companion computer was done.

 

Don't install a VP unless you are certain. Look up 1693. It is a companion code and is not a specific indication of problems with the VP. You need more information. Start by scanning your truck with a scanner.

People on the forums who have no dollars at risk say "more than likely it is the VP." Unknowing owners buy and install more VP than are necessary. Don't make that mistake as it won't help with anything other than making your wallet lighter.

 

Very good advice but I'd never tell someone that I thought their VP was done for if I definitely didn't think it was. If you've read any of my other posts, while trying to help others, I always look for any other possible problem so as not to have someone throw away $1500. The OP described a typical scenario when a VP computer has shorted out from deteriorated lead free solder. Sometimes the VP's can give a few signs and sometimes not. Also, the OP's situation is similar to how my VP left me stranded on the side of the road too. I myself didn't think it was the VP either but after talking to Chip at Bluechipdiesel, he said thats what it was and to prove he was right, he offered to send me a VP (paid for first of course), and if the truck didn't start after installing it then he'd take it back no questions asked. That was a deal I couldn't pass up since I had no other options left as all others possibles had been exhausted. Oh, by the way, the truck did start up too.

 

First, dont listen to a lot of these guys - you cannot depend on the key on/off trick to extract the codes. You need a scanner at your disposal.

Second, P1693 is the companion code telling you have another code. P1688 is one of the two death codes for the VP-44 (P0216 being the other). If the truck doesnt start, doesnt stay running, is experiencing power loss, or is experiencing any sort of dead pedal - then you need new VP-44.

 

you forgot p1689