Well, went to dealer today and they replaced lift pump. FP increased to 15psi idle, 12psi cruising. Took on Hwy same surging problem occurring after 110KM per hour still. Took it back to dealer, now they are talking about replacing injector pump. I explained to the mechanic about the info I gathered from you guys regarding the possibility of the APPS being funky, He told me that it is a restricted item???? What is that supposed to mean? I told him yesterday I was driving on Hwy at 110km on cruise to make sure it was still doing it before I took it in, I turned off cruise and Pushed the pedal and there was absolutly no response. Almost like the engine was powerless I pulled over and started going again and everything was fine???? I'm at a loss. I don't believe that the Injector pump is the problem if I'm getting the pressure readings that I'm getting. The problem only occurs under high speed(load). He did a computer check and it showed no faults. He did say that when he checked it last week there was an error reading fuel timing fault,but it's not there now. I wonder if it erased when I tried the APPS reset procedure that someone posted???Any help on this would be greatly appreciated

 

Sounds to me like your injection pump (VP44). If it was your APPS, you would have the problem at all speeds, even when pushing the pedal down in neutral. I believe its your VP44 not being able to keep up with engine demand for fuel. The VP44 has been known to give problems like this. Even if it has good pressure going to it.

Good luck to you. Hope you get it fixed soon.

 

Thanks, That makes sense to me now, I just talked to the dealer and they have ordered a new pump should be in next week.

 

Glad to help. Good to hear that it's gettin fixed soon to.