Hi i have a 1995 PSD with an auto tranny . When truck is cold the tranny seem's almost like its slipping ,then it well pull for a few seconds then seems to slip again and there is a hissing noise coming from the tranny area .I took it to a mechanic and he thinks the trannys fine and that were is a problem with the wastegate ,he said it feels like the trucks getting no boost . Makes sence that would be why it seem's to be slipping the trucks haveing a hard time to move cause there no power . Ps i also made a similar problem in the summer (same without the hissing noise) and i had a scanner put on the truck and it came up with the code PO476 exhaust back pressure control vaule performance malfuncation. The back pressure cantrol vaule is the wastegate right ?
thank for any imput ...!!!

 

It is the Exhuast backpressure valve that is closed giving you this problem. No the wastegate and EBPV aren't the same though. The 94.5 to 97 powerstrokes didn't come with a wastegate. You probably have a bad exhaust backpressue sensor or the tube going to it is clogged. Either was if it were mine I would just unplug the valve and be done with it. The connector is located almost right under the air filter intake tubing where it goes into the turbo. It will be a plastic connector with 2 wires coming form each end.

The first time I pressure washed my engine the valve closed and I had no idea what was going on. I thought it was also the transmission or the fan clutch lock right up but then it dried out and stopped jsut down the road. But then I put 4 inch straightpipe exhuast on and it sound like a 747 on take off with the valve closed so I unplugged it. I suggest you do the same.

 

Thanks i'll try that .. what do i do with the wire ?

 

I just left it lay there. With the connector there it can;t ground out and there is nothing hot enough there to hurt it. you could sip ties the wiring harness side to the main harness if you want to.