Loss of power and a lope...

J.Warning · Dec 3, 2011

I started my truck and it had a hard idle like almost a lope tune(i dont have a lope tune) and when i was driving it would shake then when i let off it would stop but then soon as i give it gas it would start again and service engine lights on i went about a mile and it stopped this is the 2 time its happen has a loss in power too

B.Warning · Dec 3, 2011

Also...He's running a Bully Dog watch dog for a gauge and scan tool. The check engine light is on but the bully dog shows that it has 0 codes.

Big Bore · Dec 3, 2011

Try scanning with something else. But, sounds like VCH, UVCH to me, very common problem that exhibits those same symptoms.

Does that Bully Dog read fuel pressure?

B.Warning · Dec 3, 2011

Excuse my ignorance but what is VCH, UVCH. I'm not at all familiar with 7.3. The op is my little brother. I'm not sure if the Bully Dog reads fp or not, I don't believe it does.

Big Bore · Dec 3, 2011

VCH = Valve Cover Harness

UVCH = Under Valve Cover Harness

The valve cover gasket has a connector for the injector and glow plug harness. One connector on the outside to the main harness, and one inside that connects to the injector and glow plug harness. The UVCH will vibrate loose. Ford has a repair clip both sides of the connector. Make sure you get the one for under the VC, they will often give you the external repair clip. Check for loose connections at all points on the harness and make sure that TS chip is plugged in good, or pull it and see if it starts then (REMOVE KEYS FROM IGNITION, NOT JUST IN OFF POSITION!!!). If that Bully Dog plugs into the data port, unplug it, sounds like it's useless anyway.

It would be a good idea to find someone with a real scan tool. If the SES light is thrown it should be logging a code. Otherwise we are all just shooting in the dark as it could be several problems and it will just frustrate everyone.

Tom S · Dec 3, 2011

Big Bore said:
Try scanning with something else. But, sounds like VCH, UVCH to me, very common problem that exhibits those same symptoms.

Does that Bully Dog read fuel pressure?

Did you mean HPOP?

Big Bore · Dec 3, 2011

Tom S said:
Did you mean HPOP?

Huh uh, I actually meant fuel pressure, lol. I dont know anything about that Bully Dog.

HPO pressure is another possibilty, which is why I suggested getting a real code reader, since obviously that Bully Dog isnt reading properly since he has a light but no codes. He could have an IPR or ICP problem.

DcMoore · Dec 3, 2011

Check the nut on the back of the IPR (Injection Pressure Regulator) also.. It might also be dirty.. It's located on the drivers side underneath the HPOP.