Engine/Transmission (1994 - 1998) No power, low boost

[MHixson]

Hey guys, new to the board and enjoy reading all the great posts. My truck has lost power and I can't get much more than 12 or 15 lbs of boost. I have had the truck for 5 years and this truck has stunned many. I think it is mostly stock besides what is listed in my sig. It normally runs 28 - 30 lbs boost and has always ran great till the other day. I have checked all boots/hoses, had the turbo off and checked to see if the waste gate was stuck open. I checked the line from the manifold to the AFC and it is good. EGTs are 900 or so. Any more ideas on where to look? The truck has 150k miles on it. Thanks in advance for your help.

 

[BPonci]

Run a boost leak test. Other spots to check are the manifold gasket and check fuel pressure. A weak overflow valve can give you the same symtoms. Good Luck!

 

[Vaughn MacKenzie]

MHixson a friend had a similar problem. After trying a bunch of different stuff he found out his fuel solenoid wasn't opening all the way. It is at the back of the injection pump and down a ways and there is a rubber boot around it. Standing on the driver's side you can reach it pretty well.



Try turning the key on then go try pulling up on that, the boot covers the linkage, to make sure it clicks all the way up. Then drive it and see if your power came back.



Vaughn

 

[MHixson]

Thanks guys,

I checked the fuel solenoid, it was opening all the way though. I have new boots coming in tomorrow so I will pressure check everything after I get them on. I also checked my overflow spring, it was shorter than . 500 and after stretching it a bit the trucks power is coming back at low RPM (2nd and 3rd gear) and falls away at about 10 lbs boost or around 1800 RPM.



Thanks for all your ideas, does seem to be fuel pressure related. Will replacing the overflow valve cure it? Where can I get a replacement valve?



Thanks again

 

[RGuzzo]

It did for me. Contact marty tompkins517 6941522 42. 50 for valve and 2gaskets

 

[RGuzzo]

check your fuel heater remove the element. put it together and test 4 a leak possibly in the elec. conn. check all fuel lines and conn. this is a messy time consuming job