Engine/Transmission (1994 - 1998) lost 1/2 my boost, could it be fuel filter?

[Gifford]

I recently lost half the boost I used to make (measured via westach boost/egr combo guage) It used to be able to get to 35 psi, now I'm lucky to make 17. Could a plugged fuel filter do this? (I havent changed it in a year (mebbe more).



Also recently lost all vacuum actuated accessories (cruise, A/c,4wd) does the wastegate operate off of vacuum on a 97 12 valve??

 

[TravisG]

I don't think it would be the fuel filter. You probably have a boost leak somewhere. Or a line from the vaccum pump is off. I know that 4wd is run off of vaccum, and I believe so is the cruise. You might check those lines and tighten up all your boots on the intercooler and intake. Good Luck. I am sure someone w/ a whole lot more knowledge than me will chime in here.

 

[markdixon]

Also check the fuel shut off solenoid Ive seen the rod inside rust and break and the boot will pull the fuel lever partly open. The truck will run but not have much power or smoke.

 

[DavidGardner]

Check all the big hoses (ducts) from the turbo to the intake system. Loose clamps, or holes in the hoses cause loss of boost. Has happened to me twice now. Usualy when pulling a grade. Both times the hose clamp was too loose and alowed the hose to blow off. This was accompanied by a loud roaring sound -loss of power and an imediate rise in egts. I know even a small hole or leak can cause what you are talking about. Good luck and let us know what you find the problem to be.

 

[DOWG]

I lost my boost in the manner you spoke of; changed the fuel filter and the boost was back immediately. I always carry a spare fuel filter, gallon jug of diesel and changed it on the side of the road.



Air + Fuel = Power



That may or may not be the problem, but it is an easy way to eliminate the fuel filter as a factor. I change my fuel filter every 10,000 miles; 2500 miles on the filter when I lost the boost.

 

[BPonci]

Are your pyro temps up or down?It takes fuel to build boost and heat. No fuel is lower on boost and heat.

 

[BV]

Silly question but is it possible a rodent (mouse or rat) moved into your air filter housing and is blocking your air intake?