I need help diagnosing a sudden loss of power on my 12 valve. Driving home from work today , the go peddle went dead. No smoke, no exhaust heat, low boost. Idles smooth & sounds normal. the first thing I did was change the fuel filter , it had no effect. thanks, doug

 

Sounds like a boost leak. Check all boot connections and then check the hose connection to the AFC. Others will chime in with more.

 

A boost leak would give smoke, wouldnt it??

sounds like a fuel pressure problem to me - do u have a guage setup to measure fuel pressure??

How about the overflow valve? Have you changed yours lately??

 

boost leak would cause high EGTs & smoke. I got so impute on the 12 valve thread, he suggested the fuel shutoff solenoid isn't pulling up all the way. Sounds like a a good bet I will check it in the morning . thanks for helping, doug

 

Dr. Evil:

Sorry, you're right about the smoke with a boost leak. I missed that in his original post. Time for glasses or a retake at the "Evelyn Wood Sped Reding" course. A fuel problem is more likely. Hope you get it found and fixed easily.

 

My vote is also for the shutdown solenoid not pulling up all the way. However, if the wastegate actuator diaphragm ruptures and leaks, or the aneroid line breaks, it will cause a boost leak AND loss of fueling, because the aneroid in the pump won't receive pressure.

 

the boot is torn & needs to be replaced . at that point I will clean & inspect linkage. Thanks ,doug