I think my o2 sensor might be going , major power loss and running super rich... , does anyone know if its possible to test one ? and is there different sensors for different models... like could I take my 86 gx 02 ... and try it in my 87 turbo to see if its the problem?

 

The O2 sensor is only used under light throttle cruising conditions (and idle too I think) to improve fuel economy, so if you're having acceleration problems, you're looking in the wrong place.

When exactly are you experiencing a lack of power? At all times, or only when you do something specific?

 

I'm losing power through out the whole range.. in the lower gears there is still some , but 4th and 5th drop off .. especially 5th .. around 100 in 5th under 10lbs boost wide open and no more acceleration ... the engine has 7000 kms on it . and 5000 of that was without boost and the rest has been under only 10 lbs . It used to be wild ... supposed to be putting out over 300 hp but it feels like I'm driving a geo metro, no coolant loss... all the vac lines look fine , I don't know what it could be

 

compression test.

 

Blown engine. If you have a stock fuel system, cranking the boost up did it.

 

its got street ported block , upgraded injectors and a few other things done to the intake... do you really think 10 lbs would damage anything..? My last block was running 15 psi with the same setup . it ran like that for 60 000 kms...