help with loss of power

[glhx]

ive lost 25% of my power. a/f gauge is bouncing from lean to rich every half second. drop a gear to high rpm car sometimes backfires out the exhaust and a/f gauge goes to solid rich with two green bars. compression is 130 on all 4. spark is present on all 4 at idle. boost is 8psi. power loss is all rpm ranges. cars not slow by any means but the kick is gone

[Sittn86]

Codes? Mods? A/F gauge is only accurate at WOT.

[glhx]

no codes.no mods. af gauge usually sits right in the orange stoich area no matter what rpm range.

[NAJ]

Start with basics, Cam Timing, Ignition System Malfunction creating weak/no spark condition, open/shorted ignition/coil wire,crack in ignition coil, cracked dist cap, fouled or damaged spark plug etc.
Spray ignition with water from a spray bottle looking for arcing to ground.

[detobias]

Quote:

Originally Posted by glhx no codes.no mods. af gauge usually sits right in the orange stoich area no matter what rpm range.

thats a little weird

most AF gauges will 'bounce around' the middle when the compy is in 'closed loop' i.e. during normal, warmed up, part-throttle operation

at WOT, the AF gauge should go steady rich

+1 on NAJ's suggestion to start with the basics

[phantomrt]

It is normal for the air/fuel ratio to bounce back and forth during normal cruise and idle and go rich under heavy throttle.

What about ignition timing? Sounds like some kind of misfire and its dumping unburned gas into the exhaust and causing the backfire.