I've been chasing down an engine power loss problem and the fix has eluded me for some time. I'll tell you the symptoms first and then what's been replaced or checked.
Symptoms:
What's been done:
Fuel pump - symptoms are usually different though
Distributor - not sure about this
Injectors - wouldn't a faulty injector cause a bad emissions reading?
Exhaust - something stuck in pipe between manifold and cat?
Anything else worth checking? Thanks!
Symptoms:
- Obvious seat of the pants power loss at all speeds
- Engine runs noisier (exhaust louder)
- RPM steady throughout (no missfires)
- At least a 3-4 MPG loss
- Engine runs hotter than normal
- It feels like I'm towing something heavy
- Lose speed coasting down hills that normally cause it to gain speed
- Just recently the RPM at idle is reading near zero on the gauge, but there's no perceived loss in RPM
- No stumble or hesitation
- Auto tranny shifts later than normal and it's a hard shift
What's been done:
- Every sensor replaced (except for CPS in distributor)
- All new tune up parts (many times over)
- Rebuilt head
- Good seal on intake/exhaust manifold
- Replaced cat
- Replaced computer
- Checked continuity between sensors and PCM connector
- Good coil
- Fuel system pressure checked
- Replaced fuel pressure regulator
- Replaced fuel filter
- Passed emissions (figure compression good as a result)
- Disconnected exh. pipe before cat and ran it w/ no change
- Seafoam treatment
- Ran can of BGK44 in fuel
Fuel pump - symptoms are usually different though
Distributor - not sure about this
Injectors - wouldn't a faulty injector cause a bad emissions reading?
Exhaust - something stuck in pipe between manifold and cat?
Anything else worth checking? Thanks!