G
George H
Guest
Hello,
'88 buick 3.8 MFI
Motor is running way rich
all plugs sooty black but not wet
MAF fine
new o2 sensor (still need to test voltage but no matter in open loop)
Idles way to high, maf low sig. error because idle, not bad signal
tps tested and adjusted ok
iac appears to be working
if held at ~1/3 open throttle, will rev for a bit then start bogging continues to cycle (high, low, high low rpms) till finally bogs down and dies with noticible fore fire through throttle body.
Fuel pressure 30# regulated, 40# no vac..reg ok
No leaking inj. holds pressure
exhaust not restricted
can not find vac leaks (cause lean condition? and high idle, not rich condition w/ high idle)
temp sensors all tested within spec.
I'm lost as to where to look next. What I see is:
Something is telling the inj. to pump out alot of fuel....what and why if in open loop.
It's all the cyl. running rich so, intelligent not intermittant?
Seems to be running advanced to my pre-computer ear
'88 buick 3.8 MFI
Motor is running way rich
all plugs sooty black but not wet
MAF fine
new o2 sensor (still need to test voltage but no matter in open loop)
Idles way to high, maf low sig. error because idle, not bad signal
tps tested and adjusted ok
iac appears to be working
if held at ~1/3 open throttle, will rev for a bit then start bogging continues to cycle (high, low, high low rpms) till finally bogs down and dies with noticible fore fire through throttle body.
Fuel pressure 30# regulated, 40# no vac..reg ok
No leaking inj. holds pressure
exhaust not restricted
can not find vac leaks (cause lean condition? and high idle, not rich condition w/ high idle)
temp sensors all tested within spec.
I'm lost as to where to look next. What I see is:
Something is telling the inj. to pump out alot of fuel....what and why if in open loop.
It's all the cyl. running rich so, intelligent not intermittant?
Seems to be running advanced to my pre-computer ear