10-25-2015, 09:33 PM
Welcome BRUCE.
did car sit unused for a year>?
the main must open with about 8inches HG vacuum pull, it has a valve there, that open wide, can be done in hand to be sure it repeats and dont stick open as they love to do (and stall car at every stop light)
if the stall test fails, then the exh path is locked,
this car my guess is the horrible quad port EGR, deep hidding intake x4 EGR injection point.
if the input exh path to egr and the output paths are clear , the stall works. (400 on robust engines)
stumble and surge.
defeat the EGR, make sure its closed and see if it stumbles now,,, (just pull EGR main hose , and plug it with say a golf tee)
now if it runs bad. its not EGR, caused.
1;seems that is RPM surge, not misfiring?
when you are driving, and it surges where is your right foot doing, off pedal?
but at 60mph the pedal is depressed and the idle switch can not close , at 60mph so its not a maladjusted idle switch that causes the ISC to go nuts.
must be pure injection rates wrong.
and air leak , only makes power on this engine pure strong power.... same as right foot does. (speed density systems)
i wonder if :
fuel pressure is surging?, (if is bingo) FPR bad? or worse the FPR, vacuum nipple leaks fuel, (bad FPR and most are now, this old)
8v TBI single injector , o-rings cracked. do the key off am i dribbling test , air horn removed? find both failures, o-rings or injector leaks.
more.
does the ECU flash code 12? on demand?
or flash 12s driving and surging.
the surge might be pure air. related. if injection looks ok. the EFI matches fuel to air , actual flowing. so....
vacuum booster leaks. (vacuum pipe)
or some other vacuum line or device leaks air. and varies by time. /heat /virbration, etc.
cheers kick
did car sit unused for a year>?
the main must open with about 8inches HG vacuum pull, it has a valve there, that open wide, can be done in hand to be sure it repeats and dont stick open as they love to do (and stall car at every stop light)
if the stall test fails, then the exh path is locked,
this car my guess is the horrible quad port EGR, deep hidding intake x4 EGR injection point.
if the input exh path to egr and the output paths are clear , the stall works. (400 on robust engines)
stumble and surge.
defeat the EGR, make sure its closed and see if it stumbles now,,, (just pull EGR main hose , and plug it with say a golf tee)
now if it runs bad. its not EGR, caused.
1;seems that is RPM surge, not misfiring?
when you are driving, and it surges where is your right foot doing, off pedal?
but at 60mph the pedal is depressed and the idle switch can not close , at 60mph so its not a maladjusted idle switch that causes the ISC to go nuts.
must be pure injection rates wrong.
and air leak , only makes power on this engine pure strong power.... same as right foot does. (speed density systems)
i wonder if :
fuel pressure is surging?, (if is bingo) FPR bad? or worse the FPR, vacuum nipple leaks fuel, (bad FPR and most are now, this old)
8v TBI single injector , o-rings cracked. do the key off am i dribbling test , air horn removed? find both failures, o-rings or injector leaks.
more.
does the ECU flash code 12? on demand?
or flash 12s driving and surging.
the surge might be pure air. related. if injection looks ok. the EFI matches fuel to air , actual flowing. so....
vacuum booster leaks. (vacuum pipe)
or some other vacuum line or device leaks air. and varies by time. /heat /virbration, etc.
cheers kick
http://www.fixkick.com