04-30-2017, 01:09 AM
HOT IDLE 800RPM AT MAF OUTPUT PIN IS ( 1.7–2.0 volts) suz. spec, and TRUE.
YOUR PHOTOS I NOW REVIEW
i see the 02 front (only front matters, rear is EPA cat test toy) goes to 1 v, at time count. 6174. so we see it stick there, and that is WRONG,and is not exhaust leak (that causes 0v)
0v = lean max oxy, or exhaust leaks, 1v is rich, no oxy there.
exhaust cracks all suck in air (20% oxy) at the end of each PUTT. so no leaks allowed there.
the map data is only for EGR. this engine runs off MAF
the MAF data there, I presume driving (nice plot, very very nice) shows a HAPPY MAF.
The maF tracks TPS, super good and TPS works great.
ECT is HOT 189f , so thermosat is reglating ok and ECT works. all good,
whats left. seems all inputs to ECU are ok
so whats left
Fuel, pressure always tops list of 1st (not bad fuel , if fuel is bad or was bad, that be 1st)
fuel pressure on this engine is complex.
in fact if the FPR is bad, its hopeless case. the ECU ASSUMES it works perfect and injects from tables based on perfection there.
then uses maf data to inject,
if say the FPR sticks closed, and fuel pressure goes to 60psi, its a lost cause. fix this first.
one other cause is exhaust leaks, causing ECU to go Max rich, like yours is now.
unplug the front o2 connector.
run ok now?
when the 02 is inpugged, the voltage goes to .45vdc, (means perfect mix and lies to ECU) but hides, that exhaust leak now if present.
see>
the EFI sysem is slammed full rich,
172 tells you that
1v on 02 all the time tells that.
long term fuel trim will go to max NEGATIVE (trying hard to suck out all that excessive fuel)
why is the engine rich. that is the path, tests and final solutions.
ever use a fuel pressure gauge.?
other causes, are leaking injectors.
try some Chevron techron additive in the tank? its the most powerful of all, , i dont like additives but can be a useful diagnostic tool, if it injects better now, the injectors may be failing...
YOUR PHOTOS I NOW REVIEW
i see the 02 front (only front matters, rear is EPA cat test toy) goes to 1 v, at time count. 6174. so we see it stick there, and that is WRONG,and is not exhaust leak (that causes 0v)
0v = lean max oxy, or exhaust leaks, 1v is rich, no oxy there.
exhaust cracks all suck in air (20% oxy) at the end of each PUTT. so no leaks allowed there.
the map data is only for EGR. this engine runs off MAF
the MAF data there, I presume driving (nice plot, very very nice) shows a HAPPY MAF.
The maF tracks TPS, super good and TPS works great.
ECT is HOT 189f , so thermosat is reglating ok and ECT works. all good,
whats left. seems all inputs to ECU are ok
so whats left
Fuel, pressure always tops list of 1st (not bad fuel , if fuel is bad or was bad, that be 1st)
fuel pressure on this engine is complex.
in fact if the FPR is bad, its hopeless case. the ECU ASSUMES it works perfect and injects from tables based on perfection there.
then uses maf data to inject,
if say the FPR sticks closed, and fuel pressure goes to 60psi, its a lost cause. fix this first.
one other cause is exhaust leaks, causing ECU to go Max rich, like yours is now.
unplug the front o2 connector.
run ok now?
when the 02 is inpugged, the voltage goes to .45vdc, (means perfect mix and lies to ECU) but hides, that exhaust leak now if present.
see>
the EFI sysem is slammed full rich,
172 tells you that
1v on 02 all the time tells that.
long term fuel trim will go to max NEGATIVE (trying hard to suck out all that excessive fuel)
why is the engine rich. that is the path, tests and final solutions.
ever use a fuel pressure gauge.?
other causes, are leaking injectors.
try some Chevron techron additive in the tank? its the most powerful of all, , i dont like additives but can be a useful diagnostic tool, if it injects better now, the injectors may be failing...
http://www.fixkick.com