Misfire Mayhem
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Joined: 06-01-2023
Posts: 31
From: centralia
...and make sure you plug it back in.
P0172 means the ECU thinks the trim required to correct an initial rich a/f condition is excessive. I think that could mean either the injector orifices are too big or they're leaking. That would also explain the hard starting. Do you still have your original injectors from the original motor?
P0172 means the ECU thinks the trim required to correct an initial rich a/f condition is excessive. I think that could mean either the injector orifices are too big or they're leaking. That would also explain the hard starting. Do you still have your original injectors from the original motor?
Thread Starter
Member
Joined: 06-01-2023
Posts: 31
From: centralia
However, the fact that you can smell the excess gas fumes would mean that the sensors are wrong and needlessly dumping fuel in. I am slow to blame injectors and computers for every problem.
A vacuum leak between the MAF and #1 O2 sensor. Brake booster hose, anything connected to the intake manifold, air tube to throttle body, any tube made of rubber under the hood etc.
Bad MAF, Bosch O2 sensor, purge valve not hooked up tight.
One of the most overlooked points is the air tube to the TB, it cracks where the PCV tube connects or does not get tightened down. Another is the brake booster tube.
A vacuum leak between the MAF and #1 O2 sensor. Brake booster hose, anything connected to the intake manifold, air tube to throttle body, any tube made of rubber under the hood etc.
Bad MAF, Bosch O2 sensor, purge valve not hooked up tight.
One of the most overlooked points is the air tube to the TB, it cracks where the PCV tube connects or does not get tightened down. Another is the brake booster tube.
i havent replaced the air temp or manifold pressure sensors... of course no codes for them
havent done water temp either... gauge reads fine ...
idk im out of ideas...
will update after i get new o2 sensors in
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Joined: 06-01-2023
Posts: 31
From: centralia
Senior Member
Joined: 12-05-2014
Posts: 3,371
From: Northern Ohio
You said in #11 "...i swapped injectors around and that was it so new injectors runs great!!!...
But you still had P0017 at that point. And it's too rich at startup, so not that great. I don't know how that happens with an air leak.
Could be a problem with the MAF sensor, but what new injectors did you get?
But you still had P0017 at that point. And it's too rich at startup, so not that great. I don't know how that happens with an air leak.
Could be a problem with the MAF sensor, but what new injectors did you get?
Thread Starter
Member
Joined: 06-01-2023
Posts: 31
From: centralia
alright so.... new up and downstream o2 sensors... the p0172 fuel trim system rich... it returned.
with all other ideas exhausted, I removed and cleaned the throttle body, idk it appeared spotless inside.
also, the air temp sensor I sprayed out with MAF sensor cleaner.... so far p0172 hasn't returned, it usually returned after about 30 min of running so far hour and a half at idle couple runs down the road, so fingers crossed!!!!!
BUT.... still long start after it sits.
it did have to turn over 8-10 times before,
with the new fuel pump only 3-4 times so it made a difference.
both evap purge and vent solenoids replaced, and there's no inline filter idk what else it could be.
with all other ideas exhausted, I removed and cleaned the throttle body, idk it appeared spotless inside.
also, the air temp sensor I sprayed out with MAF sensor cleaner.... so far p0172 hasn't returned, it usually returned after about 30 min of running so far hour and a half at idle couple runs down the road, so fingers crossed!!!!!
BUT.... still long start after it sits.
it did have to turn over 8-10 times before,
with the new fuel pump only 3-4 times so it made a difference.
both evap purge and vent solenoids replaced, and there's no inline filter idk what else it could be.
Thread Starter
Member
Joined: 06-01-2023
Posts: 31
From: centralia
You said in #11 "...i swapped injectors around and that was it so new injectors runs great!!!...
But you still had P0017 at that point. And it's too rich at startup, so not that great. I don't know how that happens with an air leak.
Could be a problem with the MAF sensor, but what new injectors did you get?
But you still had P0017 at that point. And it's too rich at startup, so not that great. I don't know how that happens with an air leak.
Could be a problem with the MAF sensor, but what new injectors did you get?
Senior Member
Joined: 12-05-2014
Posts: 3,371
From: Northern Ohio
I'm also suspicious of your new injectors. To clarify, did you or did you not still have a P0017 at the time you changed those injectors?
