intermitent injector failure cyl3 eratic idle

S13<3

S13<3

SFLDrama.com
Driver
ecu throws code 33, the car starts up right away, but wont respond to throttle input, the rpm's go down then kinda go back up when given input, it also wont idle under 1k and if it does it stumbles and dies, the a/c-auxillry fan turns on for no reason whether the car has reached operating temp or not, even before the gauge registers anything the fan turns on for no reason, ive swapped injectors, theres no vacuum leaks, brand new pump and tried a different fpr(i need to get a gauge to see actual pressure but i feel its not the problem) swapped dizzy, cts is new, o2 sensor is new tps is new and properly adjusted, the ecu had been swapped, im seriously at a loss here what the issue could be, it only leaves the iacv and aiv that could be gunked to shit? idk any help is much appreciated
 
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Maybe a video will help
View My Video

its running as rich as can be, blowing black smoke and breaking up as can be heard in the video
swapped the iacv last weekend with no luck, tried a different maf off a running car no luck, swapped the whole rail with a spare i had same shit, still throwing code 33, vacuum reads 20 when ever the idle decides to settle under 1k, im at a fucking utter loss what is making the car run like absolute shit, when i disconnect the maf it runs a little better and as soon as its plugged back in it runs like straight shit again, swapping it made zero difference
 
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o2 is brand new and has continuity all the way to the ecu plug
under remedies for code 33 it lists:
sensor/harness> tests out fine
intake air leaks> reading 20in of vacuum
fuel pressure> got 40psi varies with vacuum
injectors> have been swapped 2 times, theres no way 12 injectors in a row are bad

which leaves me back to square one, wtf could be wrong
 
S13<3 said:
o2 is brand new and has continuity all the way to the ecu plug
under remedies for code 33 it lists:
sensor/harness> tests out fine
intake air leaks> reading 20in of vacuum
fuel pressure> got 40psi varies with vacuum
injectors> have been swapped 2 times, theres no way 12 injectors in a row are bad

which leaves me back to square one, wtf could be wrong
Click to expand...

did you check for short to ground on the o2s circuit.
 
This may sound stupid but try this, take off the air filter and raise the intake pipe up so it gets fresh air, do it while the car is on that way you can see any changes, also check the rod and see if it adjusted right. Good luck
 
If it's shooting serious smokage, perhaps all of the injectors are firing badly? did you try checking the pigtails with a noid light or test light to make sure they're nice and flashy throughout the rpm band? If not they aren't, I would look more on the electrical end... perhaps a bad ground somewhere on the block or ecu fault... How did the spark plugs look? all of them carbon'd up? or just cyl 3?
 
havent checked with noid lights yet, spark plugs are all black all cyl running rich
just finished painfully swapping the pcv valve and all its hoses, motor still runs like shit super rich misfiring and all that good shit, but code 33 went away and was replaced with code 12 which is the maf, swaped maf and same shit, tested the harness and im getting 10v where i should be getting 0.2v
also code 34 (knock sensor) wont go away for shit even tho the sensor and subharness are brand new

is it possible my engine harness went bad all by itself and i been chasing the wrong problem this whole time?
 
And you're certain there are no bad grounds? Has the harness been cut anywhere in the bay??

The code 34 can definately be being triggered by it pinging too much (misfiring, as you said), and that should cause it to dump excessive amounts of fuel as well, and the o2 sensor code would also be triggered because of the obvious rich condition. MAF sensor can and will cause all of that. I know you said you switched it already, but are you certain you got a good one?

The only other sensor that I think might cause problems (like it staying in open loop too long or the radiator fan staying on) is the coolant temp sensor... Test all of those, hopefully it is just the MAF. If you can access a scan tool, look at the voltage values in the ECU for the maf and ensure that it is changing properly when you accel/decel. And make sure you have a good reading for coolant temp sensor, tps, and your o2 sensors are switching good.
Good luck buddy :)
 
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