Engine code P0172 issues.....

[SleeperSolara]

Alright. I've been havin' this issues for the longest time and it's makin' me really irritated.....

P0172 is: 1. Incorrect fuel line pressure.
2. Leaking injector.
3. Heated oxygen sensor (bank 1, sensor 1) malfunction.
4. MAP or MAF sensor malfunction.
5. ECT sensor malfunction.

So i tackled the issues 1 by 1.
First was the "incorrect fuel line pressure". Thought it would be from a clogged fuel filter. Changed it, cleared code. Code came back.
Then thought the incorrect fuel line pressure could be from a bad fuel pressure regulator and fuel pump, changed both. Cleared code. Code came back.
After that, thought it could be the "heated oxygen sensor (bank 1, sensor 1) malfunction". Pulled one from an Avalon. Changed out old one. Dad checked old one, it was bad. Cleared code. Code came back.
After that, thought it would be "MAF sensor malfunction", swapped from Avalon. Dad checked one from the Solara, it was still good. Cleared code. Code came back.
After that, thought it would be "ECT sensor malfunction", swapped out from Avalon. Cleared code. Code came back.
So i was gettin' fed up, and after a couple of hard runs i would noticed and slight burnt smell like gas. Knew it had to be the injectors.
The car would idle weird and fluctuate, and once in a while it would randomly die in traffic while idlin'.
Pulled 9 OEM 1MZ injectors from 2 Avalons, had my friend from a well known injector service shop clean them for me, also ordered new injector o-rings. The whole nine yards.
I got so pumped up to install the new injectors today in the mornin'. Took me 1 hour and 30 minutes to install everythin'.
Cleared the code cause battery was disconnected. Cleaned the area around the injectors [It was hella nasty wit black grease and dust, made me sick lookin' at it on a cotton swab] .
Got everythin' put back together, fired up the Solara, idled hella rough for abit.
Then ran fine, and headed to school.
After i got out of school, CEL code came back.
Stopped by AutoZone and had them pull the code..... Same P0172 code.....
Car doesn't idle rough at all, once in awhile it would dip low in idle.
Exhaust does smell funky though......

Anyone have any other ideas what could be wrong??
The guy at AutoZone said I should let it run through and the ECU should clear itself [Neva heard that before.....].

[corlon]

perhaps the wiring going to one of the sensors listed is intermittently grounding out? do you always get gas from the same place? maybe something with the fuel or water in your tank? ???

[02slera]

^^^ i agree you should check the wires for damage.
what sticks out to me in your description is "heated oxygen sensor (bank 1, sensor 1) malfunction" because you said your old one checked bad. i would pull the one you have in there now and have it tested. even if you tested it before you put it in. the only reason i go towards that is because in your whole description, that's the only place you actually found a problem so far. other than that i would check spark plugs and wires. i dont know if its possible that an incomplete combustion because of a bad spark could cause idle issues, a gas smell, and foul up an 02 sensor, it would probably throw a different cel if that was the case though.

[SleeperSolara]

perhaps the wiring going to one of the sensors listed is intermittently grounding out? do you always get gas from the same place? maybe something with the fuel or water in your tank? ???

All the plugs and wires are good when i looked at them.

^^^ i agree you should check the wires for damage.
what sticks out to me in your description is "heated oxygen sensor (bank 1, sensor 1) malfunction" because you said your old one checked bad. i would pull the one you have in there now and have it tested. even if you tested it before you put it in. the only reason i go towards that is because in your whole description, that's the only place you actually found a problem so far. other than that i would check spark plugs and wires. i dont know if its possible that an incomplete combustion because of a bad spark could cause idle issues, a gas smell, and foul up an 02 sensor, it would probably throw a different cel if that was the case though.

I have a set of Gen 2 Solara spark plug wires on the car, and Magnacor spark plug wires.
The spark plug wires are good.
If i was gettin' a bad spark it would throw a cylinder misfire.
There is no gas smell anymore.
Just a funky slight rough idle once in awhile.
I think it might be the ECT sensor, MAF, or heated O2 sensor....
The Haynes repair manual states that the "ECT: monitors engine coolant temperature and sends the PCM a voltage signal that affect PCM control of fuel mixture, ignition timing, and EGR operation."
That's why i think i might be the ECT..... but i replaced it wit another one.....