Still battling P0174

I posted previously the exhaust system on my new-to-me ’07 Sequoia is a crime scene, with aftermarket cats and the down tubes welded to the exhaust manifolds.

I'm still fighting with the P0174. The P0430 comes and goes... I did most of the things suggested in another post about the P0174. I put in new spark plugs, cleaned the MAF and throttle body, replaced the PCV valve and the hose to the valve, replaced the hose from the air box to the regulator on the passenger side, and did a couple of other things.

Unfortunately, the P0174 keeps popping up. The upstream Bank 2 sensor was marked Denso Toyota. I suppose it could be the original. So I replaced it with a new Denso Direct Fit unit.

No change. I still get the P0174, but I'm not getting the 420/430.

What should I try next?

Thanks,

 

Do you have access to a scan tool with data?

 

Have you opened the factory service manual and looked in there for the troubleshooting workflow on P0174?

 

after hunting al over for th cause of my p0171 and p0174, changing all the seals on the fuel injectors was eventually my culprit. i started at the least labor intensive and that was the hardest so it was the last( maf cleaning, pcv change, fuel filter change, replacing very minor-ly cracked hoses(just on the tips they were starting)


matt

 

Yeah, they bought a Autel MX808S back in Mar when they were dealing with the same P0174 and other things where showing us some Live Data was mentioned.

Dreaded TRAC OFF and VSC TRAC and Check Engine Lights | Toyota Tundra Forum

Another hose question


@poormxdad , with that new Autel, if you could post certain Live Data findings, especially the ones below, it might give us an idea of what's going on. Be sure to have your SEQ properly warm and take the readings in Idle.

You may know this by now but when you're reading Live Data with the Autel, you can place a check mark next to items of interest and then select Show down on the task bar. Take a screen shot and post results.