P0171

Hey guys, I just got this code a few moments ago and wonder if anyone knows how to read the Freeze frame that that goes along with it. I just hope it is not the fuel pump. I saw some solutions but they are for 1st Gen Tacoma. Going to clean the throttle body and MAF sensor today and hope that helps.

 

Also just to this I did get this code a week ago as well but it went away the day after.

 

I believe if it was a fuel pump, you'd see this for both banks. In my experience, the issue is usually related to the MAF or O2 sensors.

 

Both banks are wildly lean.

Most likely MAF or fuel pump.

A good visual check to make sure no hoses are off causing a massive vacuum leak is a good start.

 

I got ya. I was just going off of the single code, mostly.

Either way, it doesn't hurt to at least clean the sensors and see if that helps.

 

Huh?

Your engine had been running for 16+ mins.
And your coolant temp is only 86 degrees?

And you’re in closed loop?

 

It is. See the pic.

 

Yeah, I know. I seen that.
But that seems kind of early to go into closed loop with an ECT of only 86F degree (30c)

@Bishop84 you ever seen an engine run for 16 mins and only read 86 (30c) on the ECT.
And also be in closed loop?

 

lol I see 86 and think C, which is dead on operating temp.

 

Closed loop on 2nd gens has nothing to do with coolant temp but yea that doesn't seem right although I've found that freeze frame data isn't always the best.

I would want to look at fuel trims at idle as well as during various driving conditions first.
And see what actual coolant temp is.

 

OP is down in Texas with you.
Even in Tennessee, if I let my truck run for 16 mins. It’s warm……up to operating temp.
Even in the winter.

 

I will agree with the rest.
Those trims are way high.

 

As @Bishop84 said it may be in C.
Anyway modern vehicles go into closed loop as soon as the upstream O2/AFR sensors are heated and ready which is typically 1-2 min on a cold start and under a min on a hot start.

 

Gen3 goes to CL pretty much right after startup

 

And now I just got the P0174 as well. Think It may be a bad pump

 

You’ll need to check the pressure.
It’s never fun doing fuel pumps.

 

Depends. On some older trucks and cars it was easy like on my 1987 & 1993 Nissan hardbody. On most modern cars it is a pain. I don't know how difficult it is for the Tacoma.

 

You need a t-style adapter.

 

Well it seems to have gone away on its own again. Short trim has gone to the negatives and the long trim are below 20. Will try to get a pressure test done to see if it is the fuel pump soon

 

Best time to do some testing would be when the trims are climbing. If they're in the process of self correcting (going down) then the problem may have gone away, at least temporarily..