Ok thanks guys I moved injector #6 over to 1 and code followed with it, replaced injector and running like a champ THANKS!!!

 

Hey guys I have the P0171 too. I have a 1996 4runner complete stock. I am going to test the fuel pressure next, because all my vacuum lines are good. I will be testing the MAF sensor too, I have heard from many people that you cannot clean a MAF sensor. It damages it actually. Here is a link to test it. I will let you guys know what I have found after all the test I don't think it would be my 02 sensors because they were changed last year and the reponse between the two is very fast.http://www.ncttora.com/fsm/1996/SIL/.../mafm/insp.pdf

 

I just fixed a P0171 and I'll add my solution just for reference. First I tested the MAF and it met FSM specs. Then I thoroughly checked my intake system. It turns out that I had a loose hose clamp around the intake silencer. Actually, the stock clamp was tightened as much as it could go, but the rubber of the hose had actually crushed a little bit over the years. This resulted in a poor seal, ie large vacuum leak. A $1.50 hose clamp not only fixed the CEL, but also gave me back the 3 MPG that I’d been missing for the last year! I went from 17 to 20 MPG highway. Unbelievable!

The take home lesson: It seems like a no brainer, but make sure you check for vacuum leaks VERY carefully.

 

You can clean the MAF without damaging it. You just need to use MAF cleaner on it, let it dry, and don't touch the wires. People that say cleaning damages it either use harsh chemicals like carb or choke cleaner, solvents, etc.. or they physically clean the wires with a Q-tip or something.

It a good chance that a dirty MAF is your problem so I recommend cleaning it.

 

Hey guys so I tested a few things today and found out what the problem was. I first checked my MAF and it passed all the test fine. So I checked the fuel pressure on the vehicle and it was in perfect operating condition. Next I checked the engine temp sensor it was fine too. So I fogged my system to check for a vacuum leak. I found that there was a small crack in my intake tube between the MAF and throttle body so I found one in the local junk yard and replaced it. I cleared the code and I am pretty sure I fixed the problem I will let you know at the end of this week, if the light comes back on. Doing my timing belt this weekend!!!

 

Good work! How do you fog a system, I never heard that one?

 

I am getting a PO171 and w 181K miles on it, I am thinking I should just get a new MAF (than bother cleaning it and then buying a replacement anyways), since mine is pretty dirty and I just wanna try eliminate all causes for my persistent CEL problem.

my question is: should I buy the toyota dealer MAF or are others just as good? I found one on parts geek for $75 (A1 Cardone Air Mass Sensor Part Number: 7923-05004996). any suggestions? thoughts?

thanks, first time poster (and a first time 4runner owner, wohoo!!), awesome site, look forward to tricking out my runner.

 

I'm no expert on this, but I wouldn't replace the MAF before testing it per the FSM. It's an expensive part and you may end up getting an inferior one if you replace a good OEM MAF with an aftermarket version. Here's the link to the FSM testing procedure: http://www.ncttora.com/fsm/2000/Repa...0Flow/insp.pdf

 

I have thet stupid code to and I can't get rid of it it's not the maf it's clean and It tested within spec same with the o2 sensors tested fine. Absoultly no vacuum leaks intake leaks exhaust leaks no leaks at all. Injector are like new and if there was blockage it would misfire because I had that problem before. I tryed to check fule pressure but I messed up my fuel rail the last time I tryed because the 2.4 L are a pain to run a fuel test and use a totaly different fitting then any other toyota motor. I know the fule pump does not kick on unless the truck is running which is weird and it hesitates at around 3000 rmp when driving...it sounds like fule to me but I don't know for sure. It has a new pump, filter, plugs, wires, vacuum lines, ECT sensor. So if any of you have any idea please help me out

 

I got MAF problems with my 2000 3400 5VZ, already tried cleaning, still CEL and P0171 code, tried to test the MAF with a volt/ohm meter per Chilton's book, but lousy instructions gives me inconclusive results. Wondering if anyone has exact specs, volts and ohms, when testing this MAF.