runner89

Did something a little silly today.. Opened up the afm to see if I could clean it. Put it back together and my car won't hold an idle. It'll start up for a couple seconds and then die. It was pulling codes 31 & 32:
- 31 is air-flow meter signal-VC circuit open/VC-E2 shorted when idle contracts are closed.
- 32 is Air flow meter signal - E2 circuit open/VC-VS shorted.

Took it back out, messed around with it a little bit, stuck it back in, cleared the codes, and started it back up. Now it pulls a code 51:
- 51 is Switch signal - A/C switch ON. Neutral start switch OFF, Idle switch OFF during diagnostic check.

Been led to believe 51 has to do with your TPS. Could have messing with the MAF also thrown the TPS off too?

Attached pics are what the afm plug is supposed to look like, I think. Is this right?
http://share.shutterfly.com/osi.jsp?i=EeAtmLVk2bNmK8

Thanks - Chris

MTL_4runner

Only trucks with a 3.4L will have a MAF, what you have is an AFM (air flow meter).
They work very differently and yours does not need cleaning like a MAF would (but it does need adjustment).

These sites should help you with what you need to know:
http://www.autoshop101.com/forms/h34.pdf
http://www.4x4wire.com/toyota/minutemods/afm/


What you did was take out the connector, but the potentiometer is the large black part in the center:


Reconnect everything back together and adjust it properly and all should work again.

nunsa

Greetings,
A little FYI on AFM's: If you intend to mess with one to lean or richen your mixture it is very important that you mark the position of the cam and spring, now with that being said, I have mine advanced 3 notches, but I also have it marked in the event I want to return it to the factory "Lean Spec"
The code 51 is usually caused by a bad TPS, but not always. The AFM, TPS O2 sensors are all connected as are various other sensors. One thing affects the other, "For every action there is a reaction!" Newtons theory. You are going to have to re-check your AFM and put it back to spec. It's a long drawn out process, you have to lean it or richen it and keep clearing the code until it's gone. A code 51 is also a catch-all code it could also be your O2 sensor or any other sensors. Is your Rig still running rough? If your AFM is off, meaning rich or lean you'll know it - your mpg's will suffer, hopefully you went lean vs. rich. As a too rich condition will dilute your oil and wipe your bearings clean, and that's not a good thing! Good Luck, let us know how you make out!

runner89

Sorry about the mix up. Got her running again. Ended up taking the cover off the AFM to see what was going on in there. Part of the problem was that the feul pump contacts were not making a good connection(I had had kinda skewed them when I was tring to fish the plug in to the AFM with the top still on.

Anyways thanks MTL for the links.

Now that I have the top of the AFM off I think I am going to try to adjust it. We'll see how it goes. I think I going to try the lean direction first, as I already get lower gas milage, could use more low end power; and after a new o2(factory), new cat and back exhaust, I'm still blowing fuel through the exhaust. I'm going to drive it around for a day and then check for new codes before I do anything though. I'll update.

my final Question is this the way the small contacts in the middle are supposed to be(in the attached picture), at a 90 degree angle or are they supposed to be wraped around the bottom contact? Presently I have them wrapped around the contact.
http://share.shutterfly.com/osi.jsp?i=EeAtmLVk2bNmK8

thanks again

runner89

It is running smooth again. Didn't drive it around yet, just let it warm up. With the check connectors jumped and the engine running I'll rev it and Code 51 will run once then it will go back to a constant blink. We'll se tomarrow if it will throw a code into memory.