Code 31

rawmk3

New Member
Jul 5, 2008
170
0
0
IL
ccwade;1137670 said:
I am getting codes 24 and 31. I changed out my air filter and saw that the AFM housing needed cleaning, so I proceeded to clean out the whole unit, but unfortunately I need not remove the AFM. So I got a used one off of ebay but the same thing happened. I then check all my hoses in the air system. I found that the Air cleaner hose, the one that goes from the turbo to the afm, had a big tear in it. So I replaced that one with a new one. I thought and hoped that would fix it. No such luck. Both AFM's produce the same results. Idles fine but upon acceleration, spits and sputters. I am going to do what you suggested. check the wires and clean them also, again.
Is it possible to have 2 bad AFM's? Is there anyway to get me one that has been tested on a car that runs good? I really am getting frusterated with this. I would appreciate any help or suggestions. I need to get my car running ASAP.

I had the same thing happen to me. My car would run like crap but only at times. What I ended up finding after almost losing my mind testing and retesting everything, there is a brown wire that comes off your AFM that will T up with a brown line off your ECU temp switch. My wires were all corroded, and broken in that area. Prolly just alot of heat on that side from the turbo made the wire loom weak. But after I replaced those wires (i replaced more than the 1 because others were in bad shape too ) I have not had a problem with the car. I would say its worth a shot to look at it. And according to the wiring schematic it comes from E2 off the ECU, and goes to the TPS, water thermo sensor, and the AFM. Its a brown wire, about 12ga or so.
 

rawmk3

New Member
Jul 5, 2008
170
0
0
IL
And grim, saying any turbo cars AFM would work, is that correct? Cause I believe I read there are 2 different plugs for the turbo cars for the AFM.
 

ccwade

supraman
Dec 27, 2006
32
0
6
Central US
thanks rawmk3 for the information. I will check that brown wire. if that wire is corroded, would that cause my afm to be all over the place with the hz?
 

grimreaper

New Member
Jul 2, 2008
2,180
0
0
Dallas
rawmk3;1139731 said:
And grim, saying any turbo cars AFM would work, is that correct? Cause I believe I read there are 2 different plugs for the turbo cars for the AFM.

gte= 5 wire plug
ge= 7 wire plug
 

rawmk3

New Member
Jul 5, 2008
170
0
0
IL
ccwade;1139950 said:
thanks rawmk3 for the information. I will check that brown wire. if that wire is corroded, would that cause my afm to be all over the place with the hz?

Honestly I dont know for sure if that would mess with your frequency range, but I believe e2 is a ground line, and that can mess alot of things up if not correctly attached. I would check the wiring in these old cars anyway, and replace what needs to be replaced by soldering in new pieces, and putting a shrink wrap over them for moisture protection. That way you know your wires are in good shape from what you can tell. Cracked electrical wires are bad news, because it oxidizes the lines and causes resistance in the circut.
 

figgie

Supramania Contributor
Mar 30, 2005
5,225
16
38
50
Twin Cities, Minnesot-ah
heat shrink wrapping will not help in moisture protection. As a matter of fact, Heat shrinking will help in condensation pooling.

For true moisture protection, you need heatshrink with glue inside of it. That is the only way to moisture proof a heatshrinked area.
 

rawmk3

New Member
Jul 5, 2008
170
0
0
IL
figgie;1140121 said:
heat shrink wrapping will not help in moisture protection. As a matter of fact, Heat shrinking will help in condensation pooling.

For true moisture protection, you need heatshrink with glue inside of it. That is the only way to moisture proof a heatshrinked area.

True, but then again, I kinda look at that as a common thing. Sorry for not being clear enough on that. Heat shrink tubing on its own isnt water tight sealing. There needs to be an adhesive.
 

ccwade

supraman
Dec 27, 2006
32
0
6
Central US
Can anyone tell me which lexus afm's if any, have the same electronics and HZ range as the stock afm for a 91 turbo? do i have to mod anything if i only use a lexus electronic unit? thanks.
 

supramang

New Member
Jun 14, 2008
74
0
0
Farmington
oh what a shitty day.... I woke up with my sinuses clogged halfway around my head, then I realized my alarm clock was not beeping like usual. hmm.. turns out it was 7:21 am. School starts at 7:30, So I get ready in record time and dash to my car, everything is good idles fine so I head down the street and as im about to shift to third it jerks violently and that damn orange engine light pops on. So I sputtered all the way to school and later found that my inlet pipe off the turbo was loose as well as the 3000 pipe.... tightened them up, inspected them for cracks (all good) and the light still comes on with the unsatisfactory effects :( So figgie and I believe the electronics for the afm has taken its last breath of sweet morning air.
 

rawmk3

New Member
Jul 5, 2008
170
0
0
IL
Did you pull the EFI fuse to reset the codes? And if the AFM did take a crap, sorry to hear that. That really blows.
 

grimreaper

New Member
Jul 2, 2008
2,180
0
0
Dallas
unplug the afm and you can at least make it home in limp mode. sounds like shes toast.
mine got worse and worse and finally decided it wasnt going to let the car start.
 

figgie

Supramania Contributor
Mar 30, 2005
5,225
16
38
50
Twin Cities, Minnesot-ah
Ryan!

those AFM electronics are starting to be scarse!

Look for them on ebay and also try the VPC too. Sometimes you can get lucky. I sold my AFM electronics off a while back :(

BTW I see a couple of AFM with electronics on the bay.
 

grimreaper

New Member
Jul 2, 2008
2,180
0
0
Dallas
i have one, but bust out your knee pads, its gona cost....

Dont pay to much! They are all 20 years old! If you had the $$$ id heavily consider going speed denisty and not having to worry about the damn thing anymore.

figgie what do you run for air metering purposes?
 

supramang

New Member
Jun 14, 2008
74
0
0
Farmington
rawmk3;1142839 said:
Did you pull the EFI fuse to reset the codes? And if the AFM did take a crap, sorry to hear that. That really blows.

Yeah I reset the EFI fuse it didnt do much for me. Im pretty used to pulling that thing, ive had quite a few electrical problems with this engine.
 

figgie

Supramania Contributor
Mar 30, 2005
5,225
16
38
50
Twin Cities, Minnesot-ah
supramang;1143779 said:
Yeah I reset the EFI fuse it didnt do much for me. Im pretty used to pulling that thing, ive had quite a few electrical problems with this engine.


and I can vouch. It wasn't his doing! It was the previous owner that unloaded the car "cheap". Not cheap enough after all this issues! lol. :)
 

rawmk3

New Member
Jul 5, 2008
170
0
0
IL
figgie;1144091 said:
and I can vouch. It wasn't his doing! It was the previous owner that unloaded the car "cheap". Not cheap enough after all this issues! lol. :)

Hahaha, sounds like my deal. Guy unloaded the car for 800 bux. And has been one thing after another. So now I have to hell with it, and decided to basically strip it down to nothing, and start over again. Most wiring redone, the entire engine gutted and rebuilt (other than crank hopefully) and alot of unneeded things are going, like AC, and ABS. All heating and AC is gone as of today (finally pulled the dash) and the ABS is going so I can hook up my line lock system. I want to go a little different than some of the cars I have seen thus far.
 

supramang

New Member
Jun 14, 2008
74
0
0
Farmington
Ha yeah picked up this one for 800 too. I only used it for the engine and driveline + comp. etc.... I had a ge with the w58 and besides the head gasket I never had a problem but this wiring harness sucks!! I dont have much money or time either because of school and cross country so thats no good.