I recently purchased a "new" remanufactured AFM after discovering the one on my Land Cruiser was not the correct AFM. However, when I plug in the "new" AFM, the Check engine light does not illuminate anymore, and it will not start now. If I plug the old one back in, the check engine light appears, and it starts. This is actually the second "new" AFM that I have purchased. I thought the first one I purchased may have been damaged internally through shipping, but the second one is doing the same thing. I'm currently in the process of replacing basic LC maintenance issues, for example, the fusible links that I have read about on the forums, and ran across this issue. I have also read and gone through the no CEL-No start diagnostic sheet, and everything seems to check out, so any help is helpful. Thank you.
1991 FJ80 3FE AFM issues. (1 Viewer)
- Thread starter ASUAREZ27
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How did you discover it was "not the right one"? It sounds like the one currently in there is working fine. Maybe I'm not getting the whole picture, but it kinda sounds like a case of, "if it ain't broke, fix it 'til it is". What issue are you having that you suspect the AFM is an issue?
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- #3
Has not been running right at all. Rough idle, bogs down, etc. Aside from that had a large gap where AFM bolts up to the air box lid. The bracket with the one 10 mm that has the two holes wouldn’t line up at all and the diameter size of the hole was MUCH smaller then the size of the “new” correct one.
The "large gap" is what's causing it to not run correctly. Any unmetered air entering the system will cause these issues. The top end of the 3FE wants to be air tight.
If the CHECK ENGINE light does not illuminate with the key in the ON/RUN position before cranking the starter, this engine will not run. Don't even bother cranking it.
Please see the documents linked below for more information.
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- Thread starter
- #5
Since you have posted @jonheld I have gone through the 3fe diagnostic cheat sheet like 3 times making sure I have not missed anything and I have all 12v where I need it even checked the grounds making sure they are good. So when I go to plug in my “new” correct AFM the check engine light still does not illuminate now I know on the cheat sheet it says with the AFM unplugged if it illuminates it could be the internals of the AFM but this is the second correct afm that I am using. Now If I go plug in the incorrect AFM check engine light turns on and it will fires right up but obviously runs like crap.
Obviously the correct AFM is working. As for CEL, there could be a numerous reasons, i think you have other issues that are unresolved. Pull the code and see...
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- #7
I do not believe it is the correct AFM though because of the rough idle, bogging down and not sealing correctly. For example the intake tube is way to big for the diameter of the afm opening I have to crank down on the hose clamp on the intake tube just to get a tight seal and I know that’s not correct. The thing is the LC only reads the incorrect afm and not the proper one. I will go through the diagnostic sheet again to make sure that it isn’t another underlying issue.
OK, if the CEL illuminates with 1 of the 3 AFMs and doesn't illuminate with the other 2, then the issue is with the 2 AFMs.
You need to verify that they are the correct AFMs for 1988 (FJ62) through 1992 (FJ80) as both models used the same part number (22250-61010). The part number changed in 1993 with the 1FZ-FE engine.
The pinouts for the 2 units are the same, but I've not measured the internal resistances between the 2 to make a valid comparison.
The OEM unit 22250-61010 has been out of production for at least the last 15 years, so anything you're getting is aftermarket or a refurbished unit. There are test procedures in the Toyota FSM to verify that the AFM is within spec. I would be testing them before installation.
I would also be searching the classified section for vehicles getting parted out and try to find a used OEM unit.
There are older threads on replacing the 3FE AFM with one from a specific year Camry which might be easier to source.
**********DO NOT REMOVE THE 2 PHILLIPS SCREWS ON THE AFM CONNECTOR. THIS WILL DAMAGE THE INTERNAL WIRING.**********
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- Thread starter
- #9
Ok, the two AFM I have purchased, one of them is the correct one for the 91 FJ80. I sourced the same part number you provided to ensure I was buying the correct one. Bolts and seals right up, but the LC won't read it and therefore has no CEL, so no start. The other AFM I have used is from the specific Camry model you mentioned, which I believe was the 1993 model. It fits perfectly, just like the other, but with the same result: no CEL, no start. I also ran across this testing dialogue from the FSM, and they both are good. That's why I am stumped on why it won't read it, but reads the one that shouldn't be on there?
Have you tested the one that came on the truck according to the FSM?
I'm wondering if the previous owner changed the wiring on the connector to match the AFM that he put on.
If you have the EWD, you should be able to verify the wiring back to the ECU.
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Yes, I tested that one as well and found it to be good. I just confirmed that it is not an OEM connector, but it has seven white wires that are probably just connected to the harness's wires, whichever way. Would this cause the LC not to read it, as it may not be wired correctly to the specific pins that it's supposed to go to? I also don't have the EWD. I have been trying to find information on this particular wiring in this part of the harness.
ppc
M Go Blue
@ASUAREZ27
The Electrical Wiring Diagrams (EWD) can be found in the "Resources" section of this forum.
You need to realize that a 90's era vehicle is totally different from modern vehicles. Your statement "Would this cause the LC not to read it" is not correct. In modern vehicles, electrical components are connected/communicate together via a CAN bus or other digital standard where the term "read" is appropriate. In early to mid 90's nothing is connected to the bus. Each sensor connects to the ECM, relay or other device via an analog signal. There is no protocol of data transferred back and forth. That makes it relatively easy to step through each connection using the EWD and FSM to determine the problem.
Your current method of throwing parts at the problem is going to be expensive and frustrating.
The Electrical Wiring Diagrams (EWD) can be found in the "Resources" section of this forum.
You need to realize that a 90's era vehicle is totally different from modern vehicles. Your statement "Would this cause the LC not to read it" is not correct. In modern vehicles, electrical components are connected/communicate together via a CAN bus or other digital standard where the term "read" is appropriate. In early to mid 90's nothing is connected to the bus. Each sensor connects to the ECM, relay or other device via an analog signal. There is no protocol of data transferred back and forth. That makes it relatively easy to step through each connection using the EWD and FSM to determine the problem.
Your current method of throwing parts at the problem is going to be expensive and frustrating.
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Without both the FSM and EWD you're blindfolded in a dark room.
If it's not an OEM connector, how did you plug it into the other 2 AFMs?
The connector should look like the one below. Pins w/ pigtail are 82998-12130.
As stated earlier, you should verify the pins back to the ECU.
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Sorry I should’ve worded that better. The connector on the LC currently is the correct connector it’s just not original to the vehicle and seems as it was changed at some point in time. The pigtails that this connector has are all white, so I’m sure the previous owner just wired it up however they thought since I’m sure it didn’t come with a wiring diagram to follow of some sort.
