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Code 49 - 1990 AFM and IAC wiring help?

lanigan_vanagon
 

Hi all,
During a recent long roadtrip in my (previously well-running) 1990 EJ22 automatic conversion, some serious hesitation, stumbling, and stalling began. It seems to happen pretty randomly, infrequently at first and may have gotten worse in the past few days.

Code 49 appeared after the first stall, and I tried cleaning the AFM with carb cleaner then some other things that were probably needed anyway (new plugs and leads, new fuel pump and filters, found and fixed some small potential vacuum and intake air leaks, etc). But I still have the symptoms, so I'm back to focusing on the AFM...

*Question 1: Can someone tell me how to test voltage the 5 ports on the AFM connector? What I think is the ground is reading .018 ohms to ground, is that too high?

Also considering the IAC. I noticed that my IAC connector has 3 ports (the middle reads 12v) but the IAC itself only has 2 outer pins (no middle!).

*Question 2: Could it be that I have the wrong IAC for my set-up? Could this lead to rich-running and gunking up the engine, causing my stumbling/ stalling?

Here's the numbers as I know them:
Engine: 1990 ej22 from a manual legacy (now in automatic Vanagon)
ECU: AA562
AFM: AA170
IAC: 2-pin (don't know the number)

Thanks for any help!
Joseph
 

Something simple to check is the connectors to the engine harness. I had similar symptoms on my SVX powered Westy. I couldn't figure it out and paid (a lot) to have a shop diagnose it. After replacing a lot of parts, they finally found the engine harness connectors were not properly snapped together.

On May 20, 2012, at 2:23 AM, lanigan_vanagon wrote:

Hi all,
During a recent long roadtrip in my (previously well-running) 1990 EJ22 automatic conversion, some serious hesitation, stumbling, and stalling began. It seems to happen pretty randomly, infrequently at first and may have gotten worse in the past few days.

Code 49 appeared after the first stall, and I tried cleaning the AFM with carb cleaner then some other things that were probably needed anyway (new plugs and leads, new fuel pump and filters, found and fixed some small potential vacuum and intake air leaks, etc). But I still have the symptoms, so I'm back to focusing on the AFM...

*Question 1: Can someone tell me how to test voltage the 5 ports on the AFM connector? What I think is the ground is reading .018 ohms to ground, is that too high?

Also considering the IAC. I noticed that my IAC connector has 3 ports (the middle reads 12v) but the IAC itself only has 2 outer pins (no middle!).

*Question 2: Could it be that I have the wrong IAC for my set-up? Could this lead to rich-running and gunking up the engine, causing my stumbling/ stalling?
 

Good morning Joseph,
Your ECU, MAFM and IAC are the correct matched set that came from a manual tranny donor - so that can not be your problem.

Try Kim's suggestion - use some good contact cleaner - and let us know what you find.

Tom
Burlington ON

--- In subaruvanagon@..., "lanigan_vanagon" <ej.lanigan@...> wrote:

Hi all,
During a recent long roadtrip in my (previously well-running) 1990 EJ22 automatic conversion, some serious hesitation, stumbling, and stalling began. It seems to happen pretty randomly, infrequently at first and may have gotten worse in the past few days.

Code 49 appeared after the first stall, and I tried cleaning the AFM with carb cleaner then some other things that were probably needed anyway (new plugs and leads, new fuel pump and filters, found and fixed some small potential vacuum and intake air leaks, etc). But I still have the symptoms, so I'm back to focusing on the AFM...

*Question 1: Can someone tell me how to test voltage the 5 ports on the AFM connector? What I think is the ground is reading .018 ohms to ground, is that too high?

Also considering the IAC. I noticed that my IAC connector has 3 ports (the middle reads 12v) but the IAC itself only has 2 outer pins (no middle!).

*Question 2: Could it be that I have the wrong IAC for my set-up? Could this lead to rich-running and gunking up the engine, causing my stumbling/ stalling?

Here's the numbers as I know them:
Engine: 1990 ej22 from a manual legacy (now in automatic Vanagon)
ECU: AA562
AFM: AA170
IAC: 2-pin (don't know the number)

Thanks for any help!
Joseph
lanigan_vanagon
 

Thanks Tom for the context - and thanks Kim, that is a brilliant suggestion- I made sure they are snapped on tight...

I just took a test-run to the bike shop and it stalled 3 times in under 2 miles! Necessity is also the mother of focused diagnosis, so I turned once again to the AFM connector plug. This time, I couldn't find a ground at the black/red center wire - No ground at all! So I rigged up a quick fix and Vroom - I made it home!

I'm hoping this was the problem all along - though I will feel dumb for not ruling this out first. I had a mysterious problem a few years back that Scott Daniels helped me diagnose as the fuel injector ground. I should have remembered the lesson to ALWAYS CHECK YOUR GROUNDS!!!

In the next few days I'll take another test drive to confirm, and will post the results for posterity.

Thanks again!
Joseph
Portland, OR
1985 Vanagon ASI w/ 1990 ej22

--- In subaruvanagon@..., "Tom Shiels" <tom@...> wrote:

Good morning Joseph,
Your ECU, MAFM and IAC are the correct matched set that came from a manual tranny donor - so that can not be your problem.

Try Kim's suggestion - use some good contact cleaner - and let us know what you find.

Tom
Burlington ON


--- In subaruvanagon@..., "lanigan_vanagon" <ej.lanigan@> wrote:

Hi all,
During a recent long roadtrip in my (previously well-running) 1990 EJ22 automatic conversion, some serious hesitation, stumbling, and stalling began. It seems to happen pretty randomly, infrequently at first and may have gotten worse in the past few days.

Code 49 appeared after the first stall, and I tried cleaning the AFM with carb cleaner then some other things that were probably needed anyway (new plugs and leads, new fuel pump and filters, found and fixed some small potential vacuum and intake air leaks, etc). But I still have the symptoms, so I'm back to focusing on the AFM...

*Question 1: Can someone tell me how to test voltage the 5 ports on the AFM connector? What I think is the ground is reading .018 ohms to ground, is that too high?

Also considering the IAC. I noticed that my IAC connector has 3 ports (the middle reads 12v) but the IAC itself only has 2 outer pins (no middle!).

*Question 2: Could it be that I have the wrong IAC for my set-up? Could this lead to rich-running and gunking up the engine, causing my stumbling/ stalling?

Here's the numbers as I know them:
Engine: 1990 ej22 from a manual legacy (now in automatic Vanagon)
ECU: AA562
AFM: AA170
IAC: 2-pin (don't know the number)

Thanks for any help!
Joseph

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