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So, I've had an interesting week or so.

When my car was started from stone cold; it had no issues. I could drive to work, leave the car all day, then drive home again.

If I stopped fill up, or go & do some shopping, then restarted the car; initially, it would randomly stall at idle, and throw a CEL code; P0100, which is the AFM. It did it once, then not again for several days. Reset code; no issues.

If restarted, the car would drive normally. Progressively over a week or so, it would stall more regularly on a hot restart.

Then t would throw the light immediately at hot start, and when you accelerated, it would get to 2200rpm, and start stuttering as if the AFM was disconnected.
After a few minutes of driving it would behave as normal.

I replaced a very dirty air filter, but no real change.

Cleaned AFM; no change.

It occurred to me, that on my Informeter; if the intake temp was above approx 35-40 deg; the problem would manifest, and it started doing the same thing if driven in traffic, and the Intake temp rose to the set level.

Eventually, the CEL would not reset, but as long as the Intake temp was around ambient or below 35 deg, the car would drive perfectly.

Replaced AFM with the spare I had from Scotty (for just such an occasion) reset CEL; issue hasn't reoccurred.

Very strange.

Can anyone with an Informeter tell me what their AFM reads when the engine is NOT started? Just with the key in the ON position?

Mine is roughly 1.02v even before being started. Settles around 1.47-1.50 at idle.

Cheers guys, hope this helps someone. I've never seen an AFM fail in such an unusual and random fashion.

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https://www.sau.com.au/forums/topic/446016-nm35-stagea-afm-fault/
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Yep, it sounds about right at 1v. The afm can actually read reverse airflow down to 0v.

Hey mate, thanks for that. :worship:

Can you put me on the list for a replacement when you have some? I'll forward some cash to you in the next couple of days. ;)

I have plenty mate, can you try out my new site for me? I want to check it works.

http://scottyscustoms.com.au/product-category/m35-stagea/

Looks to be working fine mate. :yes:

Nice looking site !

Looks to be working fine mate. :yes:

Nice looking site !

Thanks. A customer did some bartering with me. :)

Mobile friendly, shopping cart, built in postage calculator. Now I have to find the time to insert all the product data. :/

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Thanks. A customer did some bartering with me. :)

Mobile friendly, shopping cart, built in postage calculator. Now I have to find the time to insert all the product data. :/

Looks good scotty.. simple and it works. Needs more M35

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