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Discussion Starter · #1 ·
I think I've got a problem with my AFM on an '83 ZX. I haven't broken out the ohmmeter yet to check it-I want to wait for warmer weather. The car sputters under mild to moderate acceleration -- but is fine at full throttle or at idle. Does this sound like an AFM problem? Based on previous postings, this is my guess. So, I have the following question - can the AFM be adjusted? If so, I would plan to try the trial and error approach unless someone here has a better idea -- the Haynes manual doesn't state how to adjust or even that it is adjustable.

If I end up needed to replace the AFM, does anyone know if the ones sold by Victoria British or Motorsport need adjustment after installed?

Thanks
 

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Discussion Starter · #2 ·
> I think I've got a problem with my AFM on an
> '83 ZX. I haven't broken out the ohmmeter
> yet to check it-I want to wait for warmer
> weather. The car sputters under mild to
> moderate acceleration -- but is fine at full
> throttle or at idle. Does this sound like an
> AFM problem? Based on previous postings,
> this is my guess. So, I have the following
> question - can the AFM be adjusted? If so, I
> would plan to try the trial and error
> approach unless someone here has a better
> idea -- the Haynes manual doesn't state how
> to adjust or even that it is adjustable.

> If I end up needed to replace the AFM, does
> anyone know if the ones sold by Victoria
> British or Motorsport need adjustment after
> installed?

> Thanks
The AFM is adjustable. I could be wrong but I dont think that is your problem. Check the throttle position sensor first. that is the small black covered sensor on the drivers side of the throttle body. To adjust the AFM pop off the black cover,(have some silicone sealant on hand to seal it back up when you are done). Get a small black marker and put a line on both sides of the screw that holds down the white plastic ring gear. take a phillips screwdriver and loosen that screw WHILE HOLDING the ring gear with another finger. Moving the gear a few teeth counterclockwise will loosen the tension on the AFM flap thereby alowing more air in sooner. The computer will compensate for this adjustment and give enough gas to do the job. This little trick only helps the low end as the flap inside the meter will already be open all the way at wide open throttle. Do this adjustment while the car is running so you can hear how far you can adjust it without making it stall. If moved about 5 teeth, the car will sound as though a lumpy cam is in the car at idle. once gas is pressed it sounds normal. At this point you can really feel the responsivness by the seat of your pants. 5 teeth is a little to much for every day driving because it will idle too low. 3 teeth is just fine overall. Oh yeah, DONT let go of the ring gear when the screw is loose. But then again, that is why you mark it first before losening the screw.
 

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Discussion Starter · #3 ·
Tthanks for the info on adjusting the AFM, I will keep this for future reference, but it sounds like you think I might have a problem with the throttle position sensor. I will check my Haynes manual to see if it talks about how to check the sensor, but in case it does not, how would you recommend I check it? What specifically am I checking for? adjustment or failure? I appreciate any insight you can provide.

Additionally, would you recommend that I go ahead and make adjustments to the AFM, as per your instructions? What's the down side of doing this? My Haynes manual doesn't talk much about the AFM. I know that it regulates air flow into the EFI, but beyond that it's black magic to me.

Thanks for the suggestion.
 
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