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Discussion Starter #1
My 82 280ZX turbo seems have a little hesitation, not at full throttle, but the first three shifts; first to second, second to third. When the turbo kicks in, the car seems to have power. No problem going up hills.

I check the resistance of my AFM, should be zero to infinity, but reads 90 ohms climbs to about 600 ohms when flap moves about 1/4 way, drops to about 250 ohms, then climbs again to 600 ohms, then drops again to 250, ect ... it neve goes higher than 600 ohms. Also, occationally, the car is hard to start, cold or warm. All wiring harnesses are new, so is cap, rotor, plugs, wires.
Can AFM contribute to hard start as well?

Thanks for any suggestions.
Chuck
 

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Discussion Starter #2
> My 82 280ZX turbo seems have a little
> hesitation, not at full throttle, but the
> first three shifts; first to second, second
> to third. When the turbo kicks in, the car
> seems to have power. No problem going up
> hills.

> I check the resistance of my AFM, should be
> zero to infinity, but reads 90 ohms climbs
> to about 600 ohms when flap moves about 1/4
> way, drops to about 250 ohms, then climbs
> again to 600 ohms, then drops again to 250,
> ect ... it neve goes higher than 600 ohms.
> Also, occationally, the car is hard to
> start, cold or warm. All wiring harnesses
> are new, so is cap, rotor, plugs, wires.
> Can AFM contribute to hard start as well?

> Thanks for any suggestions.
> Chuck

Hi Chuck

Your AFM seems to be just fine, Ihave tried to measure my own once and i found out that there is no logic to the resistance measurements. My AFM behaves like this:
Closed: 52 Ohm
Quick rise to 350 Ohm
Drop to 300 Ohm
Rise to 400 Ohm etc.

There is a reason why they don't describe the resistance behaveour(bad spelling)- it is simply undescribeable for us deadly to understand, but as far as I have found out the resistance scheme is sole sort of logaritmic, a electronic freak would be able to tell you better, or go to tthe diy_efi pages at

<A HREF=http://efi332.eng.ohio-state.edu/diy_efi>http://efi332.eng.ohio-state.edu/diy_efi</A>

and look under Bosch L-tronic.

Your car is able to start for a half a second or so without movement from the AFM. There is a built in startup system in the control unit that supplies the engine with a predefined amount of fuel for app. half a second, the amount of fuel matches the amount required in idle - so never touch the pedal when you start your engine.
Your problem sounds more likely to be a temperature sensor problem, or even a vac. leak. I'm not very familiar with the emmision control system, because mine is not equipped with any but it seems to give everybody problems so try to get a guy from the US to answer as well.

Best of luck
Brian Madsen
83ZXT
 

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> My 82 280ZX turbo seems have a little
> hesitation, not at full throttle, but the
> first three shifts; first to second, second
> to third. When the turbo kicks in, the car
> seems to have power. No problem going up
> hills.

> I check the resistance of my AFM, should be
> zero to infinity, but reads 90 ohms climbs
> to about 600 ohms when flap moves about 1/4
> way, drops to about 250 ohms, then climbs
> again to 600 ohms, then drops again to 250,
> ect ... it neve goes higher than 600 ohms.
> Also, occationally, the car is hard to
> start, cold or warm. All wiring harnesses
> are new, so is cap, rotor, plugs, wires.
> Can AFM contribute to hard start as well?

> Thanks for any suggestions.
> Chuck

Sounds like the one I just replaced in my 82 NA. Should be linear and progress as the flapper is opened. If it don't, and yours don't, replace it.

Ken
 

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Discussion Starter #4
Pop off the black plastic cover, very carefully, and start the car. Watch the movement. Sometimes the spring tension gets loose. You can tighten it up or loosen it via the set screw inside the cover. Adjust the tension until the car sounds right to you at idle. With the car off, you can spray contact cleaner on the contacts and even carefully bend the contacts to make better contact. Just be gentle with it. When you are done, put some clear silicon around the outside edge of the cover and set it in place. If this doesn't work, throw it in the trash. It worked for me.
 
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