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I posted a msg below about having problems when trying to go over 4
psi of boost, I checked most sensors and ground and they are fine
except the AFM.

I am using as a reference (I dont have the Shop manual yet) the Bosch
Fuel Injection and Engine Management book. It doesnt state specific
resitances. Let me quote the book on the troubleshooting the AFM
Test the air-flow sensor insulation. With the ignition off,
disconnect the air-flow sensor wiring connector. Connect one lead of
an ohm meter to ground on the chassis and touch each air-flow sensor
terminal with the other lead as shown. A reading other than infinite
ohms (no continuity) indicates a faulty air-flow sensor

I did the test and it gives me continuity on the common terminal that
goes to the air temp sensor and the resistance track.
****! (well, I am hoping the book is wrong)

Also, I performed the following test
Check the sensor resistance track. Identify the correct terminals
for resistance track input and output and connect an ohmmeter across
them. The resistance should change as the air vane opens. The
actual values are less important that the fact that the values change
smoothly, without any sudden drop outs.

I removed the AFM square cap and put the ohmmeter in the proper wires
and moved the vane smoothly and the last thing I get is smooth
variation of the resistance it changes erratically from 180 ohms to
infinity to 300 and keep doing it all the way.
Is is trashed? I know it should be. I am getting a friends unit to
test it.

What shocks me is the fact that when I was working with the new
compressor I only disconnected the unit and to say more I even used
the car and worked fine except when hard shifting when the ignition
just disapeared.
Still with that ignition problem which I didnt knew at that moment
that it was the coil, I broke the differential and swapped in an
LSD.
A couple of weeks (about 5) passed before I replaced the diff.
When testing the diff the the coil died and at the same time I noticed
I was having problems with a loose i/c connection, so I replaced the
coil and used the HKS piping I had.
The day I was testing the diff, the car had the same symptoms it is
having now

My suspicion is on the time the car was just sitting there and maybe
the AFM got wet or something...

One question....
some already know that coil wires can be inverted but maybe the
performance is not the same. Is the black white-stripped wire the
one that goes to the coil (-)?

If you are still reading, thanks for the interest...
and if you reply... better!

thanks,

CarlosZXT
 

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> I posted a msg below about having problems
> when trying to go over 4
> psi of boost, I checked most sensors and
> ground and they are fine
> except the AFM.

> I am using as a reference (I dont have the
> Shop manual yet) the Bosch
> Fuel Injection and Engine Management book.
> It doesnt state specific
> resitances. Let me quote the book on the
> troubleshooting the AFM
> Test the air-flow sensor insulation.
> With the ignition off,
> disconnect the air-flow sensor wiring
> connector. Connect one lead of
> an ohm meter to ground on the chassis and
> touch each air-flow sensor
> terminal with the other lead as shown. A
> reading other than infinite
> ohms (no continuity) indicates a faulty
> air-flow sensor

> I did the test and it gives me continuity on
> the common terminal that
> goes to the air temp sensor and the
> resistance track.
> ****! (well, I am hoping the book is wrong)

> Also, I performed the following test
> Check the sensor resistance track.
> Identify the correct terminals
> for resistance track input and output and
> connect an ohmmeter across
> them. The resistance should change as the
> air vane opens. The
> actual values are less important that the
> fact that the values change
> smoothly, without any sudden drop
> outs.

> I removed the AFM square cap and put the
> ohmmeter in the proper wires
> and moved the vane smoothly and the last
> thing I get is smooth
> variation of the resistance it changes
> erratically from 180 ohms to
> infinity to 300 and keep doing it all the
> way.
> Is is trashed? I know it should be. I am
> getting a friends unit to
> test it.

> What shocks me is the fact that when I was
> working with the new
> compressor I only disconnected the unit and
> to say more I even used
> the car and worked fine except when hard
> shifting when the ignition
> just disapeared.
> Still with that ignition problem which I
> didnt knew at that moment
> that it was the coil, I broke the
> differential and swapped in an
> LSD.
> A couple of weeks (about 5) passed before I
> replaced the diff.
> When testing the diff the the coil died and
> at the same time I noticed
> I was having problems with a loose i/c
> connection, so I replaced the
> coil and used the HKS piping I had.
> The day I was testing the diff, the car had
> the same symptoms it is
> having now

> My suspicion is on the time the car was just
> sitting there and maybe
> the AFM got wet or something...

> One question....
> some already know that coil wires can be
> inverted but maybe the
> performance is not the same. Is the black
> white-stripped wire the
> one that goes to the coil (-)?

> If you are still reading, thanks for the
> interest...
> and if you reply... better!

> thanks,

> CarlosZXT

Hey Carlos- It is my understanding that if when the vane is opened it should provide a smooth and increasing resistance. If it doesn't it is bad....not saying that this is *THE* problem, but certainly is *a* problem. Discovered the same thing on my AFM when I checked it to give another guy some readings, damned if mine wasn't bad too! Car produces more power than it use to because it is getting the right amount of fuel now, mine is an '82 L28 Non -turbo.

Ken
 
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