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R34 Gtt Blown Afm?

FLN75S

By FLN75S,
in Engines & Forced Induction

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FLN75S Mentor

FLN75S

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Posted

Just after your ideas on this and if you have experianced this problem before.

Was out on the weekend when my mates R34 GTT suddenly lost all power. I was behind him in my 34 when it happened and i immedietly noticed black smoke coming out the exhaust.

i assumed it was a blown cooler pipe but after checking them and looking for any other leaks we could not get it to run.

I then tried unplugging the AFM as this was my next guess and it suddenly would run but when driven not rev past about 2500rpm.

Am i right in saying the AFM has blown and by unplugging it the car has gone into limp mode (i noticed the engine check light is on once this is unplugged)?

The car was on light throttle when this happened at about 45km/h.

I had a bit of a search around but couldnt find any problems exactly like this so any help would be greatly appreciated oh and yes i have pulled the AFM apart and the soldering looks perfect.

Thanks in advance.

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James_03 Mentor

James_03

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Posted (edited)

Early 32's are more prone to dry solder joints then 34's.

Put the ECU into diagnostic mode and check for an AFM error code. Should flash the code back if it's bad. That's if your still using factory management.

You can check the resistance values between the pins to give you an idea if it's bad. Could simply be a dirty AFM wire. But yes I would say it fell back into limp mode when you removed the AFM hence it was able to start.

Edited by James_03
FLN75S Mentor

FLN75S

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Early 32's are more prone to dry solder joints then 34's.

Put the ECU into diagnostic mode and check for an AFM error code. Should flash the code back if it's bad. That's if your still using factory management.

You can check the resistance values between the pins to give you an idea if it's bad. Could simply be a dirty AFM wire. But yes I would say it fell back into limp mode.

Forgot to mention that car is standard with FMIC and full exhaust.

I will Do the diagnostics test and clean out the AFM and see how that goes thanks for your help.

FLN75S Mentor

FLN75S

Posted
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Posted
Yeah see what you get after diags. Just be careful what you use to clean the AFM with.

Most people use a carby cleaner spray which is what I recommend.

I have heard of ppl using all sorts of shit, lemon juice etc lol.

Haha yeh i've heard a few good ones myself but lemon juice is a new one lol.

thanks for ya help.

allthewaytotheskyline Mentor

allthewaytotheskyline

Posted
Posted

i highly recommend you dont use anything other then "electrical contact cleaner" it will automatically dry and clean once applied it is used for electrical boards and components.

there will be a residue left on the afm if you use anything else.

Bass

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