Stalling when revved

mk3_manny

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#1
I took out my VAF/MAF sensor to clean it (with the right cleaner), when i went to plug it back in, the car wouldnt start. i realize my wiring on my sensor was loose so i rewired. The car now starts and has a fairly good idle, but when revved up engine stalls out. If accelerated at a constant speed its fine, but when its revved it simply looses all power and stalls. Last time i revved it, smoke came out close to where the turbo is located. Do you guys have any suggestions? (7mgte in an 89).
 

shadowman1977

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#2
Hey man, I’m having a similar issue. Try disconnecting the TPS and see if it still happens. If it doesn’t, try recalibrating your TPS. That may help.
 

Piratetip

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#6
If its the stock maf its completely sealed as its a vortex street style sensor
The stock karman vortex sensor is not totally sealed.
There is a pressure directing hole or path from where the oscillating vorticies are generated up to the small mirror and photo transistor.

If you clean the sensor with any product other than what pi mentioned above you will risk contaminating the mirror / photo transistor.
 

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3p141592654

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#13
code 31 is probably a wiring or connector problem with the AFM. It could also be a bad AFM sensor.
Car will run badly in limp mode with code 31. Needs to be fixed.

don't worry about code 51. Could be TPS not calibrated, or just the AC left on.
 
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shadowman1977

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#14
The stock karman vortex sensor is not totally sealed.
There is a pressure directing hole or path from where the oscillating vorticies are generated up to the small mirror and photo transistor.

If you clean the sensor with any product other than what pi mentioned above you will risk contaminating the mirror / photo transistor.
I thought it was sealed, my bad. I may very well have damaged mine also. Think I used brake clean assuming it was a sealed unit with a photo sensor like a cad cell eye on a furnace.
:(
 
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#15
code 31 is probably a wiring or connector problem with the AFM. It could also be a bad AFM sensor.
Car will run badly in limp mode with code 31. Needs to be fixed.

don't worry about code 51. Could be TPS not calibrated, or just the AC left on.
every diagram i found was the same, i replicated that, the only thing where i mightve messed up is by mixing up the brown wires
 

shadowman1977

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#16
I thought it was sealed, my bad. I may very well have damaged mine also. Think I used brake clean assuming it was a sealed unit with a photo sensor like a cad cell eye on a furnace.
:(
Just checked mine today apparently the other protrusion from the sensor is broken. Probably why I can’t get the RPM’s up without stalling on the way down FML!!! :(