3 bar map problems

[pacecarta]

I believe this is not correct, although it is not the cause of the O.P. issue.

try turning the alky off, it may be kicking on too early.

Bob

I believe the info that pacecarta stated about the wiring to be wrong also. The sensor is the same as any of the other 3 bar sensors that GM sold.

this thread is done but dragging it back up
i'm seldom wrong, and remember odd things ive read

this ancient thread popped up and reminded me of where i heard about the reversed wiring of the 3 bar

http://www.turbobuick.com/forums/alcohol-nitrous-propane-tech/96951-3-bar-map-sensor-wiring-faq.html

 

[Razor]

The only sensors that where reversed came from 89 TTA's.. oem ones.

12223861 are all wired the same.

 

[Razor]

This one's for Bob

The only sensors that where reversed came from 89 TTA's.. oem ones.

12223861 are all wired the same.

Look what I found.. this is an OEM boost gauge plug for the 89 TTA. What it has is a 68 ohm resistor on the black wire of the plug. This was done to raise the output voltage on the sensor to calibrate it to the 3 bar. Guess engineering and mfg goofed when they built the cars.

Anyways looking at the male plug. The closest pin is black, furthest is gray. Green is center. Wired just like a TPS.

So on a TTA.. you would need this plug pictured to "zero" out your boost gauge.. then need the GM adapter plug to reverse its polarity.