BazH

Where can i purchase a 3 bar map sensor??? low boost is getting me down

Claudius

I suppose RC Developments have them since they fit them on some cars they tune. Xtreme Automobiles should have them as well, and any rally team really since they need to use MAP sensors with ALS.

Mo

You can pick up a cossie 2.5bar MAP sensor for around £20 and they're readily available.

pat

You can get the Weber Marelli APS/05 3 bar map sensor from Demon Tweeks or Burton Power, both places should have them in stock. You will also need a new connector to go onto the MAP sensor. I would suggest that the best thing is to get Ford part number 5028499, listed as a "1990 XR21 throttle pot harness". This connector fits perfectly, is hermetically sealed and also has gold plated contacts. Cost should be about 8 or 9 pounds, and it comes fitted with leads.

You will need to solder the leads onto the existing wiring. If memory serves correctly, there are three wires, colours are red (+5) black (GND) and yellow (signal), or in the case of earlier cars I think the yellow is white... The ford connector has three wires, brown, brown/black and brown/green. If memory serves correctly they should be brown for signal, brown/black for power and brown/green for ground. The pin assignments are a-power, b-ground, c-signal on the APS-05 sensor.

You will need to have an ECU capable of understanding the new transfer function, because the APS05 has a different offset and slope to the original sensor. This pretty much precludes use with the OEM ECU, and probably the Possum Link (the Link 3 bar software was pants last time we used it, hopefully it is better now).

Hope this helps,

Pat.

BazH

I have a Possumlink revision from around Sep 2001 this is for a 93WRX would this be able to cope. Thanks for the replies by the way.