go'in crazy

My manual tells me the procedure for a map that is mounted on the firewall. Mine is mounted on the throttle body. So there is no hose.I'm getting a code 5,and the idle is pulsing. Any advice would be appreciated.

slowcivic2k

I would first ensure that you have no vacuum leaks. Leaks cause all kinds of crazy things to happen, especially at idle. Generally speaking, a MAP sensor will give you problems when the manifold vacuum changes drastically, (from 20inHG at idle, to 5-8inHG on takeoff, and 1inHG or 0 at WOT.) by the way it sounds, you have a vacuum leak.

Testing that sensor will require it to be unbolted and a hand-held vacuum pump be attached to the port. To do this test the key needs to be in the ON (II) position and a voltmeter attached in parallel to the S or Signal Terminal on the sensor. Some of them have the pinout on the sensor, some of them don't.

Former User

Start by removing the MAP sensor from the throttle body and cleaning it and its port leading from the throttle body. If they're gunked up, consider cleaning the IACV and FITV on the throttle body as well.

go'in crazy

I've checked over hoses and all appears o.k. Removed sensor,it is clean. I don't have a vacuum pump yet, but to back it up a bit, I didn't mention earlier that when checking voltage on the connector,yellow/red to ground gave me 4/5 volts,white to ground shows 0. Is this indicative of anything?

Former User

What's the voltage between the Wht wire and Grn/Wht wire?

go'in crazy

I tested between the yellow/red and green/white(assuming that was ground) and got4/5 volts, got 0 between the white and green/white.

Former User

There should be ~5V between the Wht and Grn/Wht wires. Check for an open in the Wht wire between the ECU connector and MAP sensor connectors.