I know code 34 is MAP low voltage, and i have put my meter on it. Voltage across C and A ( +5v and ground ) is reading right at 5 and holding steady. My meter for some reason won't show me resistance there.

On my MAP I put my meter in across the same two pins and got 1368 Ohms. Does that seem low? Or can I assume my MAP is toast?

87 GT 2.8 auto BTW.

[This message has been edited by EvilSqueezles (edited 07-29-2013).]

Also of note. The car smells as if it runs rich and when I unplug the MAP it dies completely.

Anyone have an idea?

~James

From what I've read with map problems:

Have you tried unplugging it and THEN starting the car? The ECU then creates it's own numbers that would be would be in at least a run-able state?

Do you have any vacuum leaks? If the map isn't getting enough vacuum, it can cause low voltage if I remember correctly

From what I've read, a common vacuum leak shouldn't cause low voltage reading. Would take something rather large, and with the car cold idling at 1500, I doubt that's my problem. I do however need to unplug and then start it and see if that fixes it. I unplugged during idle (which i realize is wrong but I was frustrated). Its out ta gas at the moment since I'm just trying to get it drive able. But I'll do that this weekend and post back.

What you want to do is measure the voltage from the green wire to the black wire.-

You want to do it using back probing. Everything needs to still be connected up, both vacuum and electrical.



Two pins. One in the black, one in the green. When reading voltages on your meter make sure the voltages you are reading are in the .5v - 4.5v range. If the meter is saying mV, that is millivolt and that is way off. Most likely your pins are not touching the metal terminals inside the connector.

The voltages you should get are as such



Start with the key on engine off - you should get about 4.3. Start the engine and it should drop to about 1v at idle. Pop the throttle open and the voltage will jump up, and then when you snap the throttle back it will drop to below the about 1v and then when the engine returns to idle the voltage will return to about 1.

If all this works correctly, you may want to do this same check back probing directly at the ECM.

[This message has been edited by phonedawgz (edited 07-30-2013).]