Welcome Guest [Log In] [Register]
Posted ImageWelcome to the all new Geo Metro Forum. We hope you enjoy your visit.

You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are features you can't use and images you can't see. Registration is simple, fast, and completely free. If you're already a member please log in to your account to access all of our features:

Join our community!




Username:   Password:
Add Reply
Won't run; Metro won't run w/ vacuum line attached to MAP sensor
Topic Started: Aug 2 2012, 08:33 PM (418 Views)
nickcoop82
Fresh Fish
[ * ]
So here we go. I have a 1991 Metro XFi. The only way I can get it to just idle, is to pull the vacuum line for the MAP sensor. When the MAP sensor vacuum line is connected, the engine seems to flood and then dies. I can keep it running by pumping the gas, but the exhaust smells really rich. I'm sure its something very simple, but I don't know where to start. :banghead Any suggestions would be awesome.
Offline Profile Quote Post Goto Top
 
mwebb
Member Avatar
FOG

three pins on the MAP sensor

one is supposed to be zero volts relative to the battery negative , the other end should be 5 volts relative to battery negative
the center should be about 4.5 volts key on engine off and as vacuum increases on the vacuum port of the MAP sensor voltage should get closer to 1 volt

test the MAP sensor circuit to see if yours is showing those voltages
use T pins to test the MAP sensor while it is connected
see T pins in the electrical section of this forum

the 0 and 5 volt pins must be just that , within 50mv relative to battery negative
Offline Profile Quote Post Goto Top
 
Memphis metro


Engine ever been rebuilt? Start with right things right first. Do a engine compression test. If the compression is within specifications, tune it up with new spark plugs and wires and distributor cap and rotor. Then proceed to find after knowing these things are right why the car will not idle correctly if the idle problem still persist.

Quit unplugging the map sensor, this will make it run rich. After reconnecting your map sensor connections and leaving them alone, disconnect your negative battery cable for ten seconds and reconnect it then drive the car for a while and see if the check engine light comes on. If it does, find what the codes are and post them here. Before you do any of that, do the engine compression test and the tune up.

Welcome to geometroforum.
Offline Profile Quote Post Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
« Previous Topic · Engine Tech & Diagnostics · Next Topic »
Add Reply