Hi,

The check engine light has been lighting up with a code MAP LO 34. I have a log file of when the problem occurs.

It usually happens after I take off for a bit and seems to be shortly after the engine has warmed up and running in closed loop. I'd be driving on the road then I'd get a sudden jerking of the engine for a few second then I carry on with the SES light on. It might stay or disappear after a while.

The MAP reading is not moving on the WUD page either..

MAP: 0 Cnt's
10.4.KPa
0.0 Volts

So, what's going on? A bad MAP sensor? I have a working spare I can swap.

 

Check the MAP connector, a MAP low will occur if the signal is lost going to the ECM, or if the +5 volts to the MAP is lost.

Can also do things such as key-on, engine-off, and while observing the Diagnostic display wiggle the connector and tap on the MAP sensor.

RBob.

 

Thanks, didn't spend a bunch of time troubleshooting with the problem MAP sensor. I just shoved the spare in there and all seemed well so far.