Need H_elp with an 89 MPFI 2.8 V6 (Need MAF...)

Kurek, Larry lkurek at anl.gov
Mon Jan 4 16:07:15 GMT 1999


Guys:

I am having a slight problem with the 2.8 MPFI motor I put in my S10 in
place of the old carb motor with the hole in the side of the block :)

I was driving home last night and it started cuting out at anything between
off idle to about half throttle...kind of like it was running out of gas,
but it wasn't since I JUST filled up the tank. The fuel pump is new, and is
getting great pressure, so I don't think it is a fuel problem. However...the
motor seemed to fix itself and run great again. No SES light either. Once I
got home, I decided to check the obvious....coil connectors, wires, etc
etc...all seemed fine. However, after a quick test drive, I popped the hood
and it almost died out on me.. came back, and set an SES light...code 34,
low MAF reading. So, I backprobed the MAF connector and all was OK, I
checked for any loose connections and didn't see any either, so i reset the
ECM and it seemed OK. Well, on the drive to work this morning, same damn
thing. Again, a code 34. One of the causes for this code is a leak between
the MAF and the throttle body. I checked this as well, and the only thing
that MAY be a problem, is the temperature sensor bung I siliconed into the
elbow. The silicone looks to have pulled back just a bit and there may be a
SLIGHT opening into the elbow. Could this be enough to cause a problem? I
can't emphasize enough how small of a leak this may be. Are these MAF
sensors that sensitive? FWIW, I am also running an open element K&N filter,
and it has recently gotten quite cold here (Chicago area). 

Sooo....any ideas?  How do I go about testing the MAF itself? Like I
mentioned above...the connector checks out fine with +B, ground, and +5v. 

Does anyone have a spare MAF that they would be willing to part with? This
is a three wire MAF out of an 89 Camaro 2.8 V6. It isn't the hot wire
variety, but seems to use a thermistor instead?

Finally, I did note that the lights on the car dim on occasion for a few
seconds at a time. Could this be a bad alternator? Could this cause the
problems with the MAF? I'm stretching here guys...I don't want to get
stranded in sub-zero temperatures in the middle of nowhere...

Thanks!


Larry



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