Mass air flow sensor problem

G.A.BECK

MEMBER
1994 BUICK REGAL
3.8L
6 CYL
2WD
AUTOMATIC
220,000 MILES

In the last 3 months I have replaced the Mass air flow sensor 3 times. This a new part not a re-manufactured part, from Delphi. After replacing it. It will last a week or so an the same problem reoccurs. After I drive it for 15 -20 minutes and try to start it again I have to pump the accelerator to get it started. Sometimes that doesn't work, and I have to spray starter fluid in the air intake to finally get it to run. It will still buck some and finally get running. I have no problem starting it first thing in the morning. After It warms up is when the problem occurs. Don't know what else to do. Thanks.

1 Reply

ASEMASTER6371

MECHANIC
52,797 POSTS

Good afternoon,

The first thing I would do is check the fuel pressure. Verify that it is correct.

https://www.2carpros.com/articles/how-to-replace-an-electric-fuel-pump

The pressure should be 40-47 pounds.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

As far as the hard starting, pumping the gas pedal does nothing. The idle air control is what has to be open for the engine breathe and start off every time you start it. This is a common failure for just this issue.

https://www.2carpros.com/articles/how-to-replace-an-idle-speed-control-motor-iac

How did you determine the mass air flow was defective?

https://www.2carpros.com/articles/how-to-replace-a-mass-air-flow-sensor-maf

Roy

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