Starts and runs with MAF sensor unplugged code p102

RB HENSON

MEMBER
1997 VOLVO 850
2.4L
5 CYL
130,000 MILES

My car listed above GLT model, start and runs then stops. I unplugged the MAF sensor and it restarts. When I plug it back in it shuts off. I cleaned it after that it gives me a p102 code says MAF sensor problem. What do you think?

Monday, July 23rd, 2018 AT 12:10 PM

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,173 POSTS

Hi and thanks for using 2CarPros.com.

That code indicates a weak signal from the MAF. There is a good chance a connection is corroded or loose, or the sensor itself is bad. Here is a link which describes the process of cleaning one. Check through it to see if you missed anything.

https://www.2carpros.com/articles/mass-air-flow-service

Next, here are the directions from alldata to test the sensor. The attached pictures correlate with these directions.

CHECKING MASS AIR FLOW SENSOR

Condition

- Diagnostic Trouble Codes (DTCs) in Motronic 4.4 absent.
- Diagnostic trouble codes (DTCs) in AW 50-42 absent.
- Engine at normal operating temperature.
- The fault is permanent.
Possible Source
- Blocked Air Cleaner (ACL) or air intake.
Checking Air Intake
- Check air intake in front of the radiator, air duct, air cleaner (ACL) housing and air cleaner insert for signs of blockage (leaves, paper etc).
Is there any blockage?

Yes:
- Remedy blockage as necessary.

No:
- Proceed to test step below.

Checking Mass Air Flow Sensor

- Ignition ON.
- Mass Air Flow (MAF) Sensor connected.
- Connect a voltmeter between mass air flow (MAF) sensor connector terminals 2 and 4.

Voltmeter should read 0.1 - 0.2 Volts.
If reading is OK:
- Proceed to Checking Ignition Cables, Distributor Cap and Rotor section.
If reading is incorrect:
- Fault-trace mass air flow (MAF) sensor.

I hope this is helpful. Let me know if you have other questions.

Take care,
Joe

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