Symptoms of bad maf sensor?

**LS1junkie18** · 02-17-2010, 12:44 PM

my 98 ss brought up the evaporative emissions code...unplugged the maf sensor and it seemed to make things alot better...what does this mean?

**0rion** · 02-17-2010, 02:46 PM

your evap has no correlation to your maf. Any mods to the car? When was the last time you cleaned your maf sensor?

**TransAm11973** · 02-17-2010, 03:32 PM

you have a fuel system issue, with the evap canister system for the fuel tank

**KMdef9** · 02-17-2010, 03:46 PM

What code number is it?

**LS1junkie18** · 02-17-2010, 07:59 PM

Never cleaned the maf...should i try that or just replace it?...and how would i find the exact problem with the evap system?

**95camaroZNC** · 02-17-2010, 09:54 PM

Clean the maf a bottle of the stuff is 5 bucks at a auto store if that doesn't fix it continue to the next thing.

**Cutlass** · 02-18-2010, 03:49 AM

Originally Posted by LS1junkie18

and how would i find the exact problem with the evap system?

Post the code number and we'll tell you.

**PFM** · 02-18-2010, 06:28 AM

Are you sure you just don't have a bad gas tank cap. I know if its loose or not sealing correctly it will throw that code. A bad or dirty MAF usually causes motor surging and Idle problems on my car.

**TransAm11973** · 02-19-2010, 02:47 PM

does it say if its with the fuel system?
maybe your MAF was dirty anyway.....

**LS1junkie18** · 02-22-2010, 02:01 PM

checked the codes today and its bringing up P0102, P0157, and P0449...low input and low voltage i believe...Thanks for any help.

**LS1junkie18** · 02-22-2010, 02:06 PM

1998 SS M6...brought up codes p0157 and p0102...any help with exactly wat the problem would be is appreciated.

**Smittro** · 02-22-2010, 02:21 PM

From my manual:

P0102= Mass air flow sensor circuit, low input
P0157= O2 sensor curcuit, low voltage post converter right bank..

**Hi-Po** · 02-22-2010, 02:33 PM

P0102 is the the code that needs to be addressed first. This is an indication you MAF has failed. Is it a factory MAF or aftermarket?

Check this thread out for P0157:

http://www.ls1.com/forums/showthread...highlight=code

**LS1junkie18** · 02-22-2010, 02:56 PM

Its factory maf

**35th-ANV-SS** · 02-22-2010, 04:10 PM

You can usually do a quick check of the MAF by tapping on the flat portion of the sensor body with a screwdriver while the car is running. If the engine stumbles or stalls, the sensor is faulty.

You can also check voltage with the ignition key turned to the on position, car not running. Check the voltage on terminal B ground (black/white) and terminal A (yellow). There should be between 4-6 volts .

Last, you can check the battery voltage to the MAF with the ignition key turned to the on position, car not running across terminals B ground (black/white) and terminal C (pink). Should read 12 volts.

This is from the Haynes manual for pre-1998 V8's.