99blackout

well my light came on after i had a new clutch and exhaust put on...and i scanned it and came up with the code P1151 ( Manufacturer Contrl Fuel Air Metering)...so i had my MAF replace and also had the codes reset...well its came back on a day or 2 later....any guesses what could be wrong?

96mod289

could it be your exhaust. do you have cats?

99gtstang

Mines come on about every 800 miles... for the cats p 0420 i think i finally bought a scanner to shut it off. If no cats dont get BBK mils. there worthless

rbstang

p1151 is an o2 sensor reading lean.

P1151
A Heated Exhaust Oxygen (HO2S) sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when the fuel control system no longer detects switching for a calibrated amount of time.

Problems that cause this:
Exhaust leaks before or near the HO2S(s)
Air leaks after the MAF
Vacuum Leaks
Damaged 02s
Short to VPWR in the harness or HO2S
Water in the harness connector
Open/shorted HO2S circuit
Corrosion or poor mating terminals and wiring
Leaking gasket
Stuck EGR valve

im gonna go ahead and say your 02 sensor is bad or you replace your passenger side gasket when you got a new midpipe and its leaking.

Str33tGunner28

could just be your exhaust messing with the 02 sensors. when my exhaust was put on, the check engine soon light popped on 24/7 365. i just let it stay on.

GolfmanSpeck

I just got this code in my 1998 gt. I just put the cats on (formally a off-road h-pipe) to have the car smogged. It passed but now i have this error code. Do you think there is a leak from the pipes?