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Discussion Starter #1
Hello,

Car has been in and out of a 'specialist' 4 times now (in 6 weeks)

each time the emission light shows up after about 50 miles of driving.

all work done includes: Thermostat, Cable in to thermostat, new coolant system, replace top hose (i guess of coolant tank), Engine breather system leak test, new breather valve, breather hose and hose (misc), today I was told the hose coming from the inlet manifold was split so was changed (was called a diaphragm when I asked what part)??

drove it home this evening and again the emission light flicks on. The code registered (told by garage today) is for the mixture i guess its to lean if there's to much air in the system and Lambdas are past maximum adjustment?

My question is: am i being bent over and taken to the cleaners? or could the MAF be to blame, or could the damn emission sensor light be faulty?

spent a grand on the old girl in the last 6 weeks, and I just want it sorted... I hate that damn light.

What you guys reckon? someone please help before I drive it in to the river...
 

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think your being stiffed myself its either a vacuum leak or a dodgy MAF usually, they are milking the job with pointless stuff to me..

unplug the MAF drive it for a while see if the light stays out..will be in limp mode so don't expect full power..
 

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Discussion Starter #3
So vacuum leak should have been taken care of with all the hoses changed etc...?

Silly question but why wouldn't emission light come back on if the MAF is unplugged?

Sent from my HTC Desire using Tapatalk
 

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because then the ECU ignores MAF data which is monitoring the airflow to the engine instead the ECU uses a known set of good fueling parameters preprogrammed into the ECU (limp mode) it runs the engine and disregards the pontential duff data from the MAF which is upsetting the engine fueling..

hence a duff MAF or a vacuum leaks create the same fault duff air info being sent to the engine ECU..

and hence unplugged the ECU does not care if you have a leak the size of your fist its not listening to the MAF data in the first place so it will not upset the fueling and put the light on..
 

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had engine light on for over 3 years now.At first I hated that light.now i have come to the conclusion that its going to stay with me. Hve changed fuel filter air filter sparks checked and rechecked for air leaks changed maf the car run better for about 6 months now I am cleaning the idle control valve. it could also be the throttle body,crankcase valve o2 sensors. if i were u wait till u have a problem then hope for the light to dissapear.
 
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