Galaxy Mot Emmision Failure

[Guest yzfr1boy]

hi every body well my bus failed its mot today on emmisions

 

co 2.56% fail

hc 140 pass

lambda 9.30

so tried plugs air n fuel filter as not been done for a while

had a new maf meter last month as the power dropped

it seems to be using lots more fuel

so does any 1 have any ideas as im thinking lambda sensor next but a bit hesitant as i tried 1 a while ago when i had the poor performance fault and it did not alter the emmisions when checked,any ideas fellow bus drivers! n reg 2ltr 8v

Edited January 26, 2007 by yzfr1boy

[Guest mcyoungy]

temperature sensor? thinks it's cold all the time so puts the "choke" on?

 

maf meter again? wrong one? reading too much air flow so adding too much fuel?

Edited January 26, 2007 by mcyoungy

[Guest Cepheus]

Whether you want to risk it at a Fraud dealers or not, but most will do an "emissions service" for about

[Guest yzfr1boy]

yer it was a genuine maf meter from dealers with the same part number gonna try n get it to auto electrics this week i think

[seatkid]

surely you meant lambda = 0.93

[Guest yzfr1boy]

yes sorry it was 0.93 lambda reading

[redneck01246]

did you give car a chance to warm up before you took it for mot

which is always a good idea (speaking from past experience) bro inlaws 2.8 failed and mates 2.0 failed initial test but after i ran them for ten miles up and down the local bypass both passed well within limits (test centre is only about 3 miles away)

may not work but it is free to try :)

[Guest yzfr1boy]

yer tried a new lambda sensor today and tried a new thermostat still the same it ran 8 mile to work b4 i cat tested it again and the readings didnt change ordered 2 new cooling sensors for it as im running outta ideas now

 

2 lambda sensors

thermostat

maf meter

forte fuel system cleaner

cleaned egr valve n throttle housing n idle control valve

cleaned sensor connections

plugs air filter n fuel filter

oil n filter changed every 6k

still lambda 0.93

co 2.56%

hc 140

[littledaz]

I take it your catalytic convertor is OK? With your engine cold, try tapping the casing to see if the "brick" inside is loose. The only thing that would substantiate the sensor side of things, is the fact that you said it seems to be using more fuel. Your HC reading of 140 indicates little unburnt fuel. The cat won't affect the fuel consumption but, will make your emissions high at the exhaust pipe if faulty. Does it run OK otherwise and how many miles has it covered?

[Guest Cepheus]

Slighty less techincal than the things you have tried to combat the emissions problems, but have you tested the emissions with super unleaded in the tank?

[Guest yzfr1boy]

no never tried super unleaded in it,its lucky to be getting a hundred mile outta 20 quid fuel,it used to about 140to 150 mile

its done 170 k had new cam chain recently and i checked the compresions and they were ok the car drives fine

[Guest yzfr1boy]

tried a new ecu cooling sensor today and the gauge sensor but still no better on the emission side

checked the resistance of fuel injectors" 14 ohms "then removed rail and checked spray pattern after local mechanic who uses omni scan diagnostic equipment suggested it the pattern on all 4 are the same not conical just a straight jet gonna try the fuel pressur side as he says if the car is putting 2 much fuel in the lambda will weaken off to try n compensate for the over rich fuelling IS THIS RIGHT? any thing else to look 4 please as im starting to think i shouldnt of wasted cash on the dam thing

[Guest mcyoungy]

try getting your injectors ultrasonically cleaned.

[Guest yzfr1boy]

checked the fuel pressure today thats ok cat looks ok 2

forte fuel rep gave me a bottle of specialist injecter cleaner so will keep you posted incase it works but any more ideas more than welcome folks