almost failed mot due to emmisions

[hammy44]

hi all my 88 2.1dj almost failed its mot on emmisions as per last year the mot guy has advised me to get something done for next year has anyone got any sugestions as to what i can do about it he says its too much fuel.this year i changed the oil and filter fuel filter and new plugs.the van runs/accelerates and sounds great mot mans words.a mechenic adjusted the fuel mix 2days ago and said that was the best he could get it.any advise from you wizards would be gratefully appriecated as i dont know where to go now.

[icosahedron]

A faulty Temp II sensor could be the culprit. Also check that the connections on this circuit between ECU and sensor are good. Any electrical resistance introduced by dirty connections will enrich the fuel mixture as the ECU will be getting the signal that the engine is not up to temperature.

[hammy44]

hi icosahedron the red light in the temp gauge stays on most of the time could this indicate the fault as the sensor regards

[kit]

Did you replace the air filter?

[icosahedron]

The red light in the temperature gauge indicates low coolant level. There are two sensors that monitor engine temperature, one for the temperature gauge and the other (Temp II) for the fuel injection system. There is also a sensor inside the AFM for the fi system for measuring the intake air temperature.

Another thing that you should check is that the fuel pressure is within limits. You will need a gauge in order to do it.

[AdrianC]

The really simple question is "Was it properly hot when he tested it?"

I don't know how many emissions failures I've come across that've been down to lazy testers.

[hammy44]

hi kit yes air filter replaced adrianc yes he even got out his infrared temp gun and it read 80deg

[California Dreamin]

And what exactly were the emmisions figures?
Is he using the correct comparrison data for an '88' pre-Cat van?
I know Ian would say...fools Gold! GAS IT! you certainly wouldn't have an issue then....

Martin

[hammy44]

thanks for the replies temp 11 ordered from brickwerks hope i dont have to repeat the question later

[hammy44]

And what exactly were the emmisions figures?
Is he using the correct comparrison data for an '88' pre-Cat van?
I know Ian would say...fools Gold! GAS IT! you certainly wouldn't have an issue then....

Martin

over here we are gov run mot centers so assume everything above board no details given as it passed just.thanks

[California Dreamin]

Are you not given an emissions certificate...or print out? without knowing what your engine is 'putting out' how do we even know the parameters that it is being judged by are correct.
I vaguely recolect a pre-cat vehicle before 1992 being allowed a max CO content of 3.5%.

Martin

[hammy44]

Are you not given an emissions certificate...or print out? without knowing what your engine is 'putting out' how do we even know the parameters that it is being judged by are correct.
I vaguely recolect a pre-cat vehicle before 1992 being allowed a max CO content of 3.5%.

Martin

hi no we are only given that info if it fails.and as for the max co2 when my 98 merc an import without a cat was up i enquired about the emission test and was told it was the max co2 that they worked on.but thats good to know about max of 3.5% if cant get it through next year can hit them with what is the max you allow.thanks

[AdrianC]

my 98 merc an import without a cat

Blimey - where did that come from, to not have a cat so late? I thought the UK was amongst the last, needing 'em from '92.

Or has it had the cat removed...?

[hammy44]

hi adrianc,south african import imported into uk 2000 non cat stamp in engine bay.needed a front pipe couldnt get an after market one and one from mercedes was £350 and a cat was £600 bought an aftermarket cat one for £135.so it now has a cat.

[hammy44]

update, got sensor from brickwerks and fitted today.will get emmisions checked tomorrow to see if thats the prob fixed.been to mechanic today he said there should have been no problem as he had it at 1.5%