Emissions Quesry - 2.0 Gti 8v MkIII

[Grovit]

Took the Golf for its MOT on Saturday.

Apparantly the emmissions are a little high on it   .

There are 3 emmisions readings taken - Lamda, hydrocarbons, and something else. The guy at the workshop said he didn't think it was the cat as the Lamda one was ok, he suspected that a sensor had gone therefore throwing the emmisions out. This may help explain why she runs a little lumpy on tick-over.

So basically, I need to get the car checked over by an emmisions / diagnostic specialist - any ideas.  I could take it to a VW dealer, but I'm a bit reluctant to do that as I know the prices will be horrific.

Any help would be appreciated  


(BY the way - car recently serviced and new spark plugs have been fitted - also will be checking leads for any breaks this w/end.  Also no engine, airbox or exhaust mods)

[mk1]

What were the gas readings for the lamda, hc's and co.
Steve.

[Grovit]

er, I didn't get them :-[.  All I know is that the Lamda ones weren't too high - sorry that's probably not much use.

[golfvr6]

How do they calculate the lamda value?
I thought it is calculated off the other values?
May be worth getting the lambda probe tested anyway.

[mk1]

The MOT garage should have given you a copy of the emission results, if it failed on high HC's or CO% it may be a fault with the o2 sensor in the exhaust. Under the bonnet find the wires that go to the sensor in the exhaust, disconect the plug to the signal wire (usualy a single wire, poss black, next to a 3 wire plug) and heat up the engine, put a volt meter on the exhaust side of the wire and you should get a voltage reading bouncing 'tween .1 and .9volt.
Steve.

[Grovit]

Cheers

Didn't receive a readout from the MOT station I'm afraid.  Will take a look at the oxygen sensor and do a check on it.  Changed one a while back on an Astra I had - not to big a job, so will maybe look at doing that then.