running rich/exhaust dripping

[cjdonny]

i had the E30 checked before i put it into the garage for winter and was told it was /wouild fail emission test

serviced it today and noticed a fair bit of vapour unburnt fuel?

out the back box dripping out is this due to running rich??

i have a set of recon injectors to fit before taking it back for the emissions test

but noticed the cover for the ajustment screwis missing!so can i just get the garage to turn this a bit to ajust and get the emissions down for the mot in May

[Brianmoooore]

The liquid dripping from the tail pipe will be water, which is produced in large quantities by burning hydrocarbon fuels.
We need a lot more info. before we can begin to decide what's wrong with your car, such as the HC and CO levels it's producing. O2 and CO2 results are useful as well to decide whether it's running rich or lean, and to start to decide what might be wrong.
The problem with the CO adjustment apparently having been tampered with already, is that having it adjusted may well improve the running of the car, and bring the car within MOT test limits, but this may be just counteracting a pre existing fault, so the car may never run as well as it should.
Note than an E30 in good working order should pass the MOT emissions tests with ease, coming close, if adjusted to do so, to passing a cat. type emissions test without a cat. being fitted.

[cjdonny]

Thanks Brian 318 is m42

readings were:

Fast idle test

CO: 0.353 FAIL/0.200% Limit
HC: 69 PPM PASS/200 ppm limit
Lamba: 1.124 FAIL/0.970-1.030 limit

[Brianmoooore]

Those are cat. test limits. What model is your car, what's the build date/date of first registration, and does it have the original engine?

[cjdonny]

as far as i know its the original engine

reg date 28/09/90

[Brianmoooore]

If it's 28/09/90, and this is a UK MOT test, then it has passed by a mile. Limits are 3.5% CO and 1200ppm HC.

Does the car have a cat?

[cjdonny]

Right no cat on car

So they have limits set up wrong.

[Brianmoooore]

Right no cat on car

So they have limits set up wrong.

Definitely! Figures aren't ideal, though. That engine is definitely running a little too lean. Just the sort of thing that may be sorted by your refurbed injectors, so get them fitted before your test, and see if the figures improve then.

[cjdonny]

Thanks for info
If still high and I get them to ajust
What sort of figures should I be looking at to be running at the correct levels

[Brianmoooore]

It's not high! CO is too low. I can't tell you what it should be, because you haven't said what engine you have, but 1.0% CO is likely to be about right.

[harry_p]

The ideal lambda figure is 1.0, which indicates an ideal air / fuel ratio. Above 1 is lean, below 1 is rich, and, as Brian says the co level should be higher too.

Change the injectors, check the inlet and breather system for cracks and leaks, make sure the exhaust is solid with no leaks and get it retested.

At least then you'll have a base to work from.

[cjdonny]

Cheers
I did edit my post last night to say m42