309 engine compression test

FrenchLeave · Post by **FrenchLeave** » 09 Jul 2005, 20:43

My wife's '90 309 fitted with the 1.6 XU51C carb engine has failed its MOT through emmissions. When warm it gives out lots of whitish brown smoke from the exhaust, although it seems to run fine.
It's the auto gearbox model and has never been very economical, giving about 26 mpg.
I've just warmed it up and carried out a compression test using a Gunson Hi-Gauge. Readings varied between 162 and 168 psi, putting a drop of oil into each plughole increased the lowest figure to 185 psi.
Two questions please:
1. What is the correct compression pressure? (are these figures OK?}
2. Anybody got any ideas?
It would be a pity to scrap it, other than this problem it's in pretty good condition and has only done 68,000 miles.

Cheers everybody,
Derek.

Peter D · Post by **Peter D** » 10 Jul 2005, 14:37

Failed emmissions on what all three figures or waht, This engine could be overfueling or burning oil thus the whiteish smote but that would give you a high HC figure. Detail the numbers. Regards Peter

FrenchLeave · Post by **FrenchLeave** » 11 Jul 2005, 22:29

Peter, thanks for your answer. Afraid I don't have any figures, the fail chit just said "CO excessively high, excessive smoke".