!800E Running Rich

[VolvoFan]

My 1972 1800E (B20E & K-Jet injection) seems to be running too rich. The plugs are black and inside the tail-pipe is sooty. Also the exhaust smells rich. Ignition has been checked: dwell angle and timing set up as handbook specifies. Air cleaner is not dirty.

I've driven the car on some good runs recently (40 - 50-mile jaunts) and it starts & runs well. with good acceleration & high speed cruising.

Should I alter the idle adjustment screw or could the mixture be rich at higher revs than at tickover? In which case is there any other adjustment to be made?

The engine has done about 85,000 miles to date.

Useful suggestions will be much appreciated.

[Ron Kwas]

VF;

Cold Star Injectors (CSI, NOT Miami!) like to become incontinent after time, weeping to some extent fuel into manifold which is unnecessary and wasteful, and will result in those symptoms, but also certainly result in a rich condition, and poor fuel mileage.

To check, remove CSI after warmup...plug manifold vacuum leak while checking that pintle (injector valve-pin) is completely sealed. Injector should be leaking NO fuel into manifold...otherwise check after shutting OFF motor (but fuel supply rail pressure is still up...or should be!). Catch possible fuel leakage from CSI in a container. If leakage is confirmed, add injector cleaner to tank, or soak pintle in it directly for and hour, retry.

CAUTION: OBSERVE SAFE OPEN FUEL HANDLING PRECAUTIONS!

Good Hunting!

[VolvoFan]

Thank you for advice. Do you think the CSI should be the first port of call in this problem?

[VolvoFan]

Will carb cleaner harm the injector instead of using injector cleaner?