I had been on the hwy for a few minutes and had to give gas to maintain speed of about 100-110kmph (X 0.6 to get mph) up a slight long incline. Car started bucking. Eased up on gas, bucking/jerking stopped but couldn't keep up with traffic. Dropped into 4th from OD and tried accelerating, still bucked. Eased up and exited hwy. Was it back-firing?

Drove until found side street. Car behaved fine. Knew I was near oil refill level so put in a liter. Level then read close to full. Had to get back on hwy but didn't need to accerate to 100. Car behaved fine at 80-90. Got off hwy and have driven for a few hours since with no probs doing up to 80.

Any clues as to what the problem was/is would be appreciated I don't want to be tearing everything apart.

I don't think it is timing, as no rattling (due to pre-ignition) and car was okay on uphill town driving. I don't think it just needed oil (oil light didn't come on). Don't think it was the trans. (M46)

Bad fuel? Carbon build-up? Fuel delivery problem? Ignition coil? Condensor?


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1980 245 Canadian B21A with SU carb and M46 trans