244 misfiring
 

Hi everyone
New to this site and new to Volvos, just got my first a 82 244gl, 4sp manual b23 motor (I think?)
Pretty new to working on cars but have some basic knowledge
So... Since i got it two weeks ago, occasional lurching forward in 2nd gear, which has quite suddenly turned to maximum ylurching when the engine eyes hot. Had to limp it home in 1st and 2nd at high revs. The guy who I bought it off said he's very recently changed the plugs, so I haven't bothered to do that yet. The car was sitting idle for a 3 years although he said he started it once every week and took it round the block.
I took off the distributor cap and blew any dust out and blew on the end of the leads, ran sweet after that (which was yesterday) so I thought it wa just gunk in there, but it happened again today after driving about 15 mins. The heat guage was fine, so the engine doesn't appear to be overheating. Anyway- why now? Thinking I should probably change the spark plugs despite what the guy said.
What do you guys think?
Thanks in advance from new Volvo lover!

it would help to know what fuel injection system it has, as troubleshooting the older CIS aka K-Jet systems is quite different than on the newer LH (EIS) systems, and 82 is right around where I think they switched. K-Jet has a fuel distributor and the injectors have no wiring to them, while LH has a fuel rail and each injector has a wire connected to it

some possible causes:

• bad fuel thats been in the tank for years
• bad wiring to injection and/or ignition
• erratic fuel pressure regulator

in my limited experience with K-Jet (on VW and Mercedes, never had a K-Jet Volvo), most problems I've dealt with were at idle or very low throttle settings rather than higher throttle.

If its LH, a candidate for erratic behavior is the crank position sensor, but this more typically results in a total shutdown or no-start (often when hot, then it works again when cool).