Hi Bob.

First off, I presume when Chapman Cobble Hill did the head (this would likely be Greg there) that it was running fine when they were done. These guys know old Volvos as well as anyone and would surely have told you what was likely misbehaving in the shop. This a B230FD, right, not a B230FT? The difference between a '95 B230FD head and an earlier B230F head should be minimal. Reportedly the air intake porting is slightly different, in what way I'm not sure. The later B230FDs have Pulsair, which doesn't affect the head other than the mounting bolt holes. I sure wouldn't fault the mechanic in a small town like Ladysmith for not knowing old Volvos -you were lucky to find a mechanic having time to deal with you.

By noises on the way home back up the Island Hwy, can you elaborate? Steady? Occasional? Speed or rpm related? From the engine for sure? The drive train? Elsewhere? Growling? Vibrating? Whining? Progressively worse with time or engine temp?

If it will start and catch, but not idle and immediately wants to stall out then a number of possibilities. Is it like the ignition is starting to miss? Is there a sense of fuel starvation running out of steam? Or the idle simply dropping so low it just starts stumbling?

Thinking of basics, if the ECU doesn't know it's supposed to be maintaining idle or is unable to maintain idle then the idle may drop and the engine simply run rough and stall out as soon as you let off on the throttle. Will it stay running half-okay while holding the throttle open a bit? That would be confirmation of that possibility. In that case, the first thing I'd want to do is verify TPS adjustment/operation, starting with the click as you open the throttle. Next would be to verify the connectors are firmly seated on the TPS, IAC and AMM. Then verifying (using OBD Diagnostic Test Mode 2 as in the FAQ) that the injectors are each being pulsed (by feel) and that the IAC is operating (the tic-toc test, as I call it). A bad CPS is generally a cut-out/no-start issue, but in theory could be sudden rough running. Certainly worth a cable inspection and making sure the connector is solidly clipped

Defintely pull all the plugs and note if any are fouled differently.

As additonal food for thought, the last time I had a sudden mystery rough running leading to a no-start, and this was my '95 B230FD, it turned out to be a badly worn distributor cap/rotor. It's hard to tell by looking, you have to diagnose it by tracking it down to ignition being provided by the coil and not getting to the plugs. It was actually Greg at Chapman who found that one as my wife was stranded with the car not far from them and had it towed there.

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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now