Car starts fine in shop at 15C. Put car outside in -20C overnite.
Next morning at -20C , car turns over fine , coughs like it is going to catch then doesn't. Swapped out fuel pump relay with new one, no difference - I could hear the main pump start up and keep running while cranking over.
Replaced plugs, wires, rotor, cap (cap had 3 of the four pins eroded away to almost nothing I don't know how it ran so smooth with the cap like that - also there is oil around the inside rim of old the cap), swapped coil. Squirted some "quick start" into throttle body. Still no start in cold but will start if I bring it into shop and let it warm up. Noticed 3 or 4 very tiny cracks in the intake bellows.


Did get it to start once outside in cold but only after considerable cranking and applying heater to area around exhaust side aimed at distributor and shaking banging the hell out of the fuse/relay board while cranking - go figure.
This after all maintenance mentioned above was performed. It purrs like a kitten when it does get started even in the cold weather.

I checked the wiring harness and it is in suprisingly good shape, no frayed or loose ends.

I am wondering if it is the Hall Sensor...

I am a big fan of the FAQ for 700 series on this site, simply amazing , and have read plenty.

I am know officially pulling my hair out.
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1985 740 GLE, 1981 245 Ice racers

I seem to have gotten rid of (I am hesitant to say "solved" as I am not quite sure what the exact problem was) the cold start issue. Car has now started (almost instantly with no cranking at all!) half a dozen times at -20C and colder.

What I did to car...

1) put lots of methyl hydrate in gas tank
2) replaced fuel filter (although old one seemed fine - could blow through it)
3) tightened intake manifold bolts 1/2 to 3/4 turns each (i had removed manifold and installed new gasket but never retorqued nuts after running engine)
4) end cap on elbow joint of vacuum hose connection at brake servo broke offbn as i was driving into the driveway as result I almost put car through garage door as no power brakes. Diagnosed this and repaired by hot gluing beer cap over top of elbow - works excellent! I suspect that this was leaking vacuum before and had probably contributed to vacuum leak related cold start issues.
5) cleaned intake bellows and applied silicone to the small cracks in it.

Thanks for pointing me in direction of vacuum leaks
Angus
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1985 740 GLE, 1981 245 Ice racers

Before you pull your hair out try replacing the module on the left side by the headlamp. That little black thing amplifies the signal to the coil to make a spark in conjunction with the ECM. Living in Maine I used to keep a good used one in the glovy just for incase. The hall switch can be bad also. Take the dist. out with it still conn. and turn ignition on. Spin the dist. over and check for spark. If there is no spark do the scratch test from the conn. that will produce a spark, if no spark then it is the module. Hope that helps.

My 86 B230F (248K) would not start very well either. (below about 15F) It would fire as I was cranking it but would just not keep running. If I kept cranking, it would eventually keep running as long as I kept the starter going for some time. (luckily the starter didn't fail)
Anyway I finally started to look into the problem last summer. I suspected the ECT. I broke open the harness up on the passenger side tower and ohmed it out. It read open. I went down to the sensor and ohmed it out and it was ok.
So I reconnected it and tried it again up above and it was ok also. WTF? (bad connection I guess)Well after that I could tell it was running too rich. I could smell it in the exhaust and my fuel mileage dropped. It also idled rough. I tried to lean it out by cranking the air mass meter but it ran out of adjustment. The idle did smooth out though.
And it now starts OK when it's really cold out.
Obviously there still is a problem with something (AMM, I think) but when the ECT circuit was open I think it was running in a default mode. Started and ran great when warm and got good mileage (about 26MPG) But when the ambient temp was below 15F, it was just hard to start. Ran OK after it started.
The engine harness is a piece of crap though. Lot's of bare wire here and there. I just put a new end on at the starter solenoid. (no crank condition)
Maybe next year I'll get the ambition to work on it again. Or if it leaves me sitting along side the road. LOL
Just sharing my experience with a similar sounding problem.
John

My response to your post isnt very technical-but-had the same problems as youve indicated the other day, was down near 0 degrees F here in NJ. I added a bottle of fuel de-icer to my 86 244 that had been recently purchased--the car had been sitting for a few months with a near empty fuel tank by the previuos owner. After adding the fuel de-icer and keeping the tank above half full the past few days--car has started right up--. Good luck to you and all our volvo freinds to the north

I also removed the intake manifold 2 months ago to inspect wiring harness and test ECT cleaned out flame trap. Everything was fine. Replaced manifold with new gasket. I cleaned both mating surfaces and installed new gasket. Should I have used any gasket goop or silicone along with the gasket or not? I didn't and I was wondering if this may allow for a vacuum leak when really cold? Also I can rotate the fuel injectors rather easily , wondering if the "O" rings should be replaced and how to do that.
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1985 740 GLE, 1981 245 Ice racers

Do not use any type of sealant on that gasket. If you have torqued the manifold properly the gasket will seal just fine.