1989 Volvo GL - Very hard to start when cold, rough idle.

zemudkram · Post by **zemudkram** » 07 May 2009, 04:32

Hi all,

I have an 89 240GL wagon that has a problem starting first thing in the morning. It will start after about 5-10 minutes of trying, with the odd half-start and backfire.

Once started, it idles very roughly and will almost stall if I push the accelerator too hard. If I can get it past 1500-2000 rpm it will suddenly pick up and run sweetly.

It carries on like this for about 10 minutes then it's fine.

For the rest of the day, even if I've left it for 8 hours or so, it will start just fine, though I noticed on the way home from work today that it idled a bit slow, and was just a little hesitant for about 5 minutes.

It's a B200E non-electronic injected engine.

The fuel pump will whine a bit when it's below a quarter tank, which may be related, but also may be another thing on top of it.

From what I've read, I'm leaning towards a relay issue, but would like to hear what you all think about it.

Cheers

Post by **vegasjetskier** » 07 May 2009, 13:14

Apparently your engine has a cold-start valve. Maybe that's the problem.

It's part #16 in this diagram:

240FuelSystem1989-1.pdf: (144.6 KiB) Downloaded 600 times

It looks like it's fed by pipe #19 in this diagram:

240FuelInjection1989-1.pdf: (163.87 KiB) Downloaded 451 times

Post by **billofdurham** » 07 May 2009, 16:08

zemudkram, welcome to Matthew's Volvo Site.

There are several possibilities for poor starting on this particular system.

vegasjetskier has pointed you in the direction of the cold start valve (injector) which is quite easy to check.

With the engine cold, clean around the the cold start injector to stop any dirt getting into the system. Disconnect the electric plug and the fuel pipe, remove two screws and the injector with its seal. When refitting you will need a new seal which is, in fact, an O ring.
Reconnect the pipe and the electrics.
Hold the injector over a glass container, switch on the ignition and run the starter motor.
The cold start injector should spray for 12 seconds at an engine temperature of -20C. Higher temps decrease the injection time and it ceases completely above +35C.
If no fuel appears, remove the plug and check, with the starter motor turning, for 12 volts across the socket pins. If you have 12 volts the injector is faulty and has to be renewed. If you don't have 12 volts the wiring or the thermal time switch is faulty.

If you need to test the thermal time switch the engine temp must be above +35C.
Remove the cold start injector and hold it over the glass container. Operate the starter motor.
The cold start shouldn't spray as the engine is hot. If it does spray the thermal time switch is faulty and should be renewed.

Other things to check are:
Leak in the intake system.
Airflow sensor plate out of adjustment.
Fuel distributor or airflow sensor sticking.
Line pressure too low.
Control pressure incorrect.
Rest pressure incorerect.
Injectors leaking.

Bill.

zemudkram · Post by **zemudkram** » 08 May 2009, 04:26

Thanks for that - those diagrams are handy

I'll try to get to that this weekend (thankfully the neighbours are away so I won't be annoying them with car noise...), and report my results.

Cheers

zemudkram · Post by **zemudkram** » 08 May 2009, 20:19

Ok, this is a little odd...it started first thing this morning. The only thing that's changed is that I've put some petrol in it. So I may have sent you all on a wild goose chase!

I'll do the tests, and at the same time I might see if an idle adjustment is necessary, since it idles at about 500rpm when cold (too slow?).

Thanks for your help though

Mark