Starting problems

[chippie]

I'm having some problems with starting my 440. It's the 1.8Si with the B18U engine.

Most of the time it starts just fine.

Sometimes it will start, then the revs will plummet straight away and will stop if I don't push the acellerator a few times until it sorts itself out.

Thenk sometomes it just won't start. Turn the key and it turns over, but will not actually start. It may take three attempts to start, or thirty. Then it will randomly start and run fine.

For instance today, took one trip, then when I got in it wouldn't start on the first three attempts (turned over but nothing else) then started fine. Then went to Tesco, and afterwards it would not start. Even got as far as calling the breakdown people to tow me home, but then after 25 minutes it started fine.

I'm really confused by this intermittent fault, and not sure quite what to look for, as it doesn't happen all the time.

I know it's not the battery or alternator, because I have replaced them recently.

Sometimes there is a whirring/clicking noise after starting (and sometimes after it doesn't start as well). Could this give some indication of what it might be?

[Paul240480]

I'm hazzarding a real wild guess here, but could your starter motor be on its way out? When mine began to go on my 480, starting was very erratic.

[chippie]

Could be I suppose, but it's really random, and starts more times than not.

Is there any way to test a starter motor?

[Paul240480]

Can only suggest to wait till you've got the non start 'syndrome' then put in gear and rock the car forward & then backwards a few times so it turns the engine a smidge. Then try to start. This can free up the starter temporarily.

It worked on mine everytime till I had the motor changed & mines auto. Just knocked it into 'D' then rocked it fore & aft and off it went. Right 'ball_ache' tho'Lol

[chippie]

I tried that yesterday, and it didn't appear to have any effect. Still took another 10 minutes till it decided it would start.

[bkf_uk]

Sounds to me like your fuel pump isnt arming up, check the rely. if that isnt the problem do the usual checks :- is there a spark yes/no, dist cap, rotor arm, coil ect

regards
Bryan

[chippie]

Sounds to me like your fuel pump isnt arming up, check the rely. if that isnt the problem do the usual checks :- is there a spark yes/no, dist cap, rotor arm, coil ect

regards
Bryan

Is the relay in that triangular shaped section up near the windscreen? If so, which one is it. My haynes manual doesn't have a lot to say about relays and their location. And how do you test a relay?

Thanks for your help!

[Baffler]

The Bosch starter motor in the 400 suffered from a problem with the armitige. A piece of the armitage, where the brushes run on, melts away and forms a gap between the brush and the armitage, hence nothing happening when you turn the key. I believe Volvo introduced a second starter motor which they sourced from Japan. Another sign of failure is a very slow and sluggish turn over.

But you're not suffering from these symptoms...are you?

As said before, possibly fuel pump or faulty fuel relay. I don't think anyone knows which relay is which in the 400 but the fuel relay should be one of the larger ones.

Hope you get sorted

[chippie]

The Bosch starter motor in the 400 suffered from a problem with the armitige. A piece of the armitage, where the brushes run on, melts away and forms a gap between the brush and the armitage, hence nothing happening when you turn the key. I believe Volvo introduced a second starter motor which they sourced from Japan. Another sign of failure is a very slow and sluggish turn over.

But you're not suffering from these symptoms...are you?

As said before, possibly fuel pump or faulty fuel relay. I don't think anyone knows which relay is which in the 400 but the fuel relay should be one of the larger ones.

Hope you get sorted

No, not suffering from those problems. Only possible thing that may indicate a dodgystarter is a strange whirring/grinding noise that sometimes happens when the enging starts and the starter motor stops.

I think i'll investigate the relays to start with!

[Martin Cox]

It might be worth checking the flywheel position sensor. They can go intermittently open-circuit before they fail completely. I had this happen when I had a 340 with the B172 engine (essentially the same ignition system as the B18U) and the symptoms were very similar to yours. Replacing the sensor cured it completely. I don't think they're too expensive

It might be worth removing it and cleaning it and checking the wiring. The DC resistance of the sensor should be 220 ohms (+/- 60 ohms) according to the Haynes manual.

Hope this helps

Martin

[Paul240480]

It might be worth checking the flywheel position sensor. They can go intermittently open-circuit before they fail completely. I had this happen when I had a 340 with the B172 engine (essentially the same ignition system as the B18U) and the symptoms were very similar to yours. Replacing the sensor cured it completely. I don't think they're too expensive

It might be worth removing it and cleaning it and checking the wiring. The DC resistance of the sensor should be 220 ohms (+/- 60 ohms) according to the Haynes manual.

Hope this helps

Martin

Yes, the flywheel sensor can cause all sorts of strange symptoms. (Mines a B18FT). Resistance Martin quotes is spot on. They cannot be adjusted, so if reading is correct, clean it. If resistance is 'out' change it. Got mine from a scrappy, having checked resistance fo £10.
Good Luck.

[Chris Wickers]

I too had similar problems - changed flywheel sensor - perfect ever since!

Chris

[chippie]

I'll dig out the multimeter and go test the flywheel sensor when it stops raining!!

I've done some googling, and it seems that sometimes these can have an intermittent failing when they are hot, which thinking back seems to fit with when the car won't start.

Normally shortly after a bit of a drive on a hot day..... Then a bit of a wait for it to cool down and work again. Could be onto something here!!

[chippie]

It would appear that the resistance of my flwheel sensor is around 160 ohms. Althougt within the 60 ohms of 220 should I replace it?

[Paul240480]

Try cleaning it, if that improves things, then BINGO cheapie fix. If not then replace. Not a lot to lose by trying a clean methinks.
Cheers.

[Rainbird]

Your problem sounds a bit like a problem I had on the wife's Saab 9000 which turned out to be a minute split in one of the vacuum hoses. It's worth a look even to find out that they're OK