Occasional non-starting, my newer Sport

[rogerthechorister]

When I bought my newer Sport - N-plate - (with a plipper that does not work) the seller disclosed that occasionally she would not start. Normally it's first turn. He said simply to try again then again, and he'd never needed more than 3 goes. This has been the pattern for several months - but adverse developments are afoot.

Just in the last week she has outright refused to start twice - once on a petrol pump with a man with a large BMW offroader close behind who looked as if he was about to have a heart attack. I had to laugh. Anyway, that time I stopped trying, got out, locked the door, unlocked it again - and she went first time. So I suspected the immobiliser.

Then as I was about to leave girlfriend's again she refused (car, not girlfriend). This time the locking and unlocking made no difference. So I called her a fornicating lady dog - and the second time she went!

The only other relevant symptom might be that several times she has fired, made two turns of the engine - and stopped. This does not appear to predict whether she will go first or second try after that, or not.

I don't think it can be fuel pump relay, as once going I have never had a problem, and there appears to be no temperature correlation - although I think I have water ingress to carpet again, will check once warmer!

She has new crank position sensor, engine temperature sender. Goes like a rat up a drainpipe - maybe slightly better when not full hot. Temperature gauge is stable just above middle of gauge. Occasional tiny hesitation when flooring it at low revs. Turboplus appears to do exactly as it should (although I have not yet found the duration after which it backs off the boost).

Open to suggestions...

[Steve940estate]

Try the suppression relay first as it's easy.

[TheLeeds]

Originally Posted by rogerthechorister

I don't think it can be fuel pump relay, as once going I have never had a problem,.........

That's what I thought on mine, even more so after I tried another relay and it made no difference. Until one day I brought the original relay indoors and had a look inside it. There were two dry solder joints. Since I've resoldered it and put it back in the car, it's started first time every time. The hardest part of the job was getting to the relay, but if you pull out the liner from the tray under the stereo you can get straight to it.

[rogerthechorister]

Started like a bird this morning, first turn.

[Steve940estate]

Mine didn't start once then it was OK for a few weeks, it did it again and then next time it wouldn't go at all. It made finding the problem easy as I just swapped things over until it went.
I now carry the two relays, a crank sensor and an ignition amplifier with me just in case.
I resolderd my relays but a genuine Volvo suppression relay I had was OK and the internals looked slightly better made than the others so I have that one in the car now.

[Rversteeg]

I have had intermittent problems with my immobilizer of my 940 LPT. It would typically fire, run for one or two seconds and then die. After each restart the run time was shorter to not firing at all after two or three attempts. During this time the "check engine" light would stay on, so after a while I could predict a start failure. If the light did not go out immediatly, the engine would stop after a few seconds. I tried swapping the antenna ring around the ignition key, no effect. I also tried swapping the immo-module. I used the old antenna ring and taped it to the key that belonged to the replacement immo module, worked fine but did not cure the occassional starting problems. Finally I replaced the ECU and haven't had a starting problem since.

[rogerthechorister]

Thanks. It so happens I have a spare ECU!

[TonyS9]

According to google, N-plate is 1995 so If this is Volvo guard 1 it will not turn the starter if its immobilised. If you somehow have guard 2 with the fat key there maybe problems with the key reader and you could bypass the module.

If you have fuel power/pump issues I think it would show up during running.

[Steve940estate]

Glad I could help.

[rogerthechorister]

Volvoguard2 is what I got! And the plipper does not work. It hasn't (according to the former owner) for ages. He said he just never replaced the batteries when it stopped working but I have replaced the batteries and zilch. I have three cars like that! And a fourth much older with an aftermarket system (Scorpion). When I can find someone competent to do it they are on the list for fixing.