Help - 98 Volvo S40 not starting

zapata

Hi,
1998 Volvo S40 2.0 125,000 miles petrol will not start.
Engine turning over but it will not fire up.
It was intermittent and would fire if left sit for a bit but now it won't catch at all.
I can hear the fuel pump priming and there is plenty of petrol in tank.
Tried a 2nd key in case it might be immobiliser.
Timing belt and water pump replaced 10k ago.
Any known issues that could cause this.
Thanks in advance.

Edit: can a mod move this to DIY repair section. Sorry

zapata

Ok a quick update.
The car started very quickly when towed and drove for about an hour and for 20 miles with no warning lights on the dash.
Car drove reasonably well but the clutch might be slipping.
Parked it up and now will not start off the key again.
New battery fully charged.
Plugs are newish and clean.
It has oil. Timing belt is good. Went though NCT 2 months ago and emissions were fine.
There seems to be pressure on the fuel rail - I removed the little cap and petrol squirted out.
Crankshaft sensor removed and cleaned.
My torque app with the elm327 obd2 Bluetooth won't read anything off it as this Volvo model seems to be older than obd2.

jimgoose

Hmm. Is the battery holding the charge? It could be a parasitic current drain.

zapata

jimgoose wrote: »

Hmm. Is the battery holding the charge? It could be a parasitic current drain.

The battery is new and a big amp one (62 possibly). I charged it anyway over night and tried it this morning. Engine turns over but will not fire up.

CianRyan

Disconnect the battery over night, connect in the morning and see if it will start?
Are there any after market electronics installed?

zapata

CianRyan wrote: »

Disconnect the battery over night, connect in the morning and see if it will start?
Are there any after market electronics installed?

Had the battery out charging last night and tried this morning.
There is a Sikura alarm there but is switched off - I don't have remote fobs.

Strange thing is it ran perfect when it was towed a few yards.

pitachu

I had a '96 2.0 s40 with the same issue, one morning when I had to call out a mechanic he suggested that I try replacing the coils (there is a pair of them under the plastic cover). I did this and never had the problem again.

Apparently the engine is the same as that in a Laguna and he had seen the same problem on them.

I don't know much about engines and this is me recalling a conversation from 7 or 8 years ago but it is something like casing cracks on the coild packs and moisture gets in.

Any how, maybe take a look at the coils - it was a DIY job and I changed the leads at the same time.

zapata

pitachu wrote: »

I had a '96 2.0 s40 with the same issue, one morning when I had to call out a mechanic he suggested that I try replacing the coils (there is a pair of them under the plastic cover). I did this and never had the problem again.

Apparently the engine is the same as that in a Laguna and he had seen the same problem on them.

I don't know much about engines and this is me recalling a conversation from 7 or 8 years ago but it is something like casing cracks on the coild packs and moisture gets in.

Any how, maybe take a look at the coils - it was a DIY job and I changed the leads at the same time.

I'll have a look at that.
I guess if there is a good spark - then coils should be good to start but it might run rough or misfire.

bear1

Could the crank sensor be kaput?
I know they usually need the engine to be warmed up before the the car stalls but if the sensor is in bad enough condition it could do that.
Failing that I'd imagine there is a spark issue. Injector pump?
When was the car last serviced?

zapata

bear1 wrote: »

Could the crank sensor be kaput?
I know they usually need the engine to be warmed up before the the car stalls but if the sensor is in bad enough condition it could do that.
Failing that I'd imagine there is a spark issue. Injector pump?
When was the car last serviced?

I thought about that cranky sensor and I might try one or two from a breaker. It was filthy before I cleaned it.
If there is pressure on the fuel rail - would injector pump still be affected?
Car got a service in summer but I did notice that the oil level was at the lower end of the dip stick mark. I have added some oil to bring level up.

toyotaavensis

maybe the starter motor since she started off a tow?

bear1

Dont get a crank sensor from the breakers, you dont know the condition and you could up back at square 1.
Get a new one, they aren't expensive.
Failing that, cheapest option is to get a diagnostics done.

zapata

Update.
The crank shaft sensor (aka flywheel sensor) was duff.
Disconnected the connector near the bulkhead to measure resistance - should have been about 200 to 300 ohms. My bad one was reading 10 times that at 2 Meg Ohms. I discovered by accident that if I the changed multimeter to diode check and then back to resistance, it would reset the sensor and the car would start once. Weird but effective. Picked up a used sensor on ebay and fitted it - will see how long it lasts. :rolleyes: