Vectra diesel cold start problem

[...]

Yes.

The former.

It shouldn't be necessary with any vaguely modern diesel, but might possibly get you out of trouble temporarily when the next glowplug fails. Only danger is, glowplugs take a fair bit of current, so if the battery was already in a low state of charge, it *might* tip the balance towards

*not* starting!

Well, you could have diagnosed the faulty glow plug by measuring its resistance (with it disconnected), or checked that each glowplug was getting a feed (by using an assistant to operate the key.

Chris

Your symptoms are usually caused by faulty spill pipes from the injectors, a very cheap and easy component to renew.

[snip]

Temperature at 9am this morning 3 deg. Probably colder overnight, good layer of ice on windscreen.

Engine started first time. But ran really lumpily for at least 30 seconds despite trying to run it at a fast idle - 1200 to 1500 rpm.

I've never owned a diesel before - is this to be expected?

If not, it is reasonable to expect that the annual service should have found the fault?

As Mr C mentions, injector leak off pipes need changing. Easy cheap job.

What will also help is parking the car with the front facing downhill. That way the diesel does not drain back to the tank as easily and the car can start more readily. If the car still has problems starting after changing the leak off pipes, then it can get expensive. Dave

[...]

No.

It seems likely that two faults existed at the time you bought the car; a failed glow plug, and faulty spill pipes.

As the seller was helpful in fixing the glow plug, why not go back to him with the poor cold-running problem?

Chris

Seller is suggesting that initial lumpy running may be simply a characteristic of this model. I will see what it's like after the expected cold night on Wednesday.

I tool the plastic cover off the area around the injectors and looked at the spill pipes. They look clean; they are black - something like hard rubber - and along with the other writing on them there is what might be a date code - 02/09/09. Bearing in mind that the car was built in 2004 this might suggest that the spill pipes were replaced n the autumn of

2009.

There's no evidence of fuel coming out; I will look again with the engine running and in good daylight; if they are leaking would I expect to see any evidence of fuel?

the problem is not of fuel leakage but of air ingress, the air gets in the pump and either prevents it starting or makes it run rough till it is cleared. Step one, renew the spill pipes with genuine ones.

Lumpy running when cold is not a characteristic of this engine. Mr C is right, air leaks in, fuel rarely leaks out. Change the spill off pipes first. Also check that all the glowplugs are working. Sounds like another one may have failed. Dave

Have the injector leak off pipes in the head replaced. This will be the problem.

Tim.

Indeed. Some long needle nosed pliers needed and patience.

Tim.

I have the Isuzu 1.7 CDTI in a Combo. Dash read -2degC this morning.

Ignoring the glow plug light and going straight to cranking resulted in about 2 seconds of starter before she fired, there was a split second whilst all pots caught and some white smoke from the exhaust as you would expect which soon cleared, at which point it was running smoothly at 950rpm.

If I had waited for the g/p light to go out it would have fired sooner upon cranking without the white smoke but otherwise no change.

Both the 1.7 and 2.0 units can and DO suffer with tight valve clearances as the miles increase. Symptoms would be hard starting from cold, very rough running and alot of smoke- very similar to failed glow plugs, but the unaffected cylinders would fire immediately, and keep firing. 2-3 minutes and it would smooth out.

The OP has fuel run back issues to begin with, there may be another underlying issue too.

Tim..

If the pipes have ever been replaced then the needle nose pliers are not so important as the hoses are usually strong enough to pull completely off the connections, but I once spent ages with several different pliers and cutters getting small broken bits of original rubber pipe off, on one of these engines.

the problem of fuel run back would not occur at all if the spill pipes went straight back to the tank, unfortunately they go straight onto the suction side of the pump, a one way valve would probably improve matters, but a sound pipe system is the first thing.

I was told that the glow plugs on these engines are not actually used unless the temp is below minus 7.

An update for you.

Seller lent me a courtesy car and took the Vectra to his tame expert. This is not the same garage that serviced it for him just before he sold it to me. By co-incidence this expert is the guy who has serviced this car from new for the previous owner.

Tame expert has not been able to replicate the starting problem, but:

1) the weather has not been particularly cold;

2) he has only parked the vehicle on the level; not quite steeply nose-up as it is in my driveway.

3) When he starts the car to check it he only runs it for a few seconds to confirm it is OK, so it stays cold. By contrast I always use it for reasonable journeys (minimum 15 miles) so it is is properly warmed up every time. This may affect the way the spill pipes seal.

However, tame expert has identified engine oil in the fuel; he thinks that the injector seals are failing and will need to be replaced. He explains that if engine oil can get into the fuel, then so can air; and this is what causes the starting problem.

Given that the car was made in 2004 but has only done 55,000 miles is it reasonable to expect the injector seals to be failing?

An 8 year old diesel with only 55k on it sounds like a recipe for disaster. Have you tried parking it pointing the other way?

Oil in the fuel and being hard to start parked nose up? The expert is right, the injector seals need replacing. Thats the expensive bit I referred too. I was quoted around £500 to replace the seals. Apparently the camshaft is in the way and has to be lifted up. I didn't get the job done - just made sure that I never parked the car nose up. Dave

[snip]

OK a more general question. Why is there any connection between the engine oil system and the injectors, so that a seal is required to keep the lubrication oil and fuel oil separate?

Sorry, don't know the answer to that one in any detail. Dave

[snip]

Another update for you:

Seller is Ray; his tame expert is Glyn.

Early January: Glyn replaced the injector seals, and Ray paid him to do so. Now when temperatures are above 5 degrees C the car starts reliably even when parked nose-up on a slope.

Cold weather during period 10 January to 24 January, and specifically 17 January when it was minus 9.5 at 9am. Car difficult to start, the more so when colder. Would crank OK, firing on one cylinder, then 2, then 3, finally sustaining itself. Took anything from 5 seconds to 30 seconds continuous cranking.

24 January: Ray takes car to Glyn in anticipation of very cold morning 25 January. 28 January: Ray returns car to me, saying that Glyn had replaced another glow plug. Supplies printout from Glyn's Picoscope clearly showing 15 second cranking, but battery good at about 10v while cranking.

Period 29 January to 12 February. No very cold weather, but at temperatures less than 1 degree would take several seconds cranking to start. Today (13 February), minus 0.5 degrees but had been much colder overnight; took 15 seconds cranking to start.

So I go to Glyn, bypassing Ray. Glyn clearly embarrassed that his diagnosis to Ray had not been passed on to me. He admitted that the new glow plug was not necessary, but he had fitted it under instruction from Ray.

Glyn's actual diagnosis is that cranking speed is not fast enough, and that this is because starter motor needs replacement (estimated cost £200). Since performance of starter motor depends on the number of times it has been used it relates more to the age of the vehicle than its (comparatively low) mileage, so on the face of it this is reasonable.

So my question: is this actually reasonable? Ignition clearly depends on high compression ratio to get the temperature required, but I would not have thought this was affected by cranking speed. Certainly I have had petrol engines that would start reliably even when the cranking speed was very slow; why should a diesel be so very different?

Any comments?

What should the cranking speed be?

continuous cranking.

Sounds like nonsense to me but then I'm no expert. Sounds a lot more like a bunch of duff glow plugs. Modern direct injection diesels start pretty well without them but in cold weather they may be needed. It could be that the relay that controls them is duff but surely they've checked this out?

Tim