This is really doing my head in. I bought my R-reg Brava 1.9td in Feb 2006 and a couple of months later had to get the glow plugs replaced. Everything was fine until Septemeber when the glow plug warning light starting flashing again and over the coming months the first cold start of the day got increasingly more sluggish. I took the car to my local garage 2 weeks ago who've been mending my cars for 20 years and they checked it and found that the garage that fitted the glow plugs last year fitted cheap ones and 3 were knackered. The lads in the garage fitted a new set of best-quality glow plugs (which were actually cheaper than the other garage charged me for the crap ones last year) and everything seemed fine. Until an hour ago that is when the glow plug warning light started coming back on again and it's now coming on every time I start the engine.

Does anyone have any idea what the hell is causing this as I am REALLY getting fed up.

Now i asume your letting them heat up before firing up the engine (every time), am not trying to sound sarcy but needs to be ruled out, so we can help.

mountainmachine said:

Now i asume your letting them heat up before firing up the engine (every time), am not trying to sound sarcy but needs to be ruled out, so we can help.

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No worries. I presume you mean by that waiting for the glow plug light to go out after switching the ignition on then starting the engine when it's gone out. If so then yes I do - the warning light then comes straight back on after the engine starts.

That little light doesn't mean Glow Plugs are faulty necessarily. The glow plugs are only to start the car and they are never used again.

That warning light means preheat warning, also not sure but the JTD has a fuel heater to heat the diesel before the car starts. Etc. Could be that, but again check the glow plugs are at fault, afterall they will have a 12mth warranty.

With these temperatures lately things like preheats might be playing up, but depends how cold it is and if it happens when its not -4oC. Thats where my knowledge of oil burners ends... lol well for now anyway as my sister has the JTD.

as long as the engine is still starting ok i wouldnt worry about it.

JoskeJTD said:

That little light doesn't mean Glow Plugs are faulty necessarily. The glow plugs are only to start the car and they are never used again.

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Yeah - I've been told that by someone but apart from the glow plugs isn't there only the timing box (?) left that could be faulty? But the garage checked that and said it was OK. We've had really cold mornings and my car is parked in shadow so it's even colder where it's parked and that first start of the day the glow plug light takes ages to go out before I can start the engine.

It could be as simple as another busted plug. they do blow prematurely sometimes. there isnt much choice of plugs, the most common and easily available one are Bosch, Beru and champion. use these and you cant go too wrong.

the preheating depend on the engine, so which engine do you have exactly ??

on the TD100, there is post heating after starting (the glow plugs come on again to improve combustion when warming up), the length of which depends on engine temperature. this is controlled by the ECU, which in turn depends on the temperature sensor. Check how long the plugs are turned on for after starting (use a multimeter or small 12V bulb) on one of the plug terminals, it might be easier to wrap a short length of wire temporarily around one of them). start the engine and time the post heat period, it should be less than a minute i think. repeat when the engine has warmed up and compare the times. if the warm start heat is not much shorter, there is something wrong with the temp sensor or control unit, and this will blow plugs prematurely.

it would probably do no harm to get a diagnostic done and check that the ECU temperature reading is correct

Owen.

Hi Owen - thanks for the reply. I've got the ELX 100TD and I think the garage put in NKG(?) plugs. The first cold start of the day takes significantly longer than when the engine's warmed up - even with the new plugs. The warning light actually stopped coming on yesterday but now it's back. I don't know if this is of any help but after the new plugs were fitted I noticed this strange regular tapping noise coming from just behind the steering wheel area of the dashboard every time I switched the ignition on - this went on for a few days and had never happened before. Then on one final occasion when I switched the ignition on the tapping slowed down, changed to quite a loud knocking noise and then stopped and it hasn't done it since.

My garage has reaffirmed what someone else said on this thread that the cold weather we've had may be having an effect on this and as my car is parked out of the sun this won't help either - and they also mentioned that the glow plugs could be coming back on again after starting like you say. But if that's the reason then wouldn't the warning light only come back on after that first start of the day?