Puff of blue smoke on start of 1.6 hdi C4

[boristhespie]

My Other Half's 1.6hdi C4 has a puff of blue smoke on starting and only on starting.

I have been told by a ex mechanic that this is simply a small leak in valves(?) and it is nothing to worry about. In fact he says is libricates the valves(?).

The oil level doesn't seem to go down. So it kust be a tiny amount if oil even though the puff can be fairly thick (although not all the time).

Can anyone throw a light on this and is it dangerous. I ask because she needs her timing belt done and we don't want to throw £600 at a car (which also needs new pads and discs) if the engine is knackered.

Any advice would be appreciated.

[Doo]

My Other Half's 1.6hdi C4 has a puff of blue smoke on starting and only on starting.

I have been told by a ex mechanic that this is simply a small leak in valves(?) and it is nothing to worry about. In fact he says is libricates the valves(?).

The oil level doesn't seem to go down. So it kust be a tiny amount if oil even though the puff can be fairly thick (although not all the time).

Can anyone throw a light on this and is it dangerous. I ask because she needs her timing belt done and we don't want to throw £600 at a car (which also needs new pads and discs) if the engine is knackered.

Any advice would be appreciated.

Are you certain it's blue smoke and not grey? I would be inclined to think it's more likely the start of a leaking injector (dribbling from the nozzles on shut down & coming out as unburnt fuel upon start up).

It could be the valve stem seals, but you would notice smoke on the over run (slowing down by lifting off but not changing gears) as a puff when accelerating again.

It might even be an indication of the turbo wearing out. These don't have a bearing as such, but rather use pressurised oil as the bearing. When the turbo starts wearing, almost always caused by poor servicing in these engines, by that I mean changing oil far beyond the recommended limit, (I do mine at 6k to 9k) it will allow a little bit of oil through. When you start the engine, it gets blown out the exhaust. The Achillies heel on these is a small "filter" on the oil feed to the turbo in the banjo bolt. When the carbon starts building up, these little filters get choked to the extent that they start starving the turbo of oil. They start whistling and then it's just a waiting game.

[MattBLancs]

Out of the loop on garage prices, but £600 sounds expensive for belt replacement on a 1.6 HDi??

I wouldn't worry about a tiny "puff" on start up, smoking all the time yes, but just a touch on start up should not be major cause for alarm.

[Doo]

I didn't read the part about the belt, sorry.

If you were near me, I'd do it for the cost of the belt kit & water pump and time. I think they are about 2hrs or so (depending on whether we encounter rusty bolts....). But I think as Matt suggested, six hundred is a little on the high side.

Belt & water pump kit is around £80 give or take. If it were me, time would be £30ph and call it max 3hrs including discs & pads.

There are lads/lasses around who do homers, but you want someone who knows what he/she is doing because although it's not the most complicated belt swap, it is a faff and things can be damaged if not done right. Look for an independent Citroen/Peugeot specialist because although they might be expensive per hour, they usually have vast knowledge of the Marque and can do them in their sleep, thereby take less time.

[boristhespie]

Thanks for the advice. I will take a video of it. It is just start up.

[Gibbo2286]

Puff of smoke on start up possibly the valve guide seals hardened with time.
Timing belts are sometimes a fixed price deal a the Citroen dealer, worth looking up, I had my C5 2.0 Hdi done for £345 all in and all done in a morning while I had a wander round town and a burger in McDonalds.