Engine ticking over lumpy and white smoke

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Tracy&Andy
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Engine ticking over lumpy and white smoke

Post by Tracy&Andy »

Hi guys

We recently noticed a small fuel leak coming from the diesel pump (Passat engine 1.9Td, probably 1996/7) so took it off to get it fixed by an expert.

We put it back on, the same way it came off, but now the engine is jumping around when ticking over and white smoke is spewing out (which we understand is un-burned diesel).

We have checked the timing (with a new belt) three times, and bled injector cleaner through the fuel line, but to no avail.

We've asked mechanics, and they say it is the timing (checked) or the injectors are blocked (cleaned).

Has anyone else had the same problem, or knows what else it could be? The engine was running great before the pump came off. We are going to return the pump to the expert who fixed the leak to see if he can see what the problem is, but any other suggestions would be welcomed.

Thanks, in advance!

Tracy and Andy
Happiness is Wedge-Shaped!

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ELVIS
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Re: Engine ticking over lumpy and white smoke

Post by ELVIS »

Have you checked timing on VCDS? Time up cam as per an IDI then set via VCDS. Timing should be within two parameters on graph.

Tracy&Andy
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Posts: 15
Joined: 09 Sep 2013, 12:57
80-90 Mem No: 25588
Location: London

Re: Engine ticking over lumpy and white smoke

Post by Tracy&Andy »

Thanks Elvis but we haven't got a connection to plug in the VAG-COM. Not that hi-tec, I'm afraid!

We have had the pump checked over and it is working fine, so the expert said it could be the Banjo bolts (supply and return) are in the wrong place, the four fuel lines are connected in the wrong order or there is air in the system (maybe a leak somewhere).

So we are going to double check all of these, next.

Thanks,

Tracy and Andy
Happiness is Wedge-Shaped!

lefty67
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Re: Engine ticking over lumpy and white smoke

Post by lefty67 »

Not had white smoke but had the lumpy running at idle. Coming from the fuel pipes from the diesel fuel filter. Large air bubbles going into the pump. Try fitting a clear fuel line from the filter to the pump, will be able to see any air bubbles.
Probably not your problem but cheap way to rule it out.
1.9td AAZ

T25 - an adventure before dementia

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