MK5 Golf - 1.9 tdi sounds really rough start from cold

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Tue 10 May 2016 22:53
MK5 Golf - 1.9 tdi sounds really rough start from cold - Roy Brown

Have a MK5 golf 1.9 tdi up for sale. A person just came to view it, liked it and then asked for the key to start it up. It started up but it sounded really rough once revved after 30 secs or, almost like the timing was off or it was off a cylinder (never sounded like this before) It idled fine, so I let it sit for a few mins once the person had left.

I then went to rev it and it sounded normal again, I took it out for a spin and just drove like it normally did. The car has been sitting in my garage for a few days so I put it down to the battery being weak, but just got it plugged it and all of the glow plugs had indicated a fault.

Has anybody encountered this problem before? Could it be down to a weak battery/glow plugs or could it be another issue??

Any help appreciated

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Wed 11 May 2016 07:48
MK5 Golf - 1.9 tdi sounds really rough start from cold - elekie&a/c doctor

Could be several things,but the battery will not cause this.These engines usually run fine even if the glow plugs are faulty . When was the last time it had an oil change?

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Wed 11 May 2016 11:52
MK5 Golf - 1.9 tdi sounds really rough start from cold - Roy Brown

Had an oil change 5k/6k ago

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Wed 11 May 2016 14:42
MK5 Golf - 1.9 tdi sounds really rough start from cold - chris.o

I have a mk4 Golf TDI with i'm pretty sure the same PD 1.9 engine in. I recently had the cylinder head off because of a headgasket issue. (different issue to you) but whilst removing the cylinder head i noticed it was fitted with hydraulic tappits (these are the connection between the camshaft and the valve.) After putting it all back together and starting it for the first time the engine was temporarily very noisy whilst the hydraulic tappits filled up with oil. You say the car has been stood for a bit. Its possible the tappits took some time to fill with oil after being stood?

Chris

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Wed 11 May 2016 19:49
MK5 Golf - 1.9 tdi sounds really rough start from cold - Roy Brown

Cheers for the replies so far. Could quite possibly be that Chris also, or is it possible that they re sticking?

I got the fault code cleared from the car, just to ensure that it hasnt been on the car for a while. But it returned after running, so have removed the glow plugs and the tips of them have some carbon(?) build up. So have ordered a new set to be sure.

Also started the car today from cold after letting it sit about 18 hours, but it started up fine!

Edited by Roy Brown on 11/05/2016 at 19:51

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Wed 11 May 2016 20:01
MK5 Golf - 1.9 tdi sounds really rough start from cold - elekie&a/c doctor

The reason I asked about the oil is that it is very important that the correct spec is used.The Pd engine uses the camshaft to drive the injectors.Inadequate lubrication can cause the system to clatter and wear.The glow plugs always have a carbonised look due to the combustion process.

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Thu 12 May 2016 12:51
MK5 Golf - 1.9 tdi sounds really rough start from cold - Roy Brown

Cheers for that. The oil I had used was just the recommended on euro car parts, and it said that it was also recommended for PD engines. After spending some time on Youtube watching a range of videos. I stumbled across one where the guy said he had a lifter sticking which is very similiar to what mine sounded like. Once again, I started the car today and no noise from it so it must just be intermittent.

Would the likes of Wynns hydrualic valve treatment be OK to use for a while then get the oil replaced after? The car is correct mark on the dipstick, so would I need to drain some of it out if I was to add the recommended amount of treatment?

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Fri 13 May 2016 09:03
MK5 Golf - 1.9 tdi sounds really rough start from cold - chris.o

Oil and filter change would be a good idea. Give it a run first, then follow the Wynns instructions. Does the valve treatment stay in? or do you run it then drain out?

If you know the cars oil change history then I think its ok to use (ie its had one every 10-15k) If its missed any I would be careful. Adding a cleaning/flushing agent to the oil might just loosen any deposits in the engine and make problem worse.

Chris

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Fri 13 May 2016 21:21
MK5 Golf - 1.9 tdi sounds really rough start from cold - Roy Brown

Thanks for that. Changed the oil and filter today and added the Wynn treatment. I says that it lasts the life of the oil and is oil soluable, so hopefully that will cure it! Cheers

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