Poorly GTi…what’s the diagnosis, Doc?

[NorthernMonkey]

As mentioned on my other thread, a collection has occurred today, namely that of a poorly mk5 GTi DSG from @CraigRK’s son and formerly of others in this parish.

This popped up for sale last week following it breaking down in central Sheffield. It caught my eye as my very first car nearly 40 years ago was a silver mk1 Golf GLS auto (rip PWX406W) and the thought of cruising the streets with my discman (or iphone16) plugged into the stereo appealed in a nostalgic manner.

Luckily, I bought myself a new truck a few weeks ago…unluckily, it needed a full rework of the lighting system before it could get a test on it so it’s been all hands on deck getting it fettled so as collection of aforementioned Golf could occur.

As I write this sat in McDs in Glossop with a coffee and a £2 chicken wrap, it has performed faultlessly. Just need to get back to Colne now so it can be parked up in the workshop ready for investigation on Saturday as I’ve got a day of proper work to do tomorrow in Aldridge.

Updates will follow but initial digging suggests a buggered high pressure fuel pump, along with potential contamination of the rest of the fuel system. Either way, it will live on as Claire has already expressed an interest in adopting it.

[NorthernMonkey]

And we’re back and tucked up in the workshop for the night.

Technical investigations and updates to follow after the weekend as we’re busy tomorrow.

 

[ruffgeezer]

Well bought, this tickled my trousers but sadly I am not a man with means to move broken chod easily. 

[NorthernMonkey]

Managed to have a shuffle around at work this afternoon and got this off the truck

I made a bit of a start on it by removing the plugs and rocker cover. Everything looked to be in good order so I tentatively turned the key fully expecting the exhaust cam to remain motionless but no…everything turned over nicely and in sync albeit a little slowly. I stuck the battery charger on and it was showing 9.8v so I’ve left that connected to see if it’ll recover.

Unfortunately by this time, Claire needed collecting from the theatre up the road where she’s been running the box office all afternoon and the dogs needed feeding so little else has been achieved today.

The only relevant fault codes logged in the ecu are low rail pressure related…luckily,@Dave_Q has got a spare fuel pump I can try which I’m hopefully going to get my hands on tomorrow so the next step on Monday will be to fit that and cross everything I possibly can! 🤞🤞

 

[Agila]

Be interesting to see this fixed and roughly how much it ends up costing in parts and how much labour time etc. 

 

[NorthernMonkey]

The bit you’ve all been waiting for, folks…what’s actually wrong with the thing?

@Dave_Q has just been over and dropped a HPFP off for me to try as my instincts were a fuel pressure issue.

Whilst he was here, we whipped off the old pump to see if anything was obvious.

For those of you who aren’t familiar with this design of engine, the pump is operated from an hydraulic ‘bucket’ lifter which in turn runs off an extra cam lobe at the end of the inlet cam…

 

That’s the bucket and the black surface is treated to run off the cam lobe

Here it is pictured next to the fuel pump plunger. Note the design of the push rod which is spring loaded and has a collet on the top which sits inside the bucket of the lifter.

The above photos are of the new pump and lifter that Dave brought with him.

Spot the difference between that and the ones that came off the car, below…

Yep. The bucket has worn completely through and has not only worn away on the cam lobe but then, the fuel pump plunger has also worn away on the lobe too, to the extent that the large spring retaining washer has disappeared into the depths of the engine!

You can just make out the remains of the cam lobe with a lovely groove in it made by the pump push rod.

 

[NorthernMonkey]

So, what’s the plan?

It definitely needs a new inlet camshaft and fuel pump along with a new lifter. It would also be foolish not to replace the chain and tensioner whilst it’s apart.

Then, it’s a case of taking the sump off and thoroughly inspecting and cleaning that along with the oil pump and pick up whilst looking for any other signs of damage from the various bits of metal that have been ground away.

Best case scenario, it goes back together with the above bits replaced and sounds ok.

Worst case, it knocks its bits off due to damage caused by oil contamination.

We have a fuel pump and follower, along with a new housing for the chain. For the cost of a replacement cam shaft and a bit of time, it’s got to be worth a try before condemning the complete engine.

Place your bets now!!! 🤨

[SiC]

Keep the fuel rail valve off the top of the old pump. Very frequently have their connector broken off by kack handed individuals and aren't easily obtained. 

[SiC]

Real shame this didn't get the cam follower looked at earlier in its life. It's a consumable part on these engines (shouldn't be but ends up being) and super easy + cheap to change. 

How many miles has the lump done?

[SiC]

I'm glad ex- @dan95x, etc parts have come in use and potentially saving a car. 

[NorthernMonkey]

14 minutes ago, SiC said:

Real shame this didn't get the cam follower looked at earlier in its life. It's a consumable part on these engines (shouldn't be but ends up being) and super easy + cheap to change. 

How many miles has the lump done?

Around 127k so not too high.

Hopefully, it’s escaped any serious damage as it was apparently running sweetly up until it cut out in traffic the other week due to lack of fuel pressure.

The sump and chain housing are coming off tomorrow to see what we can find.

[cobblers]

If anyone can fix a mid-00s sporty ish VAG that someone else had given up on, it's you!

Have you still got my mums A3?

 

[NorthernMonkey]

1 hour ago, cobblers said:

If anyone can fix a mid-00s sporty ish VAG that someone else had given up on, it's you!

Have you still got my mums A3?

 

No. Got it rebuilt and running ok but it was a constant battle of wits between me and the DPF for a period of months.

In the end, it tipped me over the edge and I succumbed to the constant badgering of the guy who runs the second hand tyre shop across the yard to buy it off me.

A week later, it was on marketplace with a bypass pipe and a dodgy remap for £2k more than I sold it to him for. That was about the time I re-evaluated the demand for older VAG stuff in the Blackburn area.

Hey ho…it was a learning curve! 

[cobblers]

It hadn't given an ounce of DPF related bother when we had it, despite my mum just pottering about in it. I remember warning her against it when she first bought it. No doubt it's blezzing around the place with a couple of markers on the police national computer nowadays 😅

[NorthernMonkey]

8 minutes ago, cobblers said:

It hadn't given an ounce of DPF related bother when we had it, despite my mum just pottering about in it. I remember warning her against it when she first bought it. No doubt it's blezzing around the place with a couple of markers on the police national computer nowadays 😅

I ran it myself for a while and it was fine but I don’t think it liked the local occasional journeys I was using it for at the time and threw its toys out 😂

[NorthernMonkey]

Been pondering on this last night, as you do.

Assuming the engine isn’t toast, which my gut instinct tells me it isn’t, I’d rather do a full refresh including a new camshaft from TPS, new chain and tensioner, new cam belt, oil pick up strainer, the works basically as it’s destined to be Claire’s new car and family runaround alongside the RR SC.

The problem is, I don’t want to go all Billy Big Bollocks with the chequebook only to build it all up and find the bottom end has gone or there’s grooves in the bores due to lumps of metal floating around in the oil, so I’m thinking that unless anyone can tell me why it’s a bad idea, I’ll stick the new pump on with the intact cam follower I’ve got sat here and loosely refit the rocker cover etc with the intention of getting it fired up and having a close listen.

Then, assuming it sounds healthy enough, I can drive it onto the ramp with warmed up oil, drop the sump, clean everything out and start throwing new bits at it. The cam lobe, although showing signs of wear, still feels relatively smooth so five or ten minutes of ticking over to warm everything up isn’t really going to do much more damage than will have been done already being driven daily until the fuel pressure finally dropped too far to continue running.

Any thoughts before I chuck the new pump on when I’ve finished this Peugeot starter motor later this afternoon?? The oil I’ve seen and felt around the top end with the rocker cover off feels clean and oily enough with no grittiness or signs of sparkly bits and the cam lobee themselves are all nice and shiny so I reckon a lot of the particles in the oil will have already been removed on previous services as the wear to the follower has probably occurred over a reasonable period of time.

[SiC]

Presumably the metal on metal would have worn off any hardening on the cam. 

I've always wondered why no one has done this on a severe pump/cam wear failure like this. I presume because it's inevitably a garage fixing it and they would never ship it out the door without doing the cam too. Someone doing exactly what you said probably wouldn't tell anyone else they've done that and kept their fingers crossed when they ship it out. I really wouldn't be surprised if there wasn't a good few cars that have been through the trade and failed, to have a new pump and follower chucked at it...

I think these are cartridge style filter? If it was me, I'd probably pull that and check for glitter in there plus also to see with how well it's filtered that out. If badly glittered then maybe lob another filter back on with fresh oil before the next run. Then it would give a reference point when that is dumped out again how much shiny shite is left floating around+a flush. 

[NorthernMonkey]

14 minutes ago, SiC said:

Presumably the metal on metal would have worn off any hardening on the cam. 

I've always wondered why no one has done this on a severe pump/cam wear failure like this. I presume because it's inevitably a garage fixing it and they would never ship it out the door without doing the cam too. Someone doing exactly what you said probably wouldn't tell anyone else they've done that and kept their fingers crossed when they ship it out. I really wouldn't be surprised if there wasn't a good few cars that have been through the trade and failed, to have a new pump and follower chucked at it...

I think these are cartridge style filter? If it was me, I'd probably pull that and check for glitter in there plus also to see with how well it's filtered that out. If badly glittered then maybe lob another filter back on with fresh oil before the next run. Then it would give a reference point when that is dumped out again how much shiny shite is left floating around+a flush. 

No, I reckon there’s probably a few out there that’s just had a new follower lobbed on then punted through eBay or marketplace.

Excellent point re the filter…I’ll pull it out first but I’ve had a close look at the oil in the housing where I took the vacuum pump out whilst checking for damage and there’s no sign of particles in there.

[Dave_Q]

Sounds fine for test purposes, I think you could probably damage/wear the new follower quite quickly running on a damaged cam but it would be cheap enough to get another new one if needed.

Maybe do it with an oil pressure gauge connected so you can stop the experiment quickly if it's not getting pressure? IE if any of the lost bits of metal are in the pickup pipe.

[SiC]

🤞 the filter on the dirty side has caught all the glitter.

[dome]

Yeah I'd probably pull the filter too and do an oil change with whatever you have to hand and a fresh filter before firing it up.

It'll cost you very little and be cheap preventative maintenance just in case anything has got into the sump.

 

[MrBig]

Has the cap been ground off that lifter or has it broken off? I'd be slightly concerned there is a large piece of it somewhere floating around.

[Dave_Q]

17 minutes ago, MrBig said:

Has the cap been ground off that lifter or has it broken off? I'd be slightly concerned there is a large piece of it somewhere floating around.

They wear, this picture of the stages shows the progress. I assume it's deliberate that the cheap and easily replaceable lifter wears and the cam doesn't (if the lifter is replaced in time)

I reckon there could be bits of the collet/washer from the pump that pinged off but the majority has probably been turned into Forbidden Glitter.

[NorthernMonkey]

9 minutes ago, Dave_Q said:

They wear, this picture of the stages shows the progress. I assume it's deliberate that the cheap and easily replaceable lifter wears and the cam doesn't (if the lifter is replaced in time)

I reckon there could be bits of the collet/washer from the pump that pinged off but the majority has probably been turned into Forbidden Glitter.

I’d like to think mine is at least a 4.5

[Dave_Q]

Just now, NorthernMonkey said:

I’d like to think mine is at least a 4.5

5 or 6, surely

[NorthernMonkey]

31 minutes ago, MrBig said:

Has the cap been ground off that lifter or has it broken off? I'd be slightly concerned there is a large piece of it somewhere floating around.

It’s ground off over a period of time as the remains of the follower is contoured to the cam profile and it was running right up until the pressure provided by what was left of the fuel pump fell below what is required by the ECU.

[NorthernMonkey]

1 minute ago, Dave_Q said:

5 or 6, surely

I didn’t want to boast… 🤭

[NorthernMonkey]

51 minutes ago, dome said:

Yeah I'd probably pull the filter too and do an oil change with whatever you have to hand and a fresh filter before firing it up.

It'll cost you very little and be cheap preventative maintenance just in case anything has got into the sump.

 

You’re all correct of course…just as well this starter motor has been a complete bastard to change and I’ve still got to put everything back in place otherwise I’d have chucked the pump on by now and temptation would have got the better of me.

I’ve ordered a couple of new filters and will do a quick oil change first before testing my mechanical theories in the morning.

You can all blame @dome for being left hanging overnight for the first start up…

[NorthernMonkey]

Sort of update…it’s not looking good.

Checked the filter earlier and everything looks ok so I put the new pump on and refitted the plugs and coils etc.

Unfortunately, it seems to be spinning over far too quickly and doesn’t look to have any compression…this will be confirmed in due course once I find my compression tester following last weeks mammoth tidy up of the tool room…and shows absolutely no interest at all in starting.

I’m now thinking that the horrible noise that @CraigRK’s lad reported as it cut out was possibly the remains of the collet from the end of the fuel pump push rod getting caught up in the cam timing chain when it parted company and has thrown out the timing.

I now need to get it on to the ramp so I can lift it up a bit to start stripping down the top end tomorrow as working on the engine whilst bent over is doing my back and sciatica absolutely no good.

[hairnet]

has mrs monkey said no yet

or not read this yet