MK5 GTI - turbo pressure release + intake manifold motor issues

[VdubEd]

Hi guys,

I'm posting on behalf of a friend who's got a 2004 mk5 Gti. He took it to bill buckle today and was told he needed a new turbo release valve and motor for the intake flapper. They also said there was a fuel pressure issue and suggested replacing the camshafts, which didn't make much sense to me? Can anyone elaborate?

So a couple quick questions:

1) They quoted 1600 to do the work does this sound about right (excluding camshaft)?
2) is it worth getting aftermarket / performance replacements
3) any recommendations for an alternative mechanic in Sydney's lower north shore / city area. (preferably cheaper) I have a mk1 and do all my own work on it, if I can't do it it goes to Camden Gti, so don't really know any decent mechanics in the area.

Thanks, ed

[Lucas_R]

I assume that "turbo release valve" means the divertor valve? If so, then this is a very common part to fail on these cars. New ones can be purchased from Dubaddiction.com.au

Can't help you with the intake flapper??

The fuel pressure one is also common. These engines have a high pressure fuel pump (commonly referred to as a HPFP) which runs via a lobe on the intake camshaft. There is a part which "wears out" over time and should be replaced every 60,000km or so. If this is not replaced, then damage to the actual pump and camshaft is possible.

[kryten2001]

Hi guys,

I'm posting on behalf of a friend who's got a 2004 mk5 Gti. He took it to bill buckle today and was told he needed a new turbo release valve and motor for the intake flapper. They also said there was a fuel pressure issue and suggested replacing the camshafts, which didn't make much sense to me? Can anyone elaborate?

So a couple quick questions:

1) They quoted 1600 to do the work does this sound about right (excluding camshaft)?
2) is it worth getting aftermarket / performance replacements
3) any recommendations for an alternative mechanic in Sydney's lower north shore / city area. (preferably cheaper) I have a mk1 and do all my own work on it, if I can't do it it goes to Camden Gti, so don't really know any decent mechanics in the area.

Thanks, ed

I'm assuming (but could be wrong?) that the Turbo Release valve is the diverter valve... The old rubber sealed ones were prone to failure and have since been replaced with a far better revision. These are worth about $150 if I recall... Bit of a bugger of a job on a regular Mk5, so probably 45 mins labour.

Flapper motor going isn't absolutely a drop-dead issue. Just depends. If the flapper is stuck open (which I assume it is?) then it's not really a do or die. A lot of people out there actually remove them (I wouldn't recommend it though).

There is a performance aftermarket DV, but frankly I'd just stick with the new revised one from VW. Nothing wrong with it, miles better than the old one.

That fuel pressure issue should be sending off huge warning signs. The early Mk5's (Up till late 2006/early 2007) are having massive issues due to wearing camshafts/broken fuel pumps because of the density of the alloy used in the cam lobes. If you're getting low fuel or fuel cuts, you could be in for a mountain of pain there..

---------- Post added at 04:03 PM ---------- Previous post was at 04:02 PM ----------

I assume that "turbo release valve" means the divertor valve? If so, then this is a very common part to fail on these cars. New ones can be purchased from Dubaddiction.com.au

Can't help you with the intake flapper??

The fuel pressure one is also common. These engines have a high pressure fuel pump (commonly referred to as a HPFP) which runs via a lobe on the intake camshaft. There is a part which "wears out" over time and should be replaced every 60,000km or so. If this is not replaced, then damage to the actual pump and camshaft is possible.

You beat me to it!

[VdubEd]

Thanks guys, very helpful. I literally just repeated exactly what I was told on the phone... So assuming it's the diverter valve, is it worth buying the valve and doing it myself, or is it better left to the pro's (45 mins sounds like a piece of cake?) And what's involved in the inlet flapper motor?

With the cam sounds like he would want to get that sorted sooner, than later? When you say 'a mountains of trouble'... That's a bit worrying... How bad are we talking and what sort of costs would we be involved to get that sorted (assuming the fuel pump is still good)?

Thanks again

[VdubEd]

So had a quick look online, looks like replacing the cam follower, diverter valve and flapper motor are all fairly easy things to do on a Sunday afternoon, would anyone disagree?

[kryten2001]

Thanks guys, very helpful. I literally just repeated exactly what I was told on the phone... So assuming it's the diverter valve, is it worth buying the valve and doing it myself, or is it better left to the pro's (45 mins sounds like a piece of cake?) And what's involved in the inlet flapper motor?

With the cam sounds like he would want to get that sorted sooner, than later? When you say 'a mountains of trouble'... That's a bit worrying... How bad are we talking and what sort of costs would we be involved to get that sorted (assuming the fuel pump is still good)?

Thanks again

First, the diverter valve....

I've got a Pirelli, and the DV is on the front of the engine. To replace it is dead easy, it's a 10 min job. On the regular Mk5, its on the rear of the engine so access to it is from underneath the car. It's not a difficult job, just a little fiddly as you have to do it lying prone with the car jacked up on BOTH sides using car stands... Not tough, just fiddly.

Now the cam follower issue is a very different story.

What you need to do is inspect your old one. If its worn through, then you are in big trouble. That is, this is assuming your low fuel is being caused by this (it may not be).

First thing you want to do is inspect the follower. You can do this by removing the existing fuel pump and then simply pull out the follower. If the follower has a hole right through it, you're screwed. Most likely your cam lobe is worn down, and your fuel pump is probably also stuffed.

The cam follower is a very simple little thing that sits between the fuel pump and the cam to prevent the plunger/pump activator on the fuel pump from having to actually sit on the cam. If the follower fails, then the plunger on the pump comes into direct contact with the cam - badly damaging the both of them.

It's not DEFINATE that your low pressure fuelling is being caused by a failed cam follower, but it's also the most likely cause. Fortunately it's a very easy thing to verify, but if you see a hole in your cam follower you may as well break out a bottle of scotch and drown your sorrows as replacing the cam and pump will set you back some serious coin.

If this has happened to you though, drop me a line and I can probably help you out with a fuel pump. I have a near brand new OEM one.

The cam's are worth about $1500, and there's probably about a day's labour.

Before you panic though, take a look at that cam follower.

I would be interested to know how your mechanic knew you had low fuel pressure. Did he log the car?

Good luck.

[VdubEd]

Thanks kryten. I'll definitely let you know how I go. It's not my car and my mate's still deciding whether he wants to let me loose it, I suspect he will so hopefully we'll get onto it next weekend.., as long as a few parts for my mk1 haven't arrived.... In which case that might take precedence

Bill buckle only recommend he changed the cam lobe soon, so guessing its not sending any major alarms bells ringing yet.

Cheers!

[kryten2001]

Thanks kryten. I'll definitely let you know how I go. It's not my car and my mate's still deciding whether he wants to let me loose it, I suspect he will so hopefully we'll get onto it next weekend.., as long as a few parts for my mk1 haven't arrived.... In which case that might take precedence

Bill buckle only recommend he changed the cam lobe soon, so guessing its not sending any major alarms bells ringing yet.

Cheers!

Changing the cam lobe is a pretty big warning signal!

Cam lobes should not wear out so quickly unless there is another issue at play here. There could also be other history you're not aware of. For example, the cam follower could have been replaced recently after an older one had worn through - but the underlying damage could still be there. Many people see a damaged follower, so they simply replace it. The underlying damage is still there though.. Think go a cam follower as a condom - nothing more. Replacing one that's broken doesn't mean you've not already had the damage done

This cam follower issue is a storm in a teacup for many, but for an older car that's done more than 80,000kms with the cam follower NEVER changed, your mate could be one of the many who have had serious damaged caused by the a failed follower.

The newer Mk6's don't have this problem as the entire fuel delivery hardware is different... Cars that have been extremely heavily modified (like mine) need to have their followers checked every 15-20,000kmh.

It's not the end of the world (worse failures can occur) it's just a real pain. This is why I check mine with every other oil change and always keep a spare on hand if I need to swap one out. I checked my first follower at around 5,000kms (like I say, it's a very heavily modified car) and the material on the bottom of the follower (that covers the substrate) had just started to show signs of wearing off.

When a follower fails, the cam/fuel pump rub straight through the outer material, through the substrate and literally wear a huge hole though the follower. When this happens the follower is no more than a tube, and the cam lobe/fuel pump are in direct contact with each other. This then causes wear, and the fuel pump starts working less effectively. Fuel pressure then drops, getting progressively worse until fuel cuts start occurring - first at high RPM and then eventually at midrange.

[snerlo]

Interesting hearing all the talk on the cam follower and fuel pump issue. I just picked my turbo Jetta up from having this very issue resolved, although it was the camshaft and fuel pump. Not cheap, let me assure you. In conjunction with a faulty turbo solenoid, geese, the cars different with it all fixed. And the motor doesn't sound like a diesel anymore!

[VdubEd]

Hi Guys, spoke to my mate again this is the exact part number they gave him for the faulty valve that we have been assuming is the diverter valve? I had a quick look online and couldn't find anything can anyone advise?:

Pressure Release Valve
Part number - O6H145710D
Issue – Torn

Thanks, Ed

[kryten2001]

Hi Guys, spoke to my mate again this is the exact part number they gave him for the faulty valve that we have been assuming is the diverter valve? I had a quick look online and couldn't find anything can anyone advise?:

Pressure Release Valve
Part number - O6H145710D
Issue – Torn

Thanks, Ed

The number at the front is a 0 (zero) and not an O (Orange)

That part number is correct, it's the new version.

[VdubEd]

Too easy thanks again!

[thezoneR32]

The cam's are worth about $1500, and there's probably about a day's labour.

Hey Kryten,

Are you talking about the intake cam? Are you sure they cost this much?

[kryten2001]

Hey Kryten,

Are you talking about the intake cam? Are you sure they cost this much?

Not sure of its exact name, but it's the cam that pushes on the fuel pump's arm (via the cam follower).

I could of off base, but yes I do recall reading the somewhere - and there's quite a bit of labour involved.

The fuel pumps are usually shot as well - and they're worth about $800...

[thezoneR32]

Not sure of its exact name, but it's the cam that pushes on the fuel pump's arm (via the cam follower).

I could of off base, but yes I do recall reading the somewhere - and there's quite a bit of labour involved.

The fuel pumps are usually shot as well - and they're worth about $800...

Well the intake cam kit (rev b) you can get from ECS tuning for $450 + shipping (I picked a brand new one up of ebay for $125 but that was a fluke). And a HPFP you can get from HPFP.com for about $500 + shipping. So I dont think its all that bad.