ED30 - running issues

[Dave J]

Hi all,

Had the Ed30 out today and had to take the long way home due to ridiculous amounts of roadworks in my town, and the M4 diversions were playing havoc with the traffic.
Gave the car a decent run and it behaved faultlessly until I did a 2nd gear pull, after which it was stuttering in all gears - power came and went.

Got off the main road when I was nearly home - turned the car off and back on to hopefully reset anything, and the car did start cleanly, but would die immediately (it's a DSG). Left it a few minutes, and it did get to a lumpish idle and got it moving again, but again - still very jerky, on/off with the power vs. throttle position.

No EML, no flashing PRDNS (that I have heard of with bad mechatronics on the DSG).

Car is a 2008 DSG ED30, has R8 coils, VWR intake, Revo map, Loba HPFP. Done very few miles since the last service. Has had new DV, PCV well before they were due. Of course, they could be the issue, and at least I have a new DV I can try tomorrow.

Can't see obvious evidence of boost hoses being blown off.

Any ideas? I have Vagcom, so will scan the car tomorrow.

Anyone experienced similar?

[GVK]

Check you haven't blown an intercooler pipe off or got a split in one, they play havoc if they leak.
The left one can be difficult to see where it goes on the intercooler.

[Dave J]

Thanks GVK - this was my initial thoughts, but couldn't see anything obvious. Will strip a few parts down tomorrow to see what I can find...

[pudding]

Does unplugging the MAF improve matters?

[Dave J]

Hi Pudding - no, it made no difference. They still think it is the in tank fuel pump...

[pudding]

That is certainly a possibility.  It's worth logging it to see if requested pressures meet the targets.  Can you hear the in-tank pump at all?  A healthy one is barely audible. Worth changing the fuel filter if it hasn't been done in a few years.  It's not part of the service schedule but when they clog up, it's more load on the pump.

If your lift pump is the original, VW did update it some years ago.  The original pump was fully enclosed and was prone to over heating, especially when the tank was quite low. The revised one has no lid to help with cooling.

In my experience though, tired lift pumps generally only affect the boost performance when they can't keep up with the demand, but are OK at urban speeds. 

GVK's suggestion is a good one.  Check for oil drips around the boost pipe connections.  It would have to be a very major boost leak to cause that kind of rough & jerky running at low revs though.

As always though, first port of call is a scan for fault codes and/or anything obvious amiss in the measuring blocks.  The EML pretty much only comes on for legislative emissions reasons, such as below threshold catalyst efficiency, dead O2 sensor, dead MAF, hard misfires from bad injectors etc....anything that pollutes the trees and pheasants and upsets Brussels, basically.  Otherwise the engine can run like a constipated Camel and the ECU is like "Eh? Nothing to see here, move along".  Annoying!

As an additional thought, switch the Revo to stock mode if you have the SPS.  I'm not doubting the software as it's super reliable, but it doesn't hurt to get the engine back to a stock baseline during troubleshooting.

[Dave J]

Thanks Pudding - really appreciate it! I can't hear the in-tank pump - never really have, whereas on my old mkiv 1.8t you could hear it prime when you opened the drivers door.
I did have the fuel filter changed a few years back as preventative maintenance, along with R8 coilpacks. Car is always run on V-power, so it is on about the best. 

I've been back through my records as the car did break down once at work many years ago, just kept stalling in the same way. However, that time the EML did come on, whereas this time it didn't. Just found the invoice - 2014 (near enough exactly 40k miles ago) - new in tank pump and sensor at VW - the pump they fitted was 1K0 919 051 DB. This was all before the Revo map and HPFP. The HPFP should be good as it is a Loba, unless it has chewed in to the camshaft!

I did check all boost pipes as far as I could see, and seemed all ok.

At least my vagcom scan came up with the same codes as the first garage did when it was recovered to them. I'm not quite advanced enough as a user to know where to go with the measuring blocks, but the car is away now, and apparently sorted and I shall collect tomorrow. Hoping all ok!

I do have the SPS - I expect I will have to reset the map, as I would have thought they would have disconnected the battery when working on the fuel system.

[Dave J]

Well, I got the car back yesterday. Was told it was the MAF - weird when unplugging it made no difference.

Still, new MAF fitted and it seems ok on the short run back - time will tell when I take it out at the weekend for a decent drive & a fresh tank of V-Power...

[pudding]

That sounds promising.  These ECUs take ages to adapt so give it plenty of miles before calling it a fix.

What I like to do with a new MAF is pull the battery for an hour (or short the + and - wires together to dump residual capacitive charge) which forces the ECU to start over.  The daily 'pre-flight checks' are performed every time you turn the ignition on. You can hear the throttle flapping about. If the ECU doesn't like the MAF signal, or anything else for that matter at that point, it just runs in substitute mode, as best it can.   It will still run OK with a surprising amount of sensors disconnected!

MAFs are funny things.  I'm on my 4th after 7 years/85K miles.  2 got destroyed with aftermarket filters (another reason why I dislike them!), and the 3rd just died of old age.  4th was fitted 2 weeks ago with no stand out clues, but it certainly runs better.  None of the 3 knackered ones responded to cleaning, they rarely do.

[GVK]

Missed this thread, so it was a MAF , interesting to know the fault code as boost leaks can give a MAF code too.

[Dave J]

I'm so glad I got my VCDS / Vagcom cable on a group buy in mkivs.net - it has been well worth it. This code was P2279, I think, and could have been fuelling issues, boost leak, timing, or goodness knows what else.
Definitely couldn't see any hose leaks, and did pay real attention to the one off the back of the block as recommended.

Touch-wood - sorted for now...

[GVK]

I had to pay £225 for mine and it only works on 3 cars, I have OBD eleven on phone which i use regurlarly, and a normal Foxwell scan tool. Which works on anything.

[Dave J]

So, the car broke again last Tuesday. Exact same issues - no power, then power, then nothing. At one point in first gear, foot to the floor, it was jerking and I seriously thought it was going to stop altogether.

I was further away from home this time, and no chance of limping it home in rush hour. Idle was erratic, hunting, and struggled to cleanly get over 2k rpm.

Called the RAC - what an absolute joke. Said a patrol would be three hours. After waiting over two, I had a call saying they felt the car needed to be recovered as they would be unlikely to fix it at the roadside. That would be another two hours. So, my call went in to them at 5:50pm, and I was recovered at 11:20...!

Needless to say, RAC membership is being cancelled. The car went back to the garage who replaced the MAF last time, and diagnosed it had failed. 5 weeks, and less than 500 miles! They think my VWR intake may have put stress on it as the rubber tie that secured the intake has perished and fallen off.

Time will tell if all is ok now they have secured it and replaced with another genuine MAF.

Tempted to bin the intake and revert to the standard engine cover...

[pudding]

The AA are the same.  Years ago I rang them and told them to send a flatbed truck as the engine had blown (not my current car!), but nope, "our engineer has to come out and assess it first".  "Erm, there's a hole in the block, oil all over the floor and it won't crank over". "I will pass that information on sir"  Effin useless. They really don't believe/trust the customer's advice do they    So yeah, the engineer comes out, takes one look under the bonnet: "Yeah it's dead, I'll call a recovery truck" 

I was going to say, odd that a genuine MAF has died already, but then I remember you have an aftermarket intake.

The first half of this video illustrates perfectly why I don't like aftermarket filters, aside from the terrible fit of some of them