Car cut out. Injectors? Fuel Pump? Please help!

**lorda4** · 19-03-2018,12:12 PM

Hi all,

Hoping someone knowledgeable can help out. My 2007 2.0TDI BKP Passat estate cut out this morning about a mile from my house. For a few seconds it was like a misfire so I dropped a gear and tried to rev, it then cut out and I had to roll to a stop. Tried cranking but no joy, would run at all. There are no engine warning lights.

AA man came to recover me - He sprayed some starting fluid into the intake and got me to crank the car - it started but was running lumpy and he suggested an injector had gone.

I have used VCDS to run a scan but the only errors are boost pressure regulator, and mass air flow sensor from when the intercooler failed last week, and error about the parking brake from when it failed this week (yes, all of this has happened in the last 2 weeks

). Intercooler is replaced and car has done around 450miles since then, and parking brake motor is on its way.

I have done a bit of searching and from what I can see, it may well be an injector issue, but should I expect a fault code and how do I work out which one has failed? Could it be the fuel pump, and is there any easy way to tell?

I also started reading the threads on injector recalls but would this still apply to the car? My service booklet has a note about recall 23H9 carried out in 2012 - was this the injector recall?

Any help much appreciated.

**Rob69** · 19-03-2018,02:13 PM

check the V157 air intake throttle flap is not stuck closed, this is upstream of the EGR valve. Injector fault would show up in vcds or can be checked in measuring blocks

**DMitch16** · 19-03-2018,02:37 PM

Firstly - The Intercooler failed? How did that happen, as it is only a radiator type cooler for air? Was it leaking / punctured?

23H9 is the injector recall so you should have the updated injector version and replacement loom (the recall covers both). Although it is possible for the newer versions to fail (I have only heard of a very small few) and yes an injector fault code or possible a few of them would be expected if this had happened. If I recall when this happened to a friend who had injector failure pre recall, the car could not be restarted at all.

The in tank fuel pumps can cause the car to choke and cut out in a similar way. This is especially true if the fuel level is always lower than higher in the tank as these pumps are designed for submersible use and dry out if the fuel is always minimal. This causes the motors to operate hotter than they were designed and fall sooner (they are only little 12v DC barrel motors - not much to them and the brushes wear out eventually too). If your mileage is significant then it may be the pump motor has mostly given up or about to stop altogether and a replacement of the pump unit for these models once into the 100k range is common. A great deal of B6 owners have had an In Tank Fuel Pump change. I would remove the pump unit and test it on the bench (in a plastic tray / bucket partly filled with diesel - watch out for sudden fuel gushes if it is working).

Also save your VCDS log, clear the codes to eliminate any older, no longer relevant codes that may be hanging about from earlier issues and rescan.

Then (before Gazwould mentions it) - BKP is an at risk motor for the Oil Pump Drive failure if this has not already been attended to.

**DMitch16** · 19-03-2018,02:49 PM

Originally Posted by Rob69

check the V157 air intake throttle flap is not stuck closed, this is upstream of the EGR valve. Injector fault would show up in vcds or can be checked in measuring blocks

Ah, a gummed up or failed EGR / Anti Shudder Valve Flap unit issue (there's no throttle on a B6 TDI as such) - could be but if the motor was a problem it should give a V157 related code should it not?

**lorda4** · 19-03-2018,03:08 PM

Thanks for this.

The intercooler was leaking - where the plastic intake pipe joins the metal radiator there was a rubber seal that had popped out. It's frustrating as this was only replaced a couple of years ago, however it was a pattern part so perhaps that is why - there haven't been any overboosting issues or such like. When it happened, the car started overfueling as less air was going in, and it eventually went into limp home mode. Replaced the intercooler with a hella one and it was fine.

regarding the fuel pump, im on 127200 miles, so a fair amount of milage - from searching I have seen other have had a fuel pump issue without any error codes hence my thinking it could be this but was concerned with what the AA man has advised it might be. FYI, I Fill to the brim, empty then refill - so it will spend some time unsubmerged.

I have done the KMB balance shaft as preventative maintainace about 8000 miles ago - the hex key in the orignial was worn but I reckon had a fair amount of life left - it certainly wouldnt have spun for a long time.

I take it just hook up the pump out of the tank to 12v and see what happens?

I will take a look at the flap, but as noted no errors to suggest this at this point

**lorda4** · 19-03-2018,03:26 PM

Originally Posted by lorda4

I have done the KMB balance shaft as preventative maintainace about 8000 miles ago - the hex key in the orignial was worn but I reckon had a fair amount of life left - it certainly wouldnt have spun for a long time.

To clarify, it hadn't spun, but it would have been many more miles before it got to that point.

**Rob69** · 19-03-2018,04:22 PM

I've had two V157's fail on pd 1.9's and neither threw a code specific to the V157, one threw nothing, the second brought on the EML and logged an EGR code.

Originally Posted by DMitch16

Ah, a gummed up or failed EGR / Anti Shudder Valve Flap unit issue (there's no throttle on a B6 TDI as such) - could be but if the motor was a problem it should give a V157 related code should it not?

**DMitch16** · 19-03-2018,04:43 PM

Interesting - thanks Rob69.

**PassatMan61** · 19-03-2018,06:32 PM

I think I share the sticking air intake flap problem on a Passat B6 BKP engine. What is the solution please? Mike T.

**lorda4** · 20-03-2018,11:50 AM

I haven't had a look at the car yet - it was far too cold yesterday. I want to test the fuel pump first of all. Does anyone think I would have an issue disconnecting the fuel supply hose from the pump in situ and replacing with a bit of hose that I could catch any fuel in a bucket, then crank the engine to see if any fuel is pumped? Would this cause any issues with the fuel system (air etc)?