T5 2.5tdi 130 Starting problems again..!

Thanks you guys. I have the pump tested today and see what the outcome is.All of the sugetions make sens.

Fishvan wrote: Hi,Tuxxy132.I got my van in 2008,loved it from day one,but the last 4 months were no fun. My problems seems to be intermittend and nobody at VW South Africa can help me, or lets say wants to help.The turbo is fine.It is almost as if there is a fuel shortage. When the motor is running and there is no load, it is smoking a lot.When I pull of there is a bit less smoke and then it goes away. When the motor is cold it seems to be fine.

Fishvan my fuelling was not brill I don't no exact mpg but I replaced massair flow sensor at same time and am getting about 400 miles to £65 which I am happy with but on another note the van is back in garage after braked own this weekend AA think turbo problem but no word from garage yet only had my van 3 weeks and it's been off the road 2 weeks of them with problems starting to wonder weater the 2.5 tdi t5 was a good choose :(

had van back from garage today and turns out it was as simple as one of the fuel lines not being connected proplery said as soon as he pushed it back in to place he feelt it click in to place and van had started first time from cold since :)  

Cheers T5 TDI, Looks like i have some more reading to do! Thought i had just about cracked the common rail thing! Now you throw something completely different at me, my poor old brain can't cope! Thanks for the link, holy shit i was way out! But does the same sort of thing not happen if internal seals / control oil circuit have letby?Cheers Mark  

Gents I’m new to T5’s so I’m on a steep learning curve here! But having read this thread I’ve experienced similar issue’s with other van’s mainly Vito’s.

The biggest problems with common rail diesels is the very high pressure (250 Bar plus) they need to run. The injector needs that pressure to open and also to atomise the fuel. It opens the injector buy creating a differential pressure across the injector creating lift against a spring a very strong spring! It also needs that pressure to atomise the fuel.

It creates that differential pressure by opening the solenoid valve on top of the injector (ECU command) Now here’s the rub if one of these lets by (Not seated properly) it takes longer to build the pressure. More cranking, remember we are only talking small amounts of diesel. But it makes a difference!

I experienced this; Van would restart first time if only left for a short time! However, if left all night it would be hard to start but once running was fine. The pressure decayed in the rail over time due to let by! I went down the same routes air in the system, new battery, fuel pipes, pumps and clamping things! And no fault codes!!!!

I would look at getting a leak of test done. Don’t know the procedure for the T5 so roughly, there should be small pipes coming of the injector at the top by the solenoid running back to the fuel supply system. Remove these from the injector, clamp off the other end fit small plastic pipes to the injector so you can see the amount of leak off. (You can buy a set of pipes that are marked / calibrated so you can measure the amount of leak off. VW will have a given value for a set time of cranking). Disconnect the cam shaft sensor so the van will not start and crank for given time. Measure leak off! (Don’t take these instructions as gospel; I’ve not done a T5)  

Probably best to take it to a specialist diesel centre as they will also be able to overhaul the offending injector / injectors. The dealer will be able to do the test, but he will send the injector away for overhaul or tell you, a new one is needed. They don’t have the tooling / machines to do the injector overhaul themselves.   

I managed to diagnose mine myself and got it overhauled locally at a Bosch centre, roughly £80 for the parts and labour! Mine was bad and the leak of test showed clearly which injector it was.

Hope this is of help!

Mark

 

 

Hi Jon,

The van has gone now so not sure on whether what I did cured the problem permanently, but I tried everything including the glow plugs and that isn't make any difference. I think the problem with mine was down to either trapped air in the fuel filter/line somewhere or it was a dodgy connection on a sensor somewhere, because I dropped the fuel tank and did that little pressure test and at the same time I had a fiddle with all the wires under the engine and it worked fine after that, so it was one or the other?? Good luck mate...

when you were down there did you open the crankshaft position sensor plug on front of bellhousing/engine block joint and check for burning on contacts?
It will probably throw a fault code for sensor if it is an offender though.
would cause poor starting you describe.

Or a leak between the turbo and the exhaust manifold.  I think there is a thread on here about someone making some better manifolds for the R5 (2.5l) engines.

Update...