2.5tdi help needed

Mat197

Mat197

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Afternoon all

Look on the forum a lot but this is my first post so go easy :grin:.

I have a 2.5tdi cabriolet 05 plate and last few days I've had trouble starting it cold and hot. Today when starting I had to crank it for a while then it eventually started but When driving it was also hesitant,it also now has the battery light on but this I'm assuming is down to cranking the engine.ive checked the fuel lines for any cracks etc but all seems ok.

I'm thinking it's a fuel pump issue but any input would be appreciated.

Many thanks mat
 
That did cross my mind but it but it made me think something else was an issue with it running rough and hesitanting once started?

Thanks
 
Could be a number of things, battery light on the dash means no charge from the alternator. Best look into it because it means that that the engine will not get the cranking power from the battery and the pas aux belt tensioner might need rebuilding...
 
Have you had anyone borrow it who may have accidentally put petrol in it?

Ask how I know about this problem :haudrauf:
 
Thanks for the replies .Haha I hope not And will check the battery/alternator also to be sure but I did do the Cambelt and aux belts about 2k miles ago and all looked in good order.done a bit more digging and I can no longer hear the fuel pump come on for few secs when ignition is on so thinking that this may be it?
 
Hi

Hoping someone can give me a bit of help with this plzzz.spend all day in the rain changed the fuel filter and lines as perished.got it bleed up and running but still running like a bag of spanners.on tick over the turbo actuator is operating up and down and won't rev cleanly.anyone any ideas before I give up haha.also engine management light on.

Thanks
 
Cheers for replys,not checked for codes yet as I don't have the kit or scanner unfortunately but looks like it's next thing to do.and I did think that but it's the same fault as had before I did the work stumped to be honest
 
With these having so many sensor etc. It's extremely difficult to know without fault codes your fault could be any number of things but reading the codes will help you / us narrow it down . The diesel pumps do give up which I hope isn't the fault but I would go there first .
 
Update just plugged in a reader and coming up with code p2102 which Is listed as the throttle actuator unit which kinda makes sense.has anyone got any tips or past experiences with this fault?

Thanks in advance
 
Check the operation of the flap motor on the intake manifold. If you are standing in front looking into the engine bay its on the right at the front of the engine on the vertical pipe from the intercooler to the inlet manifold. Switch the key on and off and watch it opening and closing properly. If it isn't opening it won't start.
 
Just had it off checked motor and little sprockets inside and all ok also opens when ignition is on so thinking maybe it's the electronics inside the throttle body itself ..
 
If the flap is opening then you can rule that out. Is your egr valve still connected? You could try blanking it off to see if that helps. A jammed open egr can hamper starting and won't throw up a code.
 
I did have the erg blanked off but decided to fit it back as was bringing on the engine management light but I do know it's clean and operates ok.packed up now as the battery has finally give out,will get a new one as it seems to be very tired even when charged all night a bit of cranking it falls on its **** wouldn't even bring the main computer screen on the dash on in the end.not looked at coolant temp but worth ago.may have to admit defeat with this one
 
It may be a charge issue , the central electrics rely on the charge system to be optimised by the charge , get the alternator tested too that could have killed the battery in the first instance
 
Yeah will do the battery looks fairly old too so definitely worth changing before I do anything else now.
 
I see an earlier post mentioned you couldn't hear the lift pump operating from the tank. You can check it by slackening the bleed screw on the top of the diesel filter - then turn the key and just hit the starter for a second. The pump should spurt fuel from the bleed hole at the filter. If not then the pump isn't lifting the fuel from the tank. Use plenty of rags to catch any fuel spill from the filter bleed screw. I just hope its not the injector pump failing as this is a very common fault.
 
hi abyrne I have checked the lift pump by putting a supply directly to the fuse and also checked it operates when cranking which it does so my gut feeling is now is it's the main fuel pump.its in a Audi specialist now as I've run out of ideas and things to check so hopefully hear back today.cheers
 
Haha I know dreading the phone call but knowing my luck it will be that.
 
Heard from the Audi specialist on Yesterday and he thinks it's the pump with the symptoms and it threw up a code on from the pump (can't remember the exact code) so he said he would remove and send of for testing and that's all I know so far.im going to ring first thing in the morning but unfortunately does look like it's the dreaded fuel pump :(.will update when know more.cheers
 
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I was afraid it might be. Unfortunately if it does show up a fault then the pump will need reconditioned at a cost of around £600 + VAT and then labour for removal and refitting. The ECU on top of the pump is the achilles heel usually. The heat and cool cycles break the soldered joints and the pumps often fail without warning. There are cheaper fixes offered by various companies whereby they repair your own ecu but whilst they will get your car running they are rarely a great success. Rough running, hard starting etc. These pumps are very precise instruments that need careful calibration using specialist equipment.
 
Hi yeah been doing a bit of research and does seem like the ecu part is the weak link and mechanical parts hold up. Should know the damage later today haha but to be honest I'm happy for it just to be sorted now as spent a lot of time myself chasing the fault.
 
Update,just heard back and the pump is gone so quoted a price of £1200 which Is for a re placement pump (1 year warranty),testing of old pump and fitting.what do u guys think re the price? Cheers
 
The reconditioned pump will be around £750 Inc vat, maybe more depending on what condition yours is in. It's a good days work for a garage to remove the pump and refit it. The front has to be pulled into the service position to get it off. Then you need specialist equipment to match the new pump to the immobiliser in the car and after getting it running the pump timing needs set. They are getting well enough paid but not everyone has the kit to do this job properly.
 
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Ok cheers told them to go ahead with the work was just a kick in the teeth but just one of them things I suppose.hopefully touch wood now this is done I should get a good few years from the old girl as all the big jobs that are issues have been done.
 
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That's unfortunate but that seems to be the main failure point on the 2.5 tdi's . As you say it will serve you well for a few years yet.
 
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Car back today with its new pump seems to be running nice and very little smoke under heavy acceleration unlike before.thanks everyone for the help.

Cheers
 
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