Diesel Pump Advice

[Christophski]

So not an Audi but this is the best forum around from my experience so here goes...

So as most of you will probably know my van has been in limp mode for quite a few months. (10 months) Have done pretty much everything to it with a lack of any real codes being thrown for my van (VW T4 99 reg 102bhp 2.5tdi)

So last week VAGcom showed my pump timing was out so a mechanic mate set it up this weekend just been with DTI guages so it was spot on. Seems the locking collar on the adjuster screw (?) was not in and it was loose so pump timing was all over the place. Anyway it has run spot on for nearly 100 miles now but then on the way home from work last night it started running how it did before, basically not boosting. I checked the locking plate was in and the adjuster screw on the pump was tight and it all still is.

So my question is the following: If the internals of the pump are ruined will it do the above even with this screw done up tightly? Will the internals of a ruined pump make it run badly even if the timing hasnt slipped etc? I know I need to plug it in to VAGcom again to check the timing on the pump but my suspicion is the pump needs a rebuild and then setting up with the DTI guages again.

Basically will a pump run ok for a bit then throw itself out again if it is worn? Even without the timing belts slipping?

Any advice from the mechanics?

Thanks
Chris

[Christophski]

Any advice anyone?

[Monkeymagic]

i work on loads of these if its able to tick over get timing plotted you don't need a dti to set them up. the locking plate you refer to is only there to lock pump at tdc. never ever run engine with the plate removed and 10mm bolt tightened. if basic timing set up van should run although low on power. all adjustment is done by loosening pump pulley very find adjust can be done on lower belt tension. both ajt and acv engines have good diagnostic ability. if i was working on it if check timing plot boost and measure maf readings save guessing.

[Christophski]

Thanks, yes it idles and runs fine but it doesnt do boost it just goes flat. Most annoying! It was set up and was absolutely fine but then its just died to no boost after 90 miles. Could it be the internals of the pump are screwed and making it do this? As the locking plate is still in and the 10mm bolt nice and tight so im expecting it all to be at tdc. Is it possible for the internals of the pump to be screwed and do this?

[re2500]

It may be that because your van has not been running or boosting right for so long. When it has been running right for the last 100miles, the extra boost may have caused a small boost leak/split hose?
Are you getting much black smoke at WOT?

[Christophski]

Im getting more than when it boosts ok but not loads. All the vac hoses have been replaced for silicon ones already. I did it so I could eliminate this from teh problem. Was the first thing I did.

[Monkeymagic]

i hve seen a few reasons for lowq boost ranging from badly adjusted actuator. split or incorrectly plumbed vac hoses and failed maf's. find someone with vcds and within 10 mins and a few simple checks you should get your answer. good luck