injector loom test Mk1 1.9 TDI

[cravenbiker]

I think that i know the answer to this but is there a way of testing that the loom is the cause of poor start up, loss of power before turbo kicks in and shuddery turn off? bearing in mind that i just did a turbo replacement i thought that it could be a case of an air leak somewhere but after reading on here that the loom could be a cause of poor start i thought id explore other avenues.

Thanks 

[johnnyroper]

Has a mark 1 from 99 got a loom? Thought that was VE engine and not PD?

As for testing donââ,¬â,,¢t really think there is a test as such apart from checking the injection deviation but that does not prove itââ,¬â,,¢s a loom fault just gives indication of cylinder performance

[cravenbiker]

Has a mark 1 from 99 got a loom? Thought that was VE engine and not PD?

To be honest I'm still in the very early stages of working out how this engine works so I'm not sure. I'm no mechanic as you have probably realised by now but am trying to fix the problems through necessity. am i right in thinking that injector pump working off cam belt = VE = No injector loom needed and the PD has no pump but the injectors work on there own with DC?

[cravenbiker]

OK, getting a better understanding of how the fuel pump works now . found a useful video for anyone else that is confused about injector pumps and how they get the timing for the injectors

not sure if allowed to post the link here but found it on your=tube under - BOSCH VE-Pump Operation

[johnnyroper]

VE is conventional injector pump delivering HP fuel to each injector at correct time, timing is adjustable to a certain extent by rotating pump but also something can be done with VCDS.
PD has a tandem pump driven off camshaft that delivers constant pressure to fuel injectors which then greatly increase pressure as they are driven by the cam shaft. The ECU fires the injector hence the loom.

[cravenbiker]

VE is conventional injector pump delivering HP fuel to each injector at correct time, timing is adjustable to a certain extent by rotating pump but also something can be done with VCDS.
PD has a tandem pump driven off camshaft that delivers constant pressure to fuel injectors which then greatly increase pressure as they are driven by the cam shaft. The ECU fires the injector hence the loom.

beautifully explained! Thank you. so the PD have injectors that create more pressure themselves with come sort of internal pump?

[johnnyroper]

Yes exactly that.
PD stands for pump deuse, they are also know as unit injectors because they are a pump aswell.
The cam operating the rocker which presses the plunger in and out creates pressure. The solenoid just opens them when cylinder is on firing stroke.


https://mauriciolemus.com/install_pd_injector_diagram.php

[cravenbiker]

thanks again Johnny, I'm glad that i didn't have to down that road!

couldn't open that page without paying for account but will have a look for a similar diagram.

T