Looking for some info on the high pressure injector pumps used on the 300tdi. I have just changed my old high mileage engine for a nice low mileage engine that I have refreshed.

What I need to know is this. The pump on my old engine has one multi plug attached to the top of the pump and then a single plug down next to where the fuel lines exit the pump. The new pump on the engine I am using has the same multi plug on the top but also a second multi plug where the other pump has a single connector.

What is the difference between theses pumps? What do the connectors do to the pump?. Do I need to swap pumps around or is there a work around?

The plug on top is egr throttle sensor - not required for it to run. The one at the back of the pump is the stop solenoid. Your new engine has an anti tamper solenoid your old engine has the standard "one wire" solenoid. Mechanically I think they are interchangeable. Information given on this subject on here is sparse as it basically telling people how to steal cars.

Ah right ok. That will explain a lot. So I should be able to remove the multi plug stop solenoid and retrofit the single wire one. Or could I use the multi plug loom and just feed it a 12v feed over the correct pin if I can find out what one it should be?

Don't think you can just put 12v on the anti tamper solenoid, thus they are anti tamper

If your car has the non anti tamper loom then either fit the stop solenoid from your old pump or source a new one and fit to your new pump. I assume they are interchangeable I would do some research if I was you.

Just be careful when opening up the pump, don't let any crap get in so clean around the solenoid well before you remove it.

Yes you would be right it would be a very bad anti tamper device if it could just be bypassed lol. I think I will strip down my old pump and take a look at it and see if you can swap over the stop solenoid.