For Your Info - Dual Spring Injectors

There seems to be some information floating around that gives the impression that setting the 2nd spring of dual spring injectors (such as used on VW TDI) is not really required. We have seen DIY documents that provide step by step instructions for installing new nozzles into your TDI without any regard for the nozzle settings. Even Robert Bosch the OEM supplier of TDI injectors is selling a nozzle kit that they claim can be installed into an injector without the need to worry about the 2nd spring setting procedure. This really puzzles us! There are simply too many variances and wear issues in the nozzle holder for this type of procedure to be successful with any consistency!

We are not sure why this is being done, other than the fact that very few places have the equipment and/or parts required to do this procedure properly. We disagree with these claims, and have had many cases where we can support our position. The following email that we received from a customer in Massachusetts, USA says it all, and it is being used with his permission. This customer had done what seemed to be the norm ... he purchased new nozzles and installed them into his own injectors. This is what he tells us ...

Just a note to let you know that the rebuild work that you did on the injectors for my 2001 VW TDI has solved the poor fuel economy problem that I was having. At 165,000 miles the fuel economy had dropped from 50 down to 40 mpg over a six week period. I installed new nozzles (OEM spec) myself in an attempt to solve this problem but the fuel economy remained at 40 mpg. After testing several engine parameters like compression, valve timing, and injection timing and finding them to be OK I decided to send the injectors to you. Your rebuild and balancing using the same nozzles has restored the fuel economy to 50 mpg. The engine is also significantly smoother, like when it was new. Thanks for the service and I will know where to send the injectors when they next need attention.

R.S.

This email speaks for itself. We have made a significant investment in equipment to set and flow dual spring injectors, and this enables us to again provide a product that works as when it was new. Why settle for anything less?