What happens post new injector nozzle install but BEFORE vag-com tune?

Addamsonflint

Well-known member
Joined
Apr 11, 2012
Location
Columbus OH
TDI
1999.5 Jetta
Hey everyone,

I am looking at putting in some new Bosio injector nozzles soon. I am going to do the install myself, but don't have access to vag-com, so I was gonna do the install, and go see my mechanic (whose a TDI specialist) for the vag-com tuning afterward.


My first question is:

Should I get the Power Plus 520's, 502's, or the 764's?

They are all the same price on IDparts right now. It says the 502's simply "flow more fule" than the 520's, so if I wanted to generate the best power, I wouldn't see why one should go with the 520's.

And I am going to be doing this in conjunction with a new FMIC setup and upgraded intake, which it says is the optimal setting for utilizing the 764's.


My second question is:

If I can't get up to see my dude for a week or two (his shop is kinda far), are there any issues with driving around on the new nozzles without the vag-com tune?

Will I have more smoke?

Will I have more power even before tuned up with vag-com?

Are there any other issues with my engine that I need to be concerned with?

Any help is appreciated.

Thanks!
 
Last edited:

Ed's TDI

Top Post Dawg
Joined
Jan 30, 2001
Location
Victoria, BC, Canada
TDI
2001 Bora and 2016 Touareg
First of all, there's not much that can be done with Vag-com in regard to tuning your car. You'd need to get a proper software tune from any of the major players in the tuning business Like Malone Tuning, TD Tuning, Rocketchip, Unitronic, etc. They will be able to change your ECU's configuration to adjust for the extra fuel you'll be getting with the bigger injector nozzles, as well as add more boost (limited by the stock turbo).

As for your car running with bigger injector nozzles without having any software upgrades will cause your car to smoke more as your ECU doesn't know how much fuel is flowing through the nozzles, only how long the injection "window" is based on its fuelling maps. You will notice more power but also more smoke.
 

Addamsonflint

Well-known member
Joined
Apr 11, 2012
Location
Columbus OH
TDI
1999.5 Jetta
First of all, there's not much that can be done with Vag-com in regard to tuning your car. You'd need to get a proper software tune from any of the major players in the tuning business Like Malone Tuning, TD Tuning, Rocketchip, Unitronic, etc. They will be able to change your ECU's configuration to adjust for the extra fuel you'll be getting with the bigger injector nozzles, as well as add more boost (limited by the stock turbo).

As for your car running with bigger injector nozzles without having any software upgrades will cause your car to smoke more as your ECU doesn't know how much fuel is flowing through the nozzles, only how long the injection "window" is based on its fuelling maps. You will notice more power but also more smoke.

I guess I could have used a better term than "tune." From what I read, it was said that should you decide to change injector sizes "you will need vag-com."

Do I not need vag-com then?


I do want to get my TDI chipped as well. But first I need to upgrade my clutch, and another mod or two as well.
 

JERMS

Veteran Member
Joined
Aug 31, 2008
Location
Sac, CA
TDI
2003 Jetta TDI auto *sold*, 2012 Jetta SE 5spd w/convenience&sunroof
You do need vag com, but not for a tune. You'll need vag com to adjust injection quantity (IQ). Basically, what this does is adjust the fueling for the entire fuel map, kind of like adjusting fuel pressure on a fuel injected gas engine. With bigger nozzles you will be dumping more fuel into the cylinders which will cause the engine to smoke, when you adjust the IQ, you'll back off the fueling a bit to decrease the excess smoke. You'll still have more power but you won't leave a black trail everywhere you go.

For your other question on which nozzles to get, it kind of depends on what mods you have. Some nozzles are made for stock hardware, some are made for aftermarket hardware like bigger turbos intercoolers, manifolds etc. If you go too big on the nozzles with stock hardware, you'll smoke too much.
 

duwem

Veteran Member
Joined
Apr 11, 2012
Location
Wi
TDI
2002 Golf GLS TDI 5 Speed
You might want to do some research about having an expert pressure/flow test and balance your injectors as I dont see that on your list of steps.
 

Addamsonflint

Well-known member
Joined
Apr 11, 2012
Location
Columbus OH
TDI
1999.5 Jetta
You do need vag com, but not for a tune. You'll need vag com to adjust injection quantity (IQ). Basically, what this does is adjust the fueling for the entire fuel map, kind of like adjusting fuel pressure on a fuel injected gas engine. With bigger nozzles you will be dumping more fuel into the cylinders which will cause the engine to smoke, when you adjust the IQ, you'll back off the fueling a bit to decrease the excess smoke. You'll still have more power but you won't leave a black trail everywhere you go.

For your other question on which nozzles to get, it kind of depends on what mods you have. Some nozzles are made for stock hardware, some are made for aftermarket hardware like bigger turbos intercoolers, manifolds etc. If you go too big on the nozzles with stock hardware, you'll smoke too much.
Thanks for the explanation on that- while I'm a decent mechanic and familiar with most aspects of my TDI after working on it the last 2 years, I am still fairly novice when it comes to all the aspects involved in our engines, and don't know much about diesel adjustment and vag-com.

I guess I'm trying to base my decision for injector nozzles, based on what mods I am implementing now, and the few others I will be doing in the very near future.

I swapped out my half-shafts for VR6's while doing my R32 brake upgrade, to better accomodate for the increased power. I'm currently fabbing up my FMIC setup, in concert with a better intake.

I will be upgrading my clutch shortly. I wanted to do it myself, but it is a hefty amount of work, so I'm probably just gonna have my TDI specialist do it- although it won't be cheap, I know it will be done right and w/o problems. I will be either upgrading or simply replacing my turbo in the near future.

I will probably wait on a custom chip, until I have both of those two items complete.

That all being said- any thoughts on which way to go, based on my current setup, where my intercooler and intake will be very shortly, and the other mods in the fairly near future?

http://www.idparts.com/catalog/product_info.php?products_id=500

http://www.idparts.com/catalog/product_info.php?products_id=879

http://www.idparts.com/catalog/product_info.php?products_id=771
 

JERMS

Veteran Member
Joined
Aug 31, 2008
Location
Sac, CA
TDI
2003 Jetta TDI auto *sold*, 2012 Jetta SE 5spd w/convenience&sunroof
Out of those 3, I'd probably go with the pp520, the others might be too big for use with a stock turbo.
 

loudspl

Veteran Member
Joined
Apr 22, 2005
Location
Osakis, Minnesota
TDI
02 ASV w/ 02J
I think you should go with the .216um version of these ;)

If you are only considering Bosio, go for the PP764 and a reduced fuel map

Not sure who your mechanic is, but I would strongly recommend Jon Hamilton in Marysville....he's close to you and worked on my car several times :)
 
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