TDI Injector Swap and ECU Tweak (Vag Com)

GTE

Hello!

The car is a 1.9 TDI with the AGR engine code. 90hp.

I can get a set of 110hp injectors for the engine in the next week. I have a few questions.

Firstly, if my engine still produced 90hp, would the 110 injectors give me 110hp? Somehow in my ignorance I doubt it without changing the turbo.

I have been advised by two re-mappers/engine tuners not to get my engine remapped due to the turbos age (12 years old, 180 000 miles), it could not take it.

This is the first time I have really thought about getting the injectors changed as opposed to a remap.

Will the turbo be overstressed or given more load as I am actually changing a component to give me more power rather then an ECU map change?

I also read up that I would need to get a fuel injection setting changed to suit the new injectors but I have also read that you can leave it as it is and change if you dont want so much smoke (general internet how to and myturbodiesel.com respectively). Can this change be done using the free Vagcom with a third party cable or would I have to find someone (and possibly chug around the place smoking it up ).

The person who has the injectors is going to fit them (for 100 euro incl. injectors) but not do any ECU changes, which I am disappointed about.

Thanks for reading. I am getting loads of car stuff done this week when I should be doing college work

Chimaera

The 110 bhp TDI has slightly larger injector nozzles than the 90. But it also has a larger fuel pump and turbo to make the extra power. Expect probably about 10 bhp increase max. It won't put any extra stress on the turbo. Also, unless the injector nozzles are brand new and the injectors themselves have been reconditioned, I wouldn't bother doing this: the gains are going to be marginal.

The ECU setting that can be changed is the injected quantity (IQ). This really just changes the way the fuel pump responds to requests for fuel. With such a small change on the injectors, this change is probably not needed.

For a remap, you're advised to make sure your car is in good condition mechanically. At 180000 miles the turbo is not going to be at its best: whether it's up to a remap depends a lot on the maintenance history of the car. If it's had the correct oil used at the correct service intervals, it could be fine, but the tuner may not want to take the risk on it.

I would think the best nozzle to get is probably the Bosch DSLA 150P 520. This will get you around 10-15 bhp extra over stock without being too smoky. A remap on these nozzles could bring you up towards 135 bhp but you'd need your turbo in good order for that.

FWIW my car is running Fratelli Bosio Powerplus 520 nozzles bought in early 2007. I got them tested by an injection specialist last year who reckoned they're in need of replacement soon. They have about 100000 km on them. When I got my car remapped 2 years ago, the before dyno showed 128 bhp at the crank with these nozzles on board. The remap got me to 139 bhp with an increase in torque to 328 Nm and a much wider powerband. This is starting with an AHU TDI 90. Bear in mind VW tend to quote power figures at the wheels rather than at the crank.

Final note: you should inform your insurance company about any mods you make. It ended up costing me no extra to disclose mine.

GTE

Chimaera wrote: »

The 110 bhp TDI has slightly larger injector nozzles than the 90. But it also has a larger fuel pump and turbo to make the extra power. Expect probably about 10 bhp increase max. It won't put any extra stress on the turbo. Also, unless the injector nozzles are brand new and the injectors themselves have been reconditioned, I wouldn't bother doing this: the gains are going to be marginal.

The ECU setting that can be changed is the injected quantity (IQ). This really just changes the way the fuel pump responds to requests for fuel. With such a small change on the injectors, this change is probably not needed.

For a remap, you're advised to make sure your car is in good condition mechanically. At 180000 miles the turbo is not going to be at its best: whether it's up to a remap depends a lot on the maintenance history of the car. If it's had the correct oil used at the correct service intervals, it could be fine, but the tuner may not want to take the risk on it.

I would think the best nozzle to get is probably the Bosch DSLA 150P 520. This will get you around 10-15 bhp extra over stock without being too smoky. A remap on these nozzles could bring you up towards 135 bhp but you'd need your turbo in good order for that.

FWIW my car is running Fratelli Bosio Powerplus 520 nozzles bought in early 2007. I got them tested by an injection specialist last year who reckoned they're in need of replacement soon. They have about 100000 km on them. When I got my car remapped 2 years ago, the before dyno showed 128 bhp at the crank with these nozzles on board. The remap got me to 139 bhp with an increase in torque to 328 Nm and a much wider powerband. This is starting with an AHU TDI 90. Bear in mind VW tend to quote power figures at the wheels rather than at the crank.

Final note: you should inform your insurance company about any mods you make. It ended up costing me no extra to disclose mine.

Great post, thanks.

I take it your AHU90 is a PD TDI?

One thing I'm learning is that the injectors are consumable parts. 100 euro for 10hp more is a lot, though my injectors must be 12 years old so maybe more. Ill think about getting new injectors or recons over summer. I just found a VAG COM guy locally and he was quite helpful.

I'd love some more power, nothing mad. 110 or 115 but there is nothing wrong with the car and I think ill have years left with it if I leave it stock. I am very picky about oil but I've had the car 3 years so previous owners may not have been.

There is that tuning box which I think just fools the engine into throwing loads of fuel in ( the Emry mod?). Doesn't look fun on the engine.

I think with enough confidence and how tos, I could swap injectors myself. Number 3 looks tricky and I need to figure out fuel pump priming I think. For another thread though :-)

Chimaera

The AHU engine is an older version of the AGR engine your Golf has, so it's a VE as well. The AHU is part of the EA827 engine family, and AGR is part of the EA111 family.

Tuning boxes/Evry mod are best avoided. The fool the engine into over-fuelling, but there's nothing to correct the airflow to compensate, so you end you up with lots of smoke and excessive exhaust temperatures.

The injector swap is pretty trivial. I did the nozzle swap on mine in the garage at home, and they've been fine. You just have to make sure to replace the copper crush washers and torque down the securing bolts properly.