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Author Topic: Injection Quantity Setting help!  (Read 2894 times)

December 16, 2014, 05:39:00 pm


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Injection Quantity Setting help!
« on: December 16, 2014, 05:39:00 pm »
Hey guys, I have an MK4 TDi jetta. I recently replaced the injection pump seals after they started leaking. I used Vag-Com to tune in my IQ (Injection quantity) to around 3.2. I thought I read that it should be set between 3 to 4.5. But my question is, I had replaced the stock nozzles for my injectors with Bosio DCL PP520 nozzles about 40K miles ago and wasn't sure if I needed to adjust my IQ for the larger nozzles? Now that i have Vag-Com and can adjust the IQ, should I leave the IQ where I have it? or should I adjust it higher or lower with the slightly larger nozzles ??? I'm a noobie to vag-com and IQ info, so I don't know if I should even bother adjusting it from where I currently have it. Thanks

Reply #1December 18, 2014, 09:37:54 am


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Re: Injection Quantity Setting help!
« Reply #1 on: December 18, 2014, 09:37:54 am »
I think once you put in new nozzles you sometimes need to adjust the IQ if it goes out of range. If it's running well and you like the power I'd leave it alone.

Reply #2September 07, 2015, 01:40:20 pm


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Re: Injection Quantity Setting help!
« Reply #2 on: September 07, 2015, 01:40:20 pm »
Just as Tyler said, adjust it manually or vagcom, to where you like it.
There are limits, but you would quickly figure that out. I upgraded to the race520 and it was recommended to adjust to a more conservative IQ, but I preferred it down at 2.7, just feels torque-er and I like the smoke.

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