problems with cold start and idle on 2.3 NG

Zorkar

Hello, i got the invent up an running and when it is warmed up it runs great.

Problem is with cold starts and idle when engine temp is below 30-40°C. it needs some throttle to start. i am using the 4.1.5 calibration for audi 2.3 where coldstart enrichment is already set to 140. tweaking this +- 20 or 40 does not help.

i also noticed that when setting the idle slider manually, there is only a real change between 25% (lower is icv closed) and around 40-50%. i optically checked that moving the slider really changes the opening in the icv and it does. i feel the icv vibrating when plugged to the invent, but not when plugged to the original connector.

any ideas? how can i figure out if its to rich or to lean while starting?

thank you very much.

Zorkar

I want to add that it is somewhat impossible to raise the idle above 850rpm with the slider.
i did also disconnect everything in front of the icv to rule out that i have something blocking airflow in the piping from airbox to icv

JHM

Zorkar
Normally, you can easily crank up the idle RPM up to 3000 with the manual slider.
I think you should look up here first.

Maybe the idle air path is blocked after the ICV.

Zorkar

I have replaced the cold start enrichment valve with a 3d printed plug.

maybe this is reaching to far inside the channel. i will try removing it and see what is happening.

thanks

Zorkar

i removed the plug and reinstalled the original cold start enrichment valve. also checked if something is stuck in the channel or the piping after the icv. nothing.

tried to start the engine, did not work without throttle.

maybe i messed up the timing when i changed the timing belt. i will check that

Zorkar

Timing belt ist set up correct. Ignition ist at 15°

When i unplug the icv piping from the injection cooling intake it gets better and will start better because it can draw in additional air

JHM

Probably the injector cooling air path is partially blocked.

Zorkar

the white connector has a build in restriction (1,7mm) for the cooling air path, but that is a original audi part that worked flawless before. I have seen that this is left open in the installation manual

should it be left open or be connected with the original restrictor into the idle air path?

JHM

Original ICV air path is separate from the injector cooling path. Your piping is not stock, that's why it is not working.
Removing the restrictor may help.

Zorkar

Thanks for clarifying! But that doesn't apply in my case. Perhaps there are other variants for different countries or engines. I've attached some screenshots to illustrate my situation:

Old version for NG1 in Germany:

Newer version for NG2 in Germany (my case, with the white elbow piece with restrictor (No. 19))

Anyway! To obtain a functioning base map with the 4.1.5 Audi 2.3 calibration, the cooling path of the ICV must be separate, as JHM correctly stated, otherwise the engine will not get enough air. Perhaps it is sufficient if it is unlimited but combined with the ICV air path (not tested).

This could be mentioned in a small paragraph in the installation instructions to avoid this error in the future.

Thank you very much for your support :-)

Kind regards,

JHM

Thank you for clarifying. This version of NG engine should be quite rare. I've never saw it.
I will add this info into the manual.