jbm_a4b5

Good day guys new member here hope to learn a lot from you about audi a4 from you guys. Just bought my first audi a4 1997 1.8T manual transmission. I wanna try the brand.

My concerns are:

1. When the car is running in neutral my idle is wild up and down like 400 to 900 but when in a full stop still in neutral the idle will be fine stays at 600. What is the problem?

2. Always hard starting need to step on the gas few times before start. Changed the fuel filter still no improvement.

3. When my rpm hits 5,000 above in 2nd and 3rd gear my idle goes rough like lost in power.

4. Lastly newbie question. At what rpm the turbo kicks in?

Thank you very much!

twentysevenlitres

Ok, firstly, why would you put the transmission in neutral while the car is in motion?
The ECU is programmed to cut ALL fuel use when rolling off throttle in gear (ie, when rolling down hill in gear, the car uses NO fuel).
Putting it in neutral forces the engine to idle (which uses fuel). The engine is probably reacting to the speed sensor. So leave it in gear!

Hard start can be difficult to diagnose, but is likely fuel related.
Could be blocked fuel filter, bad pressure regulator, injector leak-down (dirty or worn injectors), or bad non-return valve or failing fuel pump (both require pump replacement).
It could even be caused by things like the crank angle sensor and temp sensor.

DO NOT pump the throttle/accelerator when starting a fuel injected car!
You risk back fire, and it doesn't aid the ECU in starting the car.

Loss in power could be a number of things.
Sounds like you have a problem or two. You need to have the car scanned with VCDS/VAGCOM, which will give error codes to point you in the right direction.
You can either buy your own cable and download the software from Ross-Tech, or find a local VW/Audi specialist (or if you're feeling brave, go do a dealership!).

jbm_a4b5

Thanks for the reply bro! My other cars when in motion in neutral gear the idle is stable. So what you mean is that our audi is different? I do not cruiser down in neutral that is dangerous. What i meant was even for just 20 meters in motuon the idle goes up and down.

twentysevenlitres

The fluctuating idle is probably symptomatic of other issues.
I would expect a smooth idle when rolling in neutral.

jbm_a4b5

Good news i already solved my idle problems! I checked all the check valves i found out that one was in the reverse position so one of the hoses was blocked no air was entering! Even my hard starting got better by 50%.