Ek4 trouble

[Ek4gav]

Hi I'm new here I'm hoping someone can help me out I have an ek4 and she's not to well. There is a hesitation at low acceleration. I have changed fuel filter,throttle position sensor,map sensor,dizzy and rotar and plugs the problem is still there anyone have any idea of what it could be? It only happens below 3k rpm and is fine above that

 

[Ek4gav]

I've also ran diagnostic checks and nothing showing up and also reset ecu

 

[XpL0d3r]

I had a similar issue to this, and it ended up being my primary o2 sensor. It was taking readings, so it never threw a code, but the readings were not correct, so it messed up my A/F ratio.

For the issues you're having.. does the car work fine when the engine is cold, but has issues once it warms up? If so, the o2 sensor would be my first guess. Car runs open loop when it's cold, so it's not taking any feedback based off the sensor. But once it warms up, it switches to closed loop and will adjust your A/F ratio based on the readings the ECU gets from the sensor. If the readings are whack, the A/F ratio probably will be as well.

 

[Ek4gav]

I does it both warm and cold is that the 02 sensor in the exhaust manifold I changed it about 7 years ago as I've had the car near 10 years lol love it too much to get rid of it

 

[EK4joe]

10 years is good going for an 02 sensor I'd change it, you checked for vacuum leaks, exhaust leaks ?
Also what induction kit are you running ? I run a j's racing whale cock rep and suffer a from heat soak.

 

[Ek4gav]

No exhaust leaks as far as I'm aware of. Running standard airbox with his panel filter. Can't hear any leaks. My mate has an o2 sensor so going to try that thanks for all the help

 

[Ek4gav]

I drove the car from work to home cold and there where no issues