My DC5 keeps bogging around 5000rph

[C&S Evo7]

they need to use the correct wideband lambda probe not some rubbish from europarts etc. a civic one is not the same.

id check the filter on the pump in the tank, its not too difficult to get at and ive known them to come off and get clogged with stuff , although i dont really see why a full tank would be any different to 1/4

 

[leejw87]

Ok update here so I decided to fill the tank with fuel and the car performs amazing hits every note
So thinking of replacing the fuel pressure valve and the fuel filter
What do you think ???

By the sounds of things the fuel filter gauze could be partially blocked and by filling it to max the weight of the fuel could be helping push through any restrictions, I'd be checking your pump gauze for any blockages.