Hi haveing boost probs with sti type r v3 import when cold boosts but not that much when hot it feels like it as no turbo checked the ecu codes ok and reset ecu i have owned the car 4 6 weeks and it is runing esso 97 fuel.Could the fuel i am using be the prob because the guy i bought the car of ran it on optamax.

 

It won't be the fuel ron.

How sure are you that its gettin some boost when cold?

 

it pulls beter when cold and u can feel the turbo come in but feels like some times its holding back.

 

you should run it on optimax as it is an import and japanese fuel is a lot higher octane. the closer to i think 102 the better as that is what the ecu is programed to. i think its v power now not optimax which if correct me if im wrong is 99 ron

 

I read this and found it very usefull re: fuels etc...
Check out 2.4.1

http://www.sidc.co.uk/faq.htm#2.4

 

so if i go back 2 optamax and reset ecu all should be fine or do u think it could be something else. And the reason i use esso 97 is it is locel and optamax is miles away

 

HI just come from work and car was boosting but not as it should but beter than yesterday have u any ideias have not toutched enything it seems to get beter then go all to pot.

 

This is a total shot in the dark..... but if it is boosting ok when cold and then not too well when hot, could it be a lambda problem?

IIRC - the lambda only starts working when up to temp, before then the ECU does the job.

Like I say - total shot in the dark, and I may be wrong about the Lambda/ECU thing.

Have you reset the ECU to see if any codes are being thrown up?

 

Sorry - just re-read your post where it says that you have tried resetting the ECU

 

thanks mate but i have tried ecu check and ecu reset just orded plugs fuel filter and air filter.

 

Lambda will not affect boost, yes only used when hot but that is about 20 secs after start, lambda is only used for closed loop control (idle and light cruise) Fuel, plugs, fliter etc i doubt would cause a dramatic loss of boost, do you have a boost gauge? I know it sounds strange (it was said to me and i thought the same) but you could just be getting used to the car, i fitted a gauge confirmed this!!

Worst case it could be a turbo siezing when hot, my stab in the dark!!