Running like crap
 

Hey guys and gals,

Got a few problems with the car that i need help dianosing, hopefully easy to do so but if not im booked in to subaru.

At times its like its dead though, like drives fine then ill boost high and then putting my foot down it feels as if the turbo is bunny hopping because it will only go to like 2 psi so i pull over to inspect... Car is idling at 200 rpm boost gauge is sitting at 8 vaccum so i turn car off, sit for 5 turn back on and wammo, its perfect again

I went to MMS and he turned car on and drove soon as he got back he aaid AFM which has since been replaced and is still bunny hopping mid drive when i hit 4500 RPM.

I have no idea but my speedo now isnt workibg and ive been told that could be the problem.... Ill be buying a new speedo sensor and harness for it on monday and changing that myself but if that doesnt fix it then i dont know what to do

An intermittent problem where it is going down to wastegate pressure (~8psi) could most likely be a leak in your vacuum lines. Check the connections of all your vacuum lines and inspect for small slits/cracks/pinholes.

Have already done so and there all fine...

Ut boosts to 16psi before 4500 rpm but as soon as it hits 4500 rpm it happens, dont think its a boost problm

Your hitting the boost cut!

Are you running the stock ecu?

And a boost controller?

ecu has crapped its self? mate of mine had it happen to him was just running weird and ruff and he put a different one in and it solved all his problems

Well how much would a computer cost for my car? And did he just replace with another stock one?

And rossco what do you mean by the boost cut?

I read once that boost cut is at 16psi!, you may just need to lower your boost or get a tune.

Boost cut to my understanding is when the ECU cuts the boost to protect the engine although ive never researched it

Ohk then... I know where my boost controller is, is it just like a tap? Clockwise to shut anti-clockwise to open?

id say because the speed sensor isnt working the ecu cant decide on vehicle speed and hence doesnt know how much air should be flowing over the intercooler so it cant provide stable boost. also changing the speed sensor is a gearbox apart job too.

Best google your particular model and check the instructions?

Sounds like you're going to need a tune in the end anyway.