gazskooby2006

Ok I have an Impreza wagon MY94 uk turbo running a Magnex centre decat and backbox also a polar performance chip fitted. I took my car for cambelt change and whilst i was at scoobyclinic i had it rolling roaded it should be putting out 270+bhp but it did 227.9 now i have spoken to scott t who does the chip who is very helpful but like myself he is confused as its hitting target boost, AFR is spot on there is no misfiring or detting and no faults on the ecu, has anybody got any idea what could be causing this problem all i get told at scoobyclinic is we can tell you but it will cost 42 quid an hour to find out any ideas will be appreciated.

David_Harden

Apologies for asking an obvious question, but the power you were given by Scoobyclinic was at the flywheel was it? If it was 227.9 at the wheels, that would be about right for 270bhp at the flywheel!

Scott.T@PolarPerformance

We've been round most things, but you mentioned you fitted a Magnex rear box at the same time.
It would be worthwhile having a look at this by shining a torch up it to make sure there isn't any foreign objects, misalignment or any baffle material partially blocking it.

If you have a Centre CAT, it could be that this has colapsed and also possibley partially blocking the system.

It does sound that somewhere on the car there is some sort of restriction going on.
Even a car with just a Dawes Valve or Boost Controller would achieve more then 227BHP if it were able to run 16psi.

gazskooby2006

the figure is at the flywheel, I have no centre cat. I have noticed that the headers are a bit rattly could it be them leaking or the up pipe??

Scott.T@PolarPerformance

what headers are they, standard, quality aftermarket or cheap aftermarket ????

If their aftermarket and really poor quality then the bores or the bends could be a restriction.

Leaking will slow down the spool, but you are achieving 16psi, so probably not the problem.

gazskooby2006

oh ok they are standard headers, the only other things the car does is the exhaust pops and i get the odd smell of petrol from time to time but can see no fuel leaks i will check the exhaust over the weekend, it does seem bizarre as your right it is hitting 16psi yet still no power

gazskooby2006

one other thing it does is if you pull off in 1st hard it hesitates for a second before getting going could it be a fueling problem maybe??

Scott.T

iTrader: (2)

fueling was fine on the RR plot.
Rich but as expect, as they do run rich both standard an postal mapped. Plus a rolling road will alway show richer on the rollers then it is on the road.
I only start running AFR in the 11's on a custom map.

gazskooby2006

sorry i meant a fueling problem as in fuel leak/pump etc

scoobynewbie72

iTrader: (1)

Has the car lost power when u drive it, ie have you noticed it has lossed power or was it just on the rolling road that you realised it wasnt right ?
Also try another Rolling road maybe it was a hot day when u were there or there was a little wheel spin or u had a bad batch of fuel.
If your hitting the correct boost though and it shows as fueling ok id just try another rolling road see if it was just a blip on that day.

robsw

Me and a few other chaps on here have had this same problem in first gear. Apparently someone who had this problem cured it by changing the std fpr (fuel pressure regulator) for an aftermarket one. I havn't tried a replacement fpr on mine yet but will be when the bank account agrees.

skywalker23

The hesitation ur getting could be Maf sensor problems....

gazskooby2006

i thought maf problem but i get no error codes on my ecu to suggest its wrong, i had noticed a performance drop and they advised rolling road as the best way to identify problems. apart from odd smell of unburnt fuel from time to time and the popping exhaust the only other thing i have is if i reset the ecu i get code 43 and it puts me into limp mode down to about 0.4 bar and i have to unplug the battery for half hour then its fine again, I think its gonna be the 42 quid an hour at scoobyclinic to sort the problem out

Scott.T@PolarPerformance

Why not go to Zen as I suggested.
I've already given Paul a heads up on the situation.
Infact I've even PM'd Scoobyclinic on your behalf on the subject (although not had a reply).

Don't let them throw the chip in the bin and charge you £380 for a remap until they have checked it on the rollers running the standard ECU map.

Code 43 is a red herring on a UK as it's using Z4 ECU running code. The Z4 equipped car has a TPS Diagnostic check that the UK car doesn't have.
Even a UK car running the Prodrive ECU logs it.....because.....it uses Z4 ECU code.