Hi all,
I have at last picked up my Scoob and i must say its lovely. Its an STI 6 type r V-ltd. As i was driving home on the M20 i decided to give the car a bit of welly when all of the sudden at around 5500 rpm the car hesitated together with a sort of clunking/slapping noise (almost like rev limiter kicking in) and the CHECK ENGINE light came on. I must admit i c****d my pants so i didnt take it over 3500 rpm with no more than 0.5 bar boost. I immediatly phoned the dealer and he told there was 95 ron unleaded petrol in the car (approx 1/4 tank). So i stopped and put £15 worth of SUL with 1/2 bottle of NF Octane boost. Car did the same at 5500 rpm. What i did notice was that the speedo was not working during these occurences and the turbo timer which came with the car was not connected. After about 50 - 60 miles the speedo starts to work and the CHECK ENGINE light turns off. Is it a coincidence??
The rest of the drive home was done so calmly not booting it very much.
Have i had a taste of det?? or is it something more sinister??
My guess is that the 95 ron fuel was mixed with the SUL and octane booster upset the engine. What should i do?
Any help is appraciated as im affraid that if i drive it hard i might cause serious damage.
Regards

Gez

Sounds like something is wrong electrically with the car. Fuel will not cause problems like that, especially as the speedo is malfunctioning.

95 ron fuel in that car guarantees det and that is what you had, thankfully the ecu seems to have gone into limp home mode, it also sounds as though it was combined with possibly getting close to the boost cut if you have a boost guage what was it reading?

the dealer coiuld be considered almost negligent in putting 95 in without telling you, there is no excuse for that these days as the problem is very widely known.

It "should" be ok but insist on him checking it over thouroughly and get it in writing that he has and its ok.

Run it on 97 minimum (Optimax if possible) plus booster all the time and you will be ok. If you have to run without booster then use best quality fuel all the time (not supermarket) and don't cane it up the rev range.

cheers

Bob

95 RON is horrendous for a car like that, but just another thought to throw in:

"What i did notice was that the speedo was not working during these occurences"

http://www.ravensblade-impreza.com/m...agnosisegi.pdf

You or your dealer need to see what diagnostic code has been stored in the ECU as per above or similar. Can't remember if the above covers your vehicle but a lot of the principles are the same if not.

Could there be a speed sensor or wiring fault? - strange that it triggers at 5500 RPM though. Whatever you need the good octane you are now putting in as well.

If that car had 95 RON in it while it sat at the dealers, imagine what the motor has gone through from other test drives. Get it checked thoroughly, firstly at the dealer and then get a second oppinion somewhere else at a tuner shop like BR Developments or PE or Powerstation, etc that knows how and what to check for.

Cheers,

Wrexy.

Forgive my igonorance then, how would the fuel cause the speedo to stop working? While it does sound like det. why did this bring the CEL on ? Is it normal for it to do that? If the CEL came on, surely it would go into 'safe' mode, and reduce the boost pressre so that det. could not happen?

The symptoms you've described (CEL + 5000rpm buckling + dead speedo) are signs of speed sensor defect. This is exactly what happened to my ver 4 Japan spec WRX wagon, the old sensor had to be hacked off the gearbox as it was typically over torqued at the factory. The problem persists and will only get worse until you get the sensor replaced.

http://upload.turbosport.co.uk/getpi...5512228115.jpg

[Edited by Jan Shim - 6/16/2002 2:17:16 PM]

Thanks for the replies guys! The speedo is working fine now but i will have it checked anyway. I have used up all the 95 ron fuel and filled it up with optimax + NF octane boost. Will wait till i have used a couple of tankfulls before i give it any real welly. For peace of mind i will replace the ecu to either Apexi Power FC, Link or GEMS at some stage very soon.

Early scoob's have a sensor in the speedo which sends info to the ECU . When I bought my car (94 WRX ) 2 years ago the speedo had become disconnected during the fitting of the car alarm. On driving the car home for the first time the CEL came on after half a mile and the car would refuse to tolerate any reasonable level of boost as speed started to build up. I'm no expert but my own experience would be to find out if later scoob's ecu's are taking info from the speedo and if so to get the speedo drive / sensors checked out .

Regards,
John

hi i had the same problem with my uk my00 the speedo stopped working the check engine light came on and the car went like a kangeroo over 4500 rpm the problem a loose conection on the speed sensor
another thought as you have a jap import have you had the mph conversion done on the speedo if it has then maybe it hasn`t been done properly

The car seems to be ok now! I think it was just a loose connection but im a bit unsure on how accurate the speedo is. Is there a product on the market which is 100% accurate???

i think the GPS systems are as near as damn it, expect to pay a premium though!!

Gez just as a quick test while not follow a mate and tell him to acelerate and stop at various speeds 20,30,40,50,60,70 and flash him to carry on to the next speed to see how close your speedo is to his.