Just happened coming home. Mechanically everything seems fine and off boost car runs ok. Im guessing its a sensor gone, but any ideas which one? It seems related to engine acceleration or rate of increase of boost as the car will run for a while in top gear on max boost (0.8-0.9 bar), but will cut out (violently) as soon as the boost climbs in the first three gears.

The car wont rev in neutral past 3k without cutting out, but again runs fine off boost and under load.



Over to you experts........

Thanks in advance!

Andy

Edited to say its a 93 WRX with a PE ECU.

[Edited by kwakman - 12/17/2002 1:43:07 PM]

 

Sounds like it's in limp home mode. Not sure what you should look for. I'm sure somebody else will be able to give you pointers

 

I think Ive been in limp mode and it seemed to restrict the boost to 0.5 bar with no sudden cut out. This is much more violent and the turbo does boost to its max b4 cutting out.

 

Mine did this sort of thing on the way back from le mans soon after I got it. It gave me the *******. Overtaking a car up a hill it decided to suddenly cut all boost and the engine check light came on. Engine sounded fine so I trundled along for a bit and it went out. Seemed ok after that.

The explanation seemed to be that due to my dodgy speedo converter that sometimes did not come on until several miles into a journey the ecu was not getting a speed signal and decided to suddenly enter limp home mode - perhaps after seeing a certain boost level too. After the speedo came on it decided all was well and acted normally.

Best option is to get it to a garage or someone with deltadash or a fault code reader and see what faults are logged.

 

Eric I think youve nailed it. Ive got a speedo converter that has just gone wobbly, but Id assumed that would make no difference. Is the road speed signal taken from the dash then????

Ooooo-errrrrrrr.

Will replace speedo converter and keep fingers crossed.

Cheers

 

coilpacks, it's the coilpacks.

had exactly same problem with my old 93wrx. engine cut when on high boost wouldn't get past 4k rpm without breaking my neck jerks.

check engine light came on, had different error codes.
changed lambda sensor, the whole pressure sensor, solenoid, fuel and map sensor to no avail.

then was asked to change coilpacks and problem solved.

 

Was speedo converter. Going like a goodun again. Thanks for ur help peeps.

Andy.

 

Nice one. Glad to help.

I guess the speedo itself does provide the signal to the ecu. I'm pretty sure I read somewhere on here that the ecu doesn't actually use the speed signal it gets mapping wise but it sure as hell has a fit when you keep driving along for a while without it.