How to confuse your factory ECU at the wrong time.

[spoonman]

The other night i took my car for a drive after installing the hks hi power cat back and decat pipe, the only other power mod is a intake filter.
After going along at 190 or just in front of the factory speed cut, i thought i would cool the engine down a bit as i coasted down in speed by putting the clutch in.

Nearly crapped myself as the rev counter went to 0rpm and and all engine warning lights came on.

Im guessing the narrow band O2 sensor went off the chart with little exhaust restriction and the factory ECU didn't know what to do other then tell me my engine was not running even though it was. lifted the clutch and it all went back to normal.

Has this or anything like it happened to anyone else?

 

[AllanOrr]

? is yours a JDM Spec R I take it yea?

Never heard of it just cutting out, the speed limmiter from japan just means the engine wont let you go over 120mph sort of like a rev limmiter when your not moving so you dont reck the engine though on my Spec R I got a fresh import roughly the same mods as you at the time and have had it over 140mph...on a track....:wack: lol

 

[craig8585]

Have you got a speedo converter Allan? If so that will shift the limiter to 180 MPH instead of KPH..

 

[AllanOrr]

yea that would make sence though on the evo7 we had which was a import that had a speedo converter done and it was still going into limp mode at 120mph? HKS delimiter lol

 

[Hypnotik]

Are you sure the car didn't die and when you let the clutch back out it started again? That has happened to me before.

 

[JameS15]

Sounds more like the MAF stalling the engine to be honest. Pretty common i think. Youll probably find if youre at idle and rev the engine up to around 6k then let the revs fall it drops lower than idle then picks up again or stalls? Mine does this but i have an HKS FCON to be mapped which does away with the MAF and uses a MAP sensor anyway. Wouldnt think it was anything caused by youre modifications or the speed limiter mate

 

[andeep]

My old S15 used to do this. If the revs are high and you suddenly put the clutch in, the revs drop too low and ended up stalling the engine. I raised the idle a bit and it solved it.

 

[RyanH]

It's usually a dirty idle control valve that'll cause the car to cut out from high revs if you drop the clutch.

To me, it sounds like the car cut out but the ignition was still on, when you brought the clutch up, it just bump started the car again.

 

[spoonman]

that's the thing that surprised me the engine didn't stall as far as i could tell....... otherwise when lifting the clutch i would have felt the it start again like trying to roll start your car but only at about 170kph and pulling the revs to 4000 would have been rather harsh you would fell that wouldn't ya? on it or have i got that wrong??, but it was smooth as i didn't feel a thing, i didn't move the key at all it was still set to ON

 

[Jay]

at that speed you wouldnt notice the engine roll starting. you may have an aftermarket clutch installed without your knowledge that involves changing the dual mass fly. with a lightened fly, it struggles sometimes to hold the revs and can stall. mine does it from time to time, but i have more mods

 

[crazymat666]

yeah does sound like you just bumped it to be honest,but mine after a high rev if its at idle jst revving pointlessly or actually going along and i come to a sudden stop or put the clutch down it does drop right down it doesnt stall but drops.but mine is due to a few mods thats all