Brands Hatch Engine Problems
Discussion
Thought I'd throw this one out to you clever lot. During the recent Brands Hatch track day I was getting some mil light engine problems.
Strange thing about the mil light. I was doing some diagnostic runs at the end on brands to work it out. The light came on in the combination of a corner usually left although once or twice right, and a boot full of throttle. If I pushed the throttle in gradually while accelerating I didn't get the problem but still got the same amount of acceleration round the corner. All the time the oil pressure never moved under 60. Because of those two I thought it unlikely to be oil pressure related. If the mil light came on I could switch it off just by reducing the load slightly by matching the throttle to where the engine was. There was no change in acceleration between mil light on and full throttle and foot off the throttle a bit and mil light off. I could then go round corners at whatever speed without the light comming on.
Gives the impression it was complaining about the load/rich fuel amount. Although I didn't realize the mil took any interest above 4000 rpm.
Obviously keeping the mil off changed my driving style on the day, because I had my eye on the dash all afternoon, and wasn't trying to provoke it before I find out why, I didn't want to push it. Adding oil to the sump didn't make a blind bit of difference during the day. Although it seemed to cure Simon in his tuscan, probably for different reasons.
Not had the mil light on before or since on spirited driving. Anyone got any pearls of wisdom to share?
Strange thing about the mil light. I was doing some diagnostic runs at the end on brands to work it out. The light came on in the combination of a corner usually left although once or twice right, and a boot full of throttle. If I pushed the throttle in gradually while accelerating I didn't get the problem but still got the same amount of acceleration round the corner. All the time the oil pressure never moved under 60. Because of those two I thought it unlikely to be oil pressure related. If the mil light came on I could switch it off just by reducing the load slightly by matching the throttle to where the engine was. There was no change in acceleration between mil light on and full throttle and foot off the throttle a bit and mil light off. I could then go round corners at whatever speed without the light comming on.
Gives the impression it was complaining about the load/rich fuel amount. Although I didn't realize the mil took any interest above 4000 rpm.
Obviously keeping the mil off changed my driving style on the day, because I had my eye on the dash all afternoon, and wasn't trying to provoke it before I find out why, I didn't want to push it. Adding oil to the sump didn't make a blind bit of difference during the day. Although it seemed to cure Simon in his tuscan, probably for different reasons.
Not had the mil light on before or since on spirited driving. Anyone got any pearls of wisdom to share?
julian64 said:
Extra 300 Driver said:
Fuel pressure??
Interesting but is that actually logged as a fault?I could also be talking rubish!
If it is fuel you would notice an engine hesitation, but if it is its probably due to there being inefficient or no baffles in the fuel tank, If this is the problem a swirl pot is you answer to keep the fuel on tap. This has happened to John who owns a Sagaris when tracking/sprinting
Just a thought.
Just a thought.
Edited by YI8TVR on Saturday 2nd June 11:19
Edited by YI8TVR on Saturday 2nd June 11:20
After a hard evening at brands, I have now removed my exhaust, rewelded the joint at the back box that blew apart.
Then put the diagnostics on the running engine, and the cause of the problem seems to be Tpot values out of range (well done Mikesr!)
Am very relieved. The throttle pots currently read from 14.4 to 97.4. At foot to the floor they just go over 97.4. The computer keeps the throttle value at 97.4 and records a throttle log fault. Both throttles had logged this fault, which only causes a temporary mil light while its over value.
Obviously mid bend I was sticking the foot to the floor which says something about how well the nitrons were keeping the car planted!! Lifting off slightly, obviously caused them to go quickly back within range.
The diagnostic software showed no sign of an overrev, and temperature values during the racing well within the limits of the fans. Shame it doesn't record the oil pressure in the same way.
Anyway, despite my anxiety, having mil lights on and then the rattly engine on the way home which turned out to be the exhaust hole. Everything is now running sweat as a nut again.
Only problem now is whether to do the emerald wirlwind thing and redesign of my throttle bars before september
Thanks for you help
Then put the diagnostics on the running engine, and the cause of the problem seems to be Tpot values out of range (well done Mikesr!)
Am very relieved. The throttle pots currently read from 14.4 to 97.4. At foot to the floor they just go over 97.4. The computer keeps the throttle value at 97.4 and records a throttle log fault. Both throttles had logged this fault, which only causes a temporary mil light while its over value.
Obviously mid bend I was sticking the foot to the floor which says something about how well the nitrons were keeping the car planted!! Lifting off slightly, obviously caused them to go quickly back within range.
The diagnostic software showed no sign of an overrev, and temperature values during the racing well within the limits of the fans. Shame it doesn't record the oil pressure in the same way.
Anyway, despite my anxiety, having mil lights on and then the rattly engine on the way home which turned out to be the exhaust hole. Everything is now running sweat as a nut again.
Only problem now is whether to do the emerald wirlwind thing and redesign of my throttle bars before september
Thanks for you help
Olly said:
If it's running too lean/rich your adaptives will probably be out (up to 18% is ok - from memory). If it runs too rich/lean for too long though, you should get the ARF fault logged (air/fuel mix)
Whats the right sort of mix? On the rolling road yesterday mine was at about 14% which the operator thought was a little lean. My MOT's next week so I thought I'd leave it until after that.Gassing Station | Cerbera | Top of Page | What's New | My Stuff