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Discussion Starter · #1 ·
I had a strange problem yesterday. I seem to remember someone else having the problem, but I don't remember exactly, and their problem may have been that the engine was cold.

After restarting the car after it was parked for about an hour, my car acted normal. As I drove it fully warmed up. Then when pulling away from a light, I hit 6,000 RPM. The shift light came on, and the rev-limiter kicked in. I wasn't pushing it, but it took me totally by surprise. I tried to get it above 6,000 a couple more times, and each time the rev-limiter kicked in, and yes, the engine was at normal operating temperatures.

A parked the car and came back to it three hours later. It started and drove fine. After it warmed up, it reved past 6,000 without problems.

Anyone else have this problem? The car was fully warm, so it was not a cold engine limit. :shrug:
 

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I suspect there are a number of inputs to the ECU that affect the rev limiter besides temperature. Or perhaps a reading was off and had to be reset by turning the car off and on again? Whenever something electronically weird happens in my car (usually the TT) I restart it and it almost always just goes away.
 

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I had this happen a while ago where the car was most certainly warmed up (had been driving about 25 miles) and the car had already redlined while climbing through the gears. Then I slowed down for some local streets and then went back onto the highway. When I stepped on the gas, I noticed what felt like an undulating sensation as if the pavement was wavy. But I only noticed this on acceleration and thought that it was linked to some weird power delivery. Then I went to merge onto another highway and stepped on it....same pulsations and then an early rev limiter kicked in. WTF!?!? I then shut the car off and restarted while coasting on the freeway :evil: and the problem went away completely. Very strange.
 

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ekological said:
I had this happen a while ago where the car was most certainly warmed up (had been driving about 25 miles) and the car had already redlined while climbing through the gears. Then I slowed down for some local streets and then went back onto the highway. When I stepped on the gas, I noticed what felt like an undulating sensation as if the pavement was wavy. But I only noticed this on acceleration and thought that it was linked to some weird power delivery. Then I went to merge onto another highway and stepped on it....same pulsations and then an early rev limiter kicked in. WTF!?!? I then shut the car off and restarted while coasting on the freeway :evil: and the problem went away completely. Very strange.
I have had this "pulsing" sensation too, right after starting up with an already warm engine. It went away pretty quickly, and I haven't had it happen in a few months. Must be some ECU weirdness.
 

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I have noticed intermitent "surging" under 3/4 throttle accelleration. has happened a few times where its pulling, but feels like a car with super fouled plugs or something where its only firing 80% or something. mysteriously goes away and no rhyme or reason to the few times i have noticed it. But i haven't had the 6k rev limit issue ?, and i typically try to make it a point to get up three at least once or twice every time i drive it :)
 

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Tim if you plug it into the lotus computer you may find it has had a misfire and temporarily dropped into a fail safe mode. This is usually caused by emissions concerns sensed in the exhaust. It the resets on restart if the problem does not continue to be detected.

Alternatively you have the touring ECU activated.
 

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Discussion Starter · #9 ·
drac said:
Alternatively you have the touring ECU activated.
:thwack: What? I hadn't thwacked you before?rotfl

For what it's worth, it's been almost a year, and it's never happened again.:shrug:
 

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sadly... i'm dealing with the 6k rev limit issues right now with my elise. i just read something about the exhaust emissions... and wondering if putting the larini on or the arqray straight pipe is setting something off... :huh:
 

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I had it happen on a dyno run. There was nothing else to do but see if it repeated. Subsequent runs were fine. I doubt if there was any detonation causing it, I had a little unleaded 100 octane aded for that reason. I have to wonder if it's a coincidence but it occurred right at the cam shift point.
 

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turning it off; turning it on............ = ctrl, alt, del ! resets the computer ? Anytime we have electronical ( ! ) problems with the airplane, we do the same thing.... usually cures it.
 

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Discussion Starter · #13 ·
MikeW I have to wonder if it's a coincidence but it occurred right at the cam shift point.[/quote said:
Not necessarily the cam shift point - the system also limits the RPMs to below the cam shift point when the engine is cold, or when it detects a malfunction. I doubt that it has anything to do with the cams shifting, it's just that that is the "Fail Safe" RPM that the ECU limits things to...
 

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TimMullen said:
Not necessarily the cam shift point - the system also limits the RPMs to below the cam shift point when the engine is cold, or when it detects a malfunction. I doubt that it has anything to do with the cams shifting, it's just that that is the "Fail Safe" RPM that the ECU limits things to...
yes, but I was referring to mine. It wasn't cold. The fact that it picked the rpm where the cam shift kicks in is peculiar. Maybe something went haywire at the 6200 rpm point or didn't shift properly and the ecu sensed something bad and made a pop. The dyno guy let off as he didn't want to be responsible for anything.
 

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The failsafe is just before the cam transition, mainly because bad things happen when it transitions and theres no oil so for safety it keeps it out of that range < 6200.

i've seen a couple of similar things happen on the dyno around the switch.

I forget what its called but theres some sort of special oil (or additive) that can be added to the engine to help with problems with the lifter mechanism, that helped on one car.

a pop usually means fuel dump.

if the ecu gets unhappy it can flip flop on the limp home, which becomes the rev limiter at around 6000 + red light, fuel dump and then its fine again.
 

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Discussion Starter · #16 ·
MikeW said:
yes, but I was referring to mine. It wasn't cold. The fact that it picked the rpm where the cam shift kicks in is peculiar.
That was the point I started this thread with - it happened to my car. It was fully warmed up, and the rev limiter (and light) kicked in at the same point that it does when it's cold. It's also happened to several others. In my case, it only happened one time, and never again...:shrug:
 

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Happened to me today for the first time. Turning the car off and restarting solved the problem. Caught me very much by surprise.

Mike
 

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Add another instance of this weird problem happening. Today on my way home it happened. Engine fully warmed up. Shift light came on early at 6k rpm and then fuel cut-off. Happened several times in various gears. Shutting off the engine and restarting it seemed to cure the issue. :shrug: :tadts:

2005 model, 7.5k miles. Stock intake and exhaust.
 

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Mine did this to me as well but only in 1st gear... perhaps the speed sensor had something to do with it?

It would rev all the way to redline in any gear but first. Was very strange... I shut it off and it continued to do it until I let it sit overnight. It was fine the next morning... :shrug:
 
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