111R - loss of power on high lift cam

[otolith]

It's had an intermittent fault recently, whereby it changes onto the high lift cam but won't rev. It seemed to have stopped doing it, but I've just had it reflashed to lower the cam change point and it's doing it again. Fault is not in any way related to the reflash, I don't think. It will now rev all the way out to the shift light, but there's no power.

(Obviously the oil level is correct and the engine is warmed - and it is engaging the high lift cam, you can hear it, it just isn't making any power when it does)

This is it:

http://www.youtube.com/watch?v=ISZrgxqvFCo

Anyone seen this before?

[otolith]

Thanks Frank, unfortunately that was my first dashed hope for an easy fix when it first did it

[otolith]

Thanks Bearings - no, definitely not the cold limiter, engine fully warmed through, oil level fine. I don't think it is a fault with the mechanism, I believe the cam is engaging - there is a very obvious change in sound when it happens. It has also been intermittent, which suggests to me that it isn't anything worn or broken. I hope so anyway.

I did wonder if it was something like the catalyst breaking up, but I'm starting to think a sensor on the fritz is a more likely problem. Going to get it plugged into the diagnostics next week to see if any fault codes are being logged.

[otolith]

Just to illustrate what it's doing - this is from Dynolicious, just pulling away in 2nd gear and accelerating to max revs in one gear. (Ignore the absolute numbers, they're based on what you enter for weight and transmission losses). Yellow line is power.

From when it wasn't playing up:



This is what it is doing now:



Can you see the problem?

(at least the lowered cam change is working though!)

[otolith]

No, clutch is fully engaged, just no power and revs rising very slowly.

I've just taken it for a little drive, and I think it's now down on power everywhere. Didn't try taking it onto the second cam.

Someone has suggested coil pack failure as a possibility - could that be intermittent at first then gradually worsening, I wonder?

[otolith]

No CEL showing, no. I've pulled the coils out - lots of brown residue. After wiping them down, they look like this:



(that's a hair not a crack)

[otolith]

Good coating of dielectric grease on the coils tried, no change.

[otolith]

Don't think there is any water getting in, it's as dry as Ghandi's flip flop under the cover, but that's interesting - what symptoms did you get, and did you see a CEL?

[otolith]

Interesting, thanks. The lack of any warning lights is puzzling. Will find out tomorrow morning if it's logging any codes.

[otolith]

CEL appeared on the way to the garage. There is definitely a lack of power everywhere now. I've left it with Simon at BK and brought the Yellow Peril home, hopefully there will be news later.

[otolith]

Misfire - but he's cleared it and it hasn't come back. The guys who did the reflash (Essex Autosport, used to be Sinclaires) did say that it could throw a CEL at first, but it didn't do so before today.

It's just frustrating not being able to rule out the reflash - I don't think it's the cause, because of the history of intermittent problems, but it's impossible to tell. Simon is going to see if he can find someone willing to try an ECU swap to see what happens. He's ruled out plugs, problems with sensors, fuses, catalyst seems OK.

Basically, if you keep the throttle pinned, it feels like a massive flat spot from about 6000rpm to a bit over 7000rpm, when it starts to pull again. That's with the cam change at about 5700rpm.

[otolith]

Still not fixed. I've had some suggestions from the Celica owners club - broken lift bolt is a possibility, but it would seem to be rare on Celicas post-'02 and pretty much unheard of on Elises (unheard of by Lotus, anyway). Other suggestions are blocked filter on the oil control valve (part of the hydraulic mechanism for engaging lift) or an issue with the vvti pulley.

I'm trying to get in contact with a 2ZZGE specialist they have recommended.

[otolith]

The bloody thing just decided one day that it wasn't going to do it any more, and hasn't since - so I'm none the wiser as to what the actual problem was. Infuriating!

[otolith]

I know the feeling! I'd like to get it on a dyno somewhere that knows them, just to be sure it's now making all the power it should, but it definitely feels right. If you do get to the bottom of yours, I'd be very interested to know what it is.