Just the fact of being Titanium is not going to make it worse, or create the misfire.
Titanium plugs (or Iridium) are not highy regarded in the racing world, only in the street world. You’ll find most race engines run with normal plugs, as the fancy ones don’t actually give more power.
The only case where they could create a problem (and this happens with the normal plugs as well) is if they are the wrong temp range.
And I think Rox is the one here that has experimented more with that (since he had the wrong ones installed by the dealer )
Just don’t follow the marketing hype and just install normal plugs. They cost peanuts and is good insurance.
I’ve just driven to a meeting and back and suffered the 5500 rev limit 3 times, twice whilst half way through an overtaking manoeuvre which is f***kin dangerous. I am stuck for ideas how to sort this out, has anyone got any tips apart from the plugs, leads and speed sensor as I�ve been through all of these? All ideas gratefully received.
The 5500rpm limit on the new ECU takes effect if you have a genuine misfire.
Sounds like, rather than being a plug or wheel sensor thing since you have tried those, it is an actual problem and the 5500rpm is just acting to protect the engine.
Better for it to do that than for it to ignore it.
Have you taken it to a Lotus place to analyse the error code given by the ECU yet?
There was a definite misfire before I changed the plugs, you could feel and see it as it would cause the tacho to flicker. Since doing the plugs and leads this has gone away although I did feel a very slight stutter the other day before the 5500 limiter cut in. I don’t know what Lotus would do other than hypothesise as to the cause like I am at the moment and I would rather do it between myself and other owners/experts than pay for Lotus to do so. I can see why the 5500 limiter is a good idea if you run a CAT, which I now don’t, but it is so dangerous when it kills all the power whilst half way through overtaking. Do you know if the ECU is advanced enough to locate the cause of a misfire or can it only detect a faulty sensor? If examining the ECU logs is the only way I can cure the problem then I guess I will have to take the car to the dealer.
I think I’m going to replace the coil pack as that is the only thing I can think of too. Thanks for your help and suggestions guys. Much appreciated as always. I will let you all know how I get along in case anyone else suffers the same issue.
Sledgehammer to crack a nut, perhaps, but there are all sorts of other advantages, such as instant control over MOT fuelling, adaptability to ongoing tuning etc etc
I have no stutters with my Exige, needless to say (touch wood, fingers crossed!!)
By the way going to take the car to Lakeside and get the plugs checked and if anything other than the the standard ones I’ll have 'em replaced. Thanks all for the assitance as always
I’m on the other side of the country - about 80 miles from Edinburgh, which is a shame, or else I would take you up on your offer of beer.
That sounds like a good excuse to drive your car 80 miles across deserted Scotland doesn’t it??! Or even better meet halfway and you both get 40 miles then! Better make it a round of Shandies though.
If the coil pack is a standard Rover item then I doubt that we will get it from Lotus. Does anyone know if this is the case?
The Emerald route is definately one that I intend to go down as my car is currently only a 177 and I would prefer to have the extra flexibility over the Lotus ECU. This has to wait for a bit though as Ive been spending a bit too much money on my car recently. If the coil pack is bust though I will have to fix that anyway.
Plugs and fuel…
Iridium plugs arn’t the choice of racers as they change the plugs every race anyway…iridium come into their own on the street where they can last 60,000km’s in a properly working car. Please show me another spark plug that can do that and survive 20+psi of boost every trip. Also worth noting is that they come pre-gapped (don’t try to re-gap thenm you’ll break 'em) - so you don’t have to worry if you’ve got the gap right. (which could be another cause of your misfire)
Anyway - if someone can give me the NGK part no. for the stock plugs I can give you the Denso Iridium code. Which you can take to your local Partco (�8.50 per plug usually - expensive yes but they last longer).
Has anyone tried using better fuel like Optimax to get rid of these mis-fire’s? optimax reduces det in turbo cars maybe it can burn better in an NA and make the difference?
If its trapped heat which is the root cause, has anyone bought a Pacet (or other) leccy fan and rigged it up to suck air out of the engine cover? Not ideal and its extra weight but it may overcome what sounds like a bit of a design flaw.
Plugs and fuel…
Iridium plugs arn’t the choice of racers as they change the plugs every race anyway…iridium come into their own on the street where they can last 60,000km’s in a properly working car. Please show me another spark plug that can do that and survive 20+psi of boost every trip.
Hi Axle,
I feel that you talk mainly of other types of cars, as I can assure you NOBODY will even remotely consider leaving their spark plugs that long, hell, we don’t even expect the engine to last that long .
I change them at about every 6000 miles.
Also, Exiges are Normally aspirated.
Fine wire plugs were designed really for other purposes, like avoiding fouling (as they can easier create a spark in less than favourable conditions) at lower revs and incorrect mixtures. Perfect for the typical street driver that doesn’t care about tuning and just wants to use the car only filling it up with fuel.
Iridium then is the best there is among the fine wire models.
Has anyone tried using better fuel like Optimax to get rid of these mis-fire’s? optimax reduces det in turbo cars maybe it can burn better in an NA and make the difference?
We pamper the Exiges here to a level that is often considered ridiculous.
Only the best fuids, and Optimax is our normal fuel, if not, BP super plus.
If its trapped heat which is the root cause, has anyone bought a Pacet (or other) leccy fan and rigged it up to suck air out of the engine cover? Not ideal and its extra weight but it may overcome what sounds like a bit of a design flaw.
not worth it, there are easier cooling mods, but they’re not good if a particular piece has given up, like the (dual) coils.
That sounds like a good excuse to drive your car 80 miles across deserted Scotland doesn’t it??!
Ian
IDG
nice idea… however, its across the central belt… which is the busiest, most boring crappy A road, dual carraigeway and motorway riddled part of Scotland there is…
If the coil pack is a standard Rover item then I doubt that we will get it from Lotus. Does anyone know if this is the case?
I’m not actually sure so if you manage to confirm could you let us know? Although I have a feeling that AndyD, RussT and Phil may know this already?? - I know its not the same as a standard elise but ain’t sure if the Rover VVC engine maybe uses a wasted spark system? in which case maybe its the same as an MGF or MGTF ??
Nah - just used to work there - and have family still working there.
And yeah I know more about the spark requirements of Turbo charged engines…
Can’t argue with NGK…just offering to find an alternative…if there is one. I’ve got access to a db with all the denso plugs, iridium, platinum and normal.
Got it wrong - car has the correct plugs in it so 5,500 limiter not caused by that - have to presume it was heat build up and keep an eye on it.
To keep up the pampering oil changed and full tank (and spare fuel cans) of Optimax whilst was getting plugs checked so ready for Silverstone GP on Monday now
Thought you guys might be interested to know the best place to get a coil if you ever need one. The coil is actually a Vauxhall part (2.0ltr 16V calibra or cavalier) but Vauxhall actually charge more than Lotus . It is made by Bosche and the part no. is: 0221 503 001. I have searched around and the best price I have had is �82 inc VAT and delevery from 24/7 Spares. The number to call them on is: 07973 315 349. It should be delivered tomorrow and I will let you know if it solves my misfire.