Misfiring and some white smoke

[coopersg]

My Elan SE M100 (turbo) has started misfiring and running rough especially when I try to accelerate. When it misfires there's some white smoke from the exhaust. There wasn't any trigger or event that caused this as far as I'm aware. It used to start perfectly with no throttle required, now it's a spluttering noise until it gets going.
I don't have much confidence when it comes to taking the engine to bits, but does anyone have any suggestions?

I live near Aberdeen (St Cyrus). Having seen posts from other Elan drivers in Aberdeen I'd be pleased to meet up. I doubt if the car would make it though!

Cheers,
Stewart

[epipete]

Coil Packs?

Can you detail a little more about the nature of the misfire?

[Jamie N]

Sounds also like early Head Gasket failure, hopefully it aint though as its not a pleasant days work.

[John_W]

Hi, Stewart.
I think I saw your car on the "Drive-it Day" trip from Aberdeen to House of Dun at the end of April. I noticed it parked (obviously you weren't doing Drive-it Day) outside a house on the left side as I headed south. Green from memory.

Anyway, try the simple stuff first. Before you get to expensive stuff, some of the cheap things that can cause a misfire are plugs not being properly gapped, early signs of Hall sensor failure or a coil pack on the way out. If the timing marks waver a lot when you try to set static timing, I'd look to the Hall sensor.

Good luck and keep an eye open on LEC and we'll let you know when the next bbq or whatever is.

John

[coopersg]

Thanks for the replies. I will start by checking the plug gaps, as that's within my capabilities. Thanks John. No, mine is red, and I live well off the A92 in an old small-holding. It wasn't me. Do let me know when/if there are any events locally thanks. Can you recommend someone locally (Aberdeen area) that could give the car a good going over? Have you heard of or used Ricky Gauld?

I don't really know how to describe the misfire, other than it behaves just like an old 60's Mini if you got damp in the distributor. Splutters on starting and if you're driving along at 40 in 4th and put your foot down it just fails and splutters. No backfiring though. Sadly, I don't expect to find the solution myself, and I wouldn't approach a cylinder head gasket change although I have in the past (on an old 60's Mini ).

It recently had the gear cables replaced and I've seen mention in this forum of damage being done to other parts of the engine when that is done. But it ran for about 100 miles after the replacement before this issue developed.

Cheers,
Stewart

[epipete]

Still sounds electrical to me - Coils, Ignition Leads, plugs, after that I'd look at fuelling - failed fuel pump maybe?

I see no reason to suspect HGF but you could check for the usual signs.

[Rambo]

Whilst you're poking about, try a paper clip test. It is worth doing this routinely anyway as any faults will be stored and you can narrow down problem areas.

Its very easy to do and takes less than 5 minutes

[roy666]

Hi Stewart. I had the same problem. Look at my "Rough Running Engine - White Smoke" post. Was a head gasket which I had to replacement: signs were loss of coolant, slightly mayo on the oil dip stick, rough running on start up. Get it checked asap. Mike.

[coopersg]

Again, thanks for all the replies. I took out the plugs, checked the gap, and they were all correct. The plugs were also clean - not oily. They were replaced about 150 miles ago anyway.
I replaced the plugs and cleaned up the HT leads with a cloth and WD40. They were pretty dirty, and probably quite old. I only cleaned them as far as I could reach under the coolant expansion tank. After I did that I started the car and the misfiring is now different. It doesn't misfire at high revs, only low revs. In fact it does manage to tick over, but it is running on 3 at those revs I think. Increase engine speed and the misfire stops at about 2200 revs upwards. If it was a coil it would probably misfire at any engine speed.
There's no mayo, and the coolant is clean. Yes, there's a little black oil on the inside of the coolant cap, but that's always there and returns after cleaning.
No errors on the paper clip test.
So I think the problem is probably HT lead related? At £90 a set I'll have to save up my pennies for them. The car's already cost a fortune this year.
Again, thanks for all the suggestions.
Stewart

[Fredjohn]

You can get much cheaper but equally good leads for far less than the price you stated.
I bought some Kingsborne leads from the US (various colours, 7mm or 8mm dia, 8mm preferred) for about $27 plus postage to UK.

See this website

Well worth it as my leads were pretty old and I had a very very slight miss-fire under load which has now gone

[muley]

Hmm white smoke under load?

This was a symptom of my turbo failing.

Take the turbo inlet hose off and check to see if there is any play in the impeller. There should be none.



Jim

[coopersg]

Thanks FredJohn. Have ordered a set.

Jim, I think the white smoke is a red herring as it's very minimal and I didn't see any today when I was testing.

I'll try new leads anyway, as it can't do any harm.

Cheers,
Stewart

[HJ2]

Hi Stewart,

At the risk of double posting.... What's the state of the coil packs? And when you take the plugs out, are all the same color / state?

Pascal, It would help if you make your own topic I PM-ed you allready, but if we keep it on the forum anyone else with the same problem will benefit And there are more people who can help you out as my knowledge is limited.

[Enright]

If coil packs have never been changed my money would be on those before the leads - coil packs almost always seem to wear out first. Cheaper too.
But check base timing first because it can wander, and fixing that is free.

[John_W]

If coil packs have never been changed my money would be on those before the leads - coil packs almost always seem to wear out first. Cheaper too.
But check base timing first because it can wander, and fixing that is free.

and when you check base timing, if it is erratic, look to the HES.

[coopersg]

I fitted the new HT leads today which I got from Kingsborne and the misfiring problem remains. So I will change the coil packs as recommended by Enright. Can someone recommend the best source/type in the UK?

Thanks
Stewart

I will persevere with the original thread and this issue until I resolve it, but this thread seems to have wandered somewhat!

[HJ2]

I have the MSD coil replacements and are happy with them.

[coopersg]

How about these NGK coil packs on Ebay:

http://www.ebay.co.uk/itm/New-NGK-Ignit ... 1e9e6c1075

I see no reference to NGK in the Wiki or the forum which is strange.

Stewart

[John_W]

... the base timing was set by Franck FVH and I remember he has difficulties to do it despite his great experience. Could something else be erratic and pollute his setting ???
1° Also, he made this more than 2500 km ago, could this change spontaneously ? How often do you set the base timing ?

... early signs of Hall sensor failure or a coil pack on the way out. If the timing marks waver a lot when you try to set static timing, I'd look to the Hall sensor.

and when you check base timing, if it is erratic, look to the HES.

If it is difficult to set the static timing because the timing marks waver, suspect the Hall effect sensor.
The base timing does need resetting from time to time, but not after only 2,500 Km.
John

[GeoffSmith]

I will persevere with the original thread and this issue until I resolve it, but this thread seems to have wandered somewhat!

Perseverance pays dividends! Pascal's problems have been separated from yours as it was confusing the hell out of me too.