Lotus Elan and Lotus Elan Plus 2 Forums

Hi all,
Im just about to get my Hillclimb Elan back on the road but it wont start very easily. A quick spray of fuel into each inlet and it fires straight away and runs like a dream. All ok with fuel pumps etc and worked well before re build. Ive never messed with the settings or plugged in the laptop (yet) as it has always run so well. Has anyone here any experience with this type of set up? Any ideas would be g8 before I spend more!
Many thanks,
Jon

My Twopenneth

Having had a rebuild the engine might be "tight" and the battery voltage when cranking could be dropping so low as to cause problems re. Emerald/Injectors?

John

Thanks John,
Seems to turn over better than ever and has new battery but just wont fire. In some notes I've read that the ecu should be earthed directly to the battery but I cant see what difference that would make and it wasn't that way before. Fuel pressure is fine at 50psi and as said it starts first time if you spay a fuel mist in the trumpets.
J

Jon,
Others don't agree with me on this theory, but the age of the petrol in the tank is a big factor in poor starting after a long layup. The map with your emerald will include enrichment for cold starts but can't take into account fuel that has lost a bit of octane rating, squirting a bit of fuel into the inlets merely enrichens the fuel air mix enough to make the engine start easily.

If your tank is low, just adding 10 litres of fresh super plus will cure it. If I'm wrong you won't have spent money on unecessary parts.

It's worth understanding how the map works and being able to tweak non important things, if you don't already have it you can download the software from Emerald and various base maps. Plugging in the laptop enables you to download and save the map that is present on the ECU, you can then carefully tweak items like rev limits, fan cut in points and adjust cold start enrichment safe in the knowledge that you can go back to the original map. I would leave the other settings well alone. You can practice adjustments offline before loading them into the ECU.

One of the problems with a bespoke ECU like Emerald is that there is only one chance per day to set up the cold start map, as obviously once the engine coughs into life it immediately begins to warm up, so if it started sort of okay and you think it needed a bit more or a bit less advance or enrichment you need to wait until the next day to be sure of testing the theory. Base maps contain a startup map that is known to work okay on the type of engine it was written for, but may be far from perfect if your state of tune differs significantly from the engine the base map was written for.

I have Emerald and Jenveys on both my cars, the +2 zetec starts first time every time after I tweaked the startup map a bit, the S4 duratec is a bit finicky, but still starts well enough, I'm more interested in driving it than playing with the Emerald at the moment

Regards

Alan

Jon,

I agree with Alan, The Emerald is a good bit of kit it has a "start up" map. To avoid confusion it works in conjunction with the main "running" map. By this I mean on start up it uses the start up map then switches over to the running map when its told to. This is generally at a preset temperature similar to an electronic choke.

It may be that this portion of the map requires some tweaking. If you want I can send you the maps I have for Twincam @ 1650cc and 126bhp, Crossflow @ 1700cc and 135 bhp. These came on the Emerald CD with the ECU.

Hope it helps.

Paul

Thanks for your replies. I have a disc that came with the car so will have some fun in the morning and see how it all works. Hopefully it will all make sense! The engine is 180bhp and I recall the previous owner said there was a map on the disc for it.
Thanks again and I'll let you know how it goes.
Jon

Hi!
- just an idea based on practical experience: if the engine is not starting when cold (does it start when warmed up??) it could be a temperature sensor, if so, most probably the water temp sensor. Especially after an engine rebuild, maybe a loose connector or something in that direction? Also, the throttle position sensor not adjusted properly could lead to some misbehavior.
If you can hook up your laptop to the ECU you should be able to read the various parameters without interfering with the map. Might be a good idea to check the various bits/sensors before spending time, money and nerves on the electronics. This does not mean - how Alan pointed out - the petrol is ok; especially if you have added some additives; they can have an impact on petrol characteristics over time.
Keep us informed!
Cheers
Csico

After finding a compatible laptop with the old fashioned ports I finally got in! Everything seems to be working properly. It seems that the problem is coming from a voltage issue with it dropping to under 7 while starting. The battery is brand new but linking another batteryTo the existing one enabled enough volts for the car to start.
The ecu does not want do it's stuff below 9 volts.
This leads me to think that it could be an earthing problem or starter motor? Directly wiring the earth lead to the battery brought the ecu voltage level up to 9v.
I'll try that again in the morning before looking at the starter motor and hopefully work things out.
Thanks again for advice,
Jon

Just tried this morning and no joy! Felt the earth terminal on the battery after trying and it was quite hot. I changed the connector to a thicker one and hey presto it starts on the first turn of the key!! I have no real idea why but off to get it mot'd later. Very relieved.
Hopefully that's it?
Thanks

jon1986eac wrote:Felt the earth terminal on the battery after trying and it was quite hot.

Hi!
good that the problem is solved. Could it be, that the electrical connection between the terminal and cable kind of disintegrated for whatever reason??

Csico

Tried it this morning and guess what? Wouldn't fire! It did eventually but very reluctantly and of course no problems after it had run for a moment. Battery terminaly was fine but noticed conection to the isolator switch was warm and of the same thin type so that will be changed.
Time to call in an expert.???
On the plus side it drove fantastically and past the MOT with flying colours.

I restarted my Elan today for the first time in 15 years, its only the second time that the motor has turned in 25 years

Sometimes simplicity cant be beaten, I have a lawn mower fuel tank gravity feeding the carbs and the plugs, points and condensor apart from being cleaned and reset are the ones that have been there for at least 25 years.

To my great surprise she started within a few turns and ran sweet as a nut

I only ran her for about one minute, after lunch I will do another compression check, give everything a good look over and then run her for a few hours to scour the oil and coolant systems.

Jon
Ecu's and fuel injection don't like low voltages,especially during cranking,make sure you have a feed and earth of adequate gauge direct to the battery with good connections (all of them),make sure the battery is in good condition and lastly the same for the starter motor as this is what causes the voltage to drop....

John

Thanks John,
Looks like Its getting better and started with reluctance at least this morning. I will check the carbon brushes in the starter motor as Ive heard the dust created can cause problems!
Its all just a bit frustrating seeing as though it started oh before.
My first event in a couple of weeks at Wiscombe so hopefully sorted by then.
Jon

Jon,

Hi, I know it's been a while since a post on this subject but how are you getting on?
Just a small addition that has come to mind, have you reset the TPS? It may be benificial,easy to do.mine had problems starting untill this was carried out.

Paul