PLEASE HELP....Lotus Elise S1 Keeps Cutting Out

[s1elisedriver]

Hi all i am an elise owner from Australia, and had this problem a while back and guess what.. its back again. I have come to a point where i just feel like driving this car off a cliff grrr. After i found the original ptoblem i was having which was my fuel pump not priming and car not starting, i tracked it down to be corroded wiring in the inertia switch. Now that was all fixed i take the car out today in 35 degree heat the car stopped on me, i waited bout 15 mins drove bout 1km and it stopped again..it kept repeating this till i got home, mind you it took me nearly one hour to get home even though it happen from the next suburb up from me lol. I can only point to the problem now to be is the fuel pump itself, anyone else have similiar issues please get back to me, mind you this problem has been occuring for years, im to afraid to drive this car on a hot day and it is really pissing me off...

[UnluckyTimmeh]

does it only happen on hot days?

not that i imagine you have many cold.....

[s1elisedriver]

Well it was going good for about 6 months ago wen we cleaned the fuel tank and changed the fuel filter, it handled hot days, today its happened again. It mainly happens wen stuck in traffic for a long time or something, the car just gradually stalls, you have to wait a bout 15 mins for it to start and gets you another 1km, im only happy it happened near my house otherwise i would of had to tow it, anyhow does this sound like the fuel pump playing up?

[UnluckyTimmeh]

After it cuts out, and you go to start it again, can you hear the fuel pump priming?

Within that 15 mins, what does it do while not starting? all turn over ok? even try to fire.....

[s1elisedriver]

after it cuts out if i try start it again it starts then turns off straight away, i cant hear the fuel pump prime all the time.

[s1elisedriver]

I disconnected the fuel line that goes to the fuel filter and the fuel looks clean so Im buggered if I know what it is, its 27 degrees today and the car is running ok.

[UnluckyTimmeh]

Check the distributor cap and make sure it's not cracked. The rotors arm may be worn as well. Sounds like an electrical issue to me when hot...

[s1elisedriver]

Ok I will check the dizzy cap Wen I get a chance. There was an electrical issue before, the wires that go to the inertia switch were corroded, we fixed that.. what other wiring should I be looking for?

[UnluckyTimmeh]

s1elisedriver said:

Ok I will check the dizzy cap Wen I get a chance. There was an electrical issue before, the wires that go to the inertia switch were corroded, we fixed that.. what other wiring should I be looking for?

Jeez where to start.....

if you can get a multi meter onto the fuel pump once its cut out wouldn't be a bad idea...

but I mean given the wiring in that car is at least 10 years old now it could well be a break in the wiring loom.

I take it theres no lights on the dash before it cuts out? It definately sounds like an electrical issue.

You said you couldn't hear the fuel pump prime, although it starts but then immediately cuts. if you leave it for say two mins and then turn the ignition on, have a listen then and report back.

Do you think you could replicate it sitting on the drive? i.e. get it up to temp and eventually it cuts out? if so what is the temp guage reading? i wonder if its a faulty reading and the engine goes into some sort of fail safe... although, i'm not sure if they have one.

[spiralp]

My wife had very similar problems with her 1999 S1 in traffic during the (few) hot spells in the UK this summer. Local garage who have looked after the car for the last 8 years decided to replace the coil. This did not cure the problem, so I changed the MFRU (Multi Function Relay Unit). The problem has not returned, but it is not exactly hot here!

[UnluckyTimmeh]

spiralp said:

My wife had very similar problems with her 1999 S1 in traffic during the (few) hot spells in the UK this summer. Local garage who have looked after the car for the last 8 years decided to replace the coil. This did not cure the problem, so I changed the MFRU (Multi Function Relay Unit). The problem has not returned, but it is not exactly hot here!

Good shout, These do have a tendancy to corrode inside.

Might be worth a look....

[worldwidewebs]

spiralp said:

My wife had very similar problems with her 1999 S1 in traffic during the (few) hot spells in the UK this summer. Local garage who have looked after the car for the last 8 years decided to replace the coil. This did not cure the problem, so I changed the MFRU (Multi Function Relay Unit). The problem has not returned, but it is not exactly hot here!

My S1 111S was cutting out on me on trackdays so we replaced the MFRU. Since then no problems at all

[bordseye]

I also had a problem with the MFRU which turned out to be the plug working loose. However the cutting out was not temperature dependand like yours is.

In the old days I would have suspected fuel vapourisation but I dont think that can happen with fuel injection. So I guess its back to the old fashioned primitive checking approach. Next time it happens, open up the engine bay , take one plug out of the block and with the plug connected to the coil and resting on a bit of metal, turn the engine over to see if there is a spark. If there ius a spark then the problem is fuel.

Next step is to disconnect the fuel line at a suitable place and again switch on the ignition to see if fuel flows. Do this carefully . No fuel? Check the leccy supply to the pump.

[KingoftheNorth]

Hi!

I've experienced exactly the same kind of problems, I've checked vacuum in petrol tank, MFRU (I cleaned the contacts), but it all boiled down to a faulty immobiliser. I ordered a "Immobiliser bypass" from EliseParts, connected it and the problem is history!

It's worth giving it a try - the bypass cost £6,50! And connecting it is easy - after you've located the connector.

Regards,

Leif

[saaby93]

Mate changed the MFRU . It's pretty cheap on ebay £10?

[s1elisedriver]

Sorry for the delay guys, Timmeh ive tried what u said run the car to a high temperature and the bloody thing wouldnt cut out, I am going to changed the coil and MFRU and bypass the immobiliser just to eleminate these out see how i go, im pretty sure its a simple fix but finding the problem is like a needle in a haystack

[s1elisedriver]

KingoftheNorth said:

Hi!

I've experienced exactly the same kind of problems, I've checked vacuum in petrol tank, MFRU (I cleaned the contacts), but it all boiled down to a faulty immobiliser. I ordered a "Immobiliser bypass" from EliseParts, connected it and the problem is history!

It's worth giving it a try - the bypass cost £6,50! And connecting it is easy - after you've located the connector.

Regards,

Leif

Thanks leif, will the immobiliser still work after bypassing? where bouts is the connector located

[s1elisedriver]

bordseye said:

I also had a problem with the MFRU which turned out to be the plug working loose. However the cutting out was not temperature dependand like yours is.

In the old days I would have suspected fuel vapourisation but I dont think that can happen with fuel injection. So I guess its back to the old fashioned primitive checking approach. Next time it happens, open up the engine bay , take one plug out of the block and with the plug connected to the coil and resting on a bit of metal, turn the engine over to see if there is a spark. If there ius a spark then the problem is fuel.

Next step is to disconnect the fuel line at a suitable place and again switch on the ignition to see if fuel flows. Do this carefully . No fuel? Check the leccy supply to the pump.

thanks, i have tried both, yes there is spark and yes there is fuel flowing.

[s1elisedriver]

i had a look for the immobiliser today but ill be buggered if i can see it, all that's there is the ecu box.

[s1elisedriver]

i think ill just replace the MFRU for now see if that solves the problem and worry about the immobiliser later