10 replies to this topic

[alicetheauto]

Had to work on a mates car today. Its a mainstream Cooper, K-reg SPI. It has done 100k miles. It smokes VERY badly, from startup. Is this likely to be from worn rings? Or is it possibly something ECU based? Brand new plugs are already coked up and thick black in under 5 minutes of running.

We spent 3.1/2 hours tonight trying to remove the lambda sensor tonight, ended up having to undo the RH engine mount and engine steadies, move the engine forward, drop the lower downpipe out the bottom then move the throttle body to one side so the manifold would come out the top. It was VERY coked up, so is going to be replaced. Is this likely to be the cause of the apparent overfuelling? Or is it more likely an effect? I told my mate it would be easier to rip out the SPI and drop one of his MG metro carb lumps in.... There is so little space to work!

[Darkscamp]

changing from spi to carb isnt as easy as it sounds, as i'm finding out.

wiring, fuel regulators, the list is endless.

the lamda sensor will have an effect on fueling but i would say its due a rebore to 1293.

just a thought, have the valve stem seals been replaced recently as they will cause smoking on startup. if its constantly smoking heavy then i would say ring and bores. mine was overfueling and i ended up re-honing it due to bore-wash from the extra fuel.

[alicetheauto]

It has been laid up for 18 months. No attention at all in that time... I have just found a specific socket to take out the lamda sensor, and feel really stupid for dismantling half the bl%%dy car!! Its so simple! Lamda sensors are from £55-100 though to replace! I thought they'd be a tenner! Will keep looking.

[Darkscamp]

if you do buy a lamda, search online as i got one for £55 which had the correct connector for the loom, otherwise if you buy the universal one, you will have to cut the cables and use bullets, which i have heard can cause slight issues with emission signals.

[alicetheauto]

Ook cheers, will do. I am going to try a few trade outlets first though, I dont think my mate will like £55 for a "cheap turnaround" project in his garage!

[THE STIG]

if he intends to keep it uses a good lambda sensor

you can get them for under £20 as it just have to be a 4 wire lamba two are heater wiers ones ground the others signal if you buy a universal one will not last as long aas a genunie replacement

if you get a universal solder the wires dont use bullets as will corrod and affect the siganl

[Simoncarter1]

when re-installing all the parts, its worth changing the water temp sensor under the inlet manifold, these often go wrong, infact its probably the cause of all this.

it tricks the ecu to think its cold all the time, and therefore runs it as if its on choke.

its probably the most common problem with the SPI mini, other than all the small air pipes that run from the back of the intake manifold to the ECU.

trust me, check/replace the water temp sensor.
its green.

hope this helps

[martin_stgeorge]

i have an old lamba sensor that i took off a mini when i relaced to a 3 branch. it seemed to work on my mini when i took it off and if you want it would not cost £50. i would gladly swap it for a red haynes mini manual if you have one. also the temp sensor i think only effects when the engine is cold.

[alicetheauto]

I have heard about these temperature sensors failing before. This car runs like this even from completely cold, so I had pretty much ruled out this sensor as the main fault. However, it could have been this that caused it to run poorly in the first place and then furred up the lamda sensor?
Martin, that must be about the only Haynes manual I dont have, is that the SPI/MPI book? Qhat sort of money would you be thinking, so I can let my mate know? Cheers.

[martin_stgeorge]

nd£10 all in and i will post tomorrow. i did clean one on a car with carb cleaner and it seemed to work after on a saxo vtr as it was running funny. just do not touch the end, i suppose you can try it, before you buy one.

Edited by martin_stgeorge, 19 November 2009 - 09:46 AM.

[alicetheauto]

Pm'd you!