36 replies to this topic

[minisprite1275]

hi all

proberly a silly question but can you just bolt on a new stepper motor ?

im having trouble with my spi (1994) when the car is warm it some times cuts out at junctions.

when driving it seems like its missing at times,when on or near full throttle

any help would be most welcolm

[FlyingScot]

hi all
proberly a silly question but can you just bolt on a new stepper motor ?
im having trouble with my spi (1994) when the car is warm it some times cuts out at junctions.
when driving it seems like its missing at times,when on or near full throttle
any help would be most welcolm

Better to start your own thread, there are many reasons for the symptoms.

FS

[MR J]

Well, the code reader arrived. Connected it up and there where 2 stored faults. 02 inlet air temp sensor circuit fault and 16 throttle pot circuit fault. I cleared these and they didn't come back, I've been driving the car for 2 days and it seemed to be ok, felt really smooth and was idling fine.

Took the car for MOT this morning and it drove there nice, I left it with them as I'd got other stuff to be getting on with, when I went to collect it they informed me it had failed the test on emissions and it was cutting out and very jerky. It was virtually undriveable on the way home, I had to keep the revs up to stop it from stalling and it's now got a massive flat spot when you go to pull away.

Tried the code reader and it's showing no faults and all the live data seems to show good data that everything is working fine.

[minisilverbullet]

what do you mean by good data? what are the figures. 

[MR J]

what do you mean by good data? what are the figures.

Water temp 75
Inlet air temp 44
Map 023kpa (running) 100kpa stood
O2 between 0 and 1.8

Not too sure if the O2 is fluctuating too much.

[MR J]

https://youtu.be/zo6bp1gB5bQ

This is the live lambda data.

[minisilverbullet]

44 air temp seems high.

[MR J]

44 air temp seems high.

I'd have thought that was quite normal for an under bonnet air temp?

[MR J]

Now not so sure on the stepper motor issue, it seems to be operating fine throughout it's range when hot and cold.

 

New ignition parts ordered and also a new lambda sensor, going to also strip and clean the throttle body over the next few days.

[FlyingScot]

44 air temp seems high.

I'd have thought that was quite normal for an under bonnet air temp?

Seems high to me too and by way of comparison....
ECT 80
MAP 28
RPM 850
IAT 24

It quite cool here today at around 7.5c but with my Spi warmed up and standard air box the inlet air is just 24C.
Are you running a K&N cone by any chance ? As otherwise the IAT seems too high to me.

FS

Edited by FlyingScot, 26 April 2015 - 02:05 PM.

[FlyingScot]

What the condition of the coil? Just a thought when I re read your symptoms.
I had a Sidewalk that had intermittent cut outs and then running like a pig, turned out the coil was on its way out and it showed itself only when hot.
There's a pinned FAQ about ignition coils (also checked somebody hasn't fitted the wrong one meant for older minis)

FS

[MR J]

Yes, its got a K&N cone filter filtted.

 

I'll test the inlet air temp again when its cold. I fitted a new coil about 3 years ago but i suppose it could be failing.

 

What are your thoughts on the live lambda data? Should it be switching as far as 0.0v and 1.8v?

Edited by MR J, 26 April 2015 - 04:19 PM.

[MR J]

Just checkedon the live data for the IAT, it's reading ambient at 12 deg cold.

[Fast Ivan]

check your coil, as FS mentioned above

[FlyingScot]

Okay seems the IAT could be right, lambda looks okay, I'm less and less convinced of the absolute number as long as it's moving quickly up and down.
Check it's the right coil too, I have see cars with the wrong one fitted which subsequently failed.
KernowCooper has a guide here http://www.theminifo...tributor-types/

FS