10 replies to this topic

[Colley345]

Hi,

 

Got a dreaded issue with my 95 Spi. My first forum post so apologies for vagueness etc. 

 

My mini is struggling to maintain idle. On startup from cold it takes a decent few cranks before finally firing up. once it has started, it fails to self-regulate at idle, often stalling near enough instantly unless you feather the throttle a little. Sometimes it can keep itself going for over 30 secs as it hunts before dying but it does vary. 

Regarding the cranking, once its up and going it takes less effort to restarting off stalling. However this long cranking reoccurs when back to cold.

 

You can drive it fine...until you hit a red light and have to go back to feathering the throttle to stop itself from stalling. Once it warms up, it struggles far less, although still not near stable.

 

Done a lot of digging around on here, read Sprocket's brilliant and detailed guide on Spi's.

I have checked vacuum lines, replaced lambda sensor and checked relay, indexed throttle, replaced air temp sensor.

 

And that's where I'm up to.

I realise using a scanner can make it far easier to isolate a problem like this on the spi.However, before I consider that investment at all, is there anything you guys can think of that would be best to check next and how?

 

I'm going to do further checks on the stepper motor as I know that is an area that could be at fault.

 

Thanks,

 

Alex  

 

 

 

[RooBoonix]

Stepper motor would be my first port of call. With the ignition on, and pumping the throttle say 10 or so times you should hear the stepper click a load and reset it's position. If it doesn't then I'd be checking the wiring to it, and the stepper itself.

 

Of course, if you had a scanner you can make the stepper go through it's motion..

 

Thanks,

Cam.

Edited by RooBoonix, 01 December 2017 - 09:27 PM.

[FlyingScot]

Something well wrong, the beauty of the SPi is that it starts easily. Borrow a code reader or be prepared to keep guessing (or have others guess for you). These cars were designed to be plugged in and it isn’t easy to diagnose faults without this.

FS

[hunterg30]

check all vacuum pipes and connections,could be temp sensor, do as others have said and get a code reader on it

[Colley345]

Thanks for the pointers. I’ll give the stepper motor trick a go but you’re right, getting a reader would make this far less painful to figure out (aside not for the the bank balance!)

[sledgehammer]

while you save for a code reader - have you done the cheaper bits ?

 

you don't say about servicing the car in your post ,

 

I would replace / check - 

 

plugs , leads , rotor arm / cap , coil & coil nose & terminals all clean / tight , air filter , fuel filter , fuel condition (discoloured / water in fuel)

 

valve lash , inlet manifold gasket - check for leaks

 

simple cheap things 

 

I also check manifold vacuum  steady 17 - 22in  indicates all good - this chart is for mainly non injection cars but could still indicate where to look for other faults

 

http://www.classic-c...acuumgauge.html

 

also it is surprising how setting valve lash / rocker arm gap , can improve compression / improve starting

[genpop]

Hello,

prior to buying a scanner, I would change the coolant temp sensor and the gas filter.When changing the CTS you can easy check the conection of the electric heater beneath intake manifold too.

[RooBoonix]

Mine doesn't have an electric heater element (the element shattered and I didn't bother replacing it, too expensive and I never noticed any difference) and mine never has an issue starting. If it's there and working then connect it, but it's not 100% essential and helps out more with cold running rather than starting I believe.

[genpop]

@RooBoonix

the heater element was only a hint, when he has the manifold off, he may look for that. I think the CTS is defekt or not connected.In this case the ecu (limp mode) thinks there is a warm engine and gives less gasoline to the engine.

[Colley345]

Wow really great responses. I've done a few of those service items already. Plugs, leads, checked rotar arm and cap. I have a coolant sensor on order already which is good and will check out all other things mentioned. Stepper motor is moving and resetting but I suppose it could be still causing issues (to be inspected further with scanner). 

 

When I have the time, I'll give all those tricks with the heating element, fuel filter and pressure as I search for a scanner.

 

Much appreciated! I'll report back when I try them out

[RooBoonix]

@RooBoonix
the heater element was only a hint, when he has the manifold off, he may look for that. I think the CTS is defekt or not connected.In this case the ecu (limp mode) thinks there is a warm engine and gives less gasoline to the engine.

Absolutely. That is a good theory there, definitely a possibility. Was worth a mention