60 replies to this topic

[AgentHubcap]

I've been trying to solve an issue I'm having with my mini for a couple of weeks.  I have an early Japanese spec SPI and when the engine is cold the car will not accelerate.  

 

I've checked the vac hoses and found them to be replaced with aftermarket rubber hoses.  

Plugs have a good colour (doesn't look to be running rich)

The temp gauge never reads half way (normal operating temp).  The highest I've seen it is 1/3.

 

Is there anything else I should be checking for before I start randomly replacing parts?

[FlyingScot]

 image.jpeg   32.86K   3 downloads

Check the TPS (throttle position sensor) and if it's an early SPi the throttle switch but low temperature reading indicates coolant temperature sensor (CTS) fault as the sensor feeds the ECU which in turn feeds the gauge.

Plugs on an SPi usually visually look a little lean.

Vacuum pipes and the fuel trap are the usual suspects as you can read.

FS

Edited by FlyingScot, 30 November 2015 - 08:36 PM.

[spiguy]

How long does it take before it seems to be normal? My '92 SPi is pretty gutless when cold, but then I nurse it for a few minutes when cold anyway, then once it starts to warm up it's fine.

[AgentHubcap]

How long does it take before it seems to be normal? My '92 SPi is pretty gutless when cold, but then I nurse it for a few minutes when cold anyway, then once it starts to warm up it's fine.

 

Took me around 7 minutes this morning.  I'm starting to think my CTS is bad.

[spiguy]

Hmm, on that basis, I'd be more inclined to suspect your thermostat is not working correctly, ie partially or completely stuck open. What you seem to have is a longer than usual warm up phase, coupled with a low reading temperature gauge. That would be explained by an open 'stat. Is it cold over there just now?

[AgentHubcap]

It was below freezing yesterday.  I initially thought it was a stuck thermostat, so I replaced it last weekend.

[Alpenflitzer]

Qote: "I've checked the vac hoses and found them to be replaced with aftermarket rubber hoses."

 

Vacuum pipes should not be made of rubber. They are supects to be pressed together. It should be silicon 3 mm ID

[Alpenflitzer]

It was below freezing yesterday.  I initially thought it was a stuck thermostat, so I replaced it last weekend.

 

 

 

What temperatur is the cooling thermostat?

 

What kind of spark plugs ? Is the heat-value correct?

Edited by Alpenflitzer, 01 December 2015 - 04:42 PM.

[AgentHubcap]

Qote: "I've checked the vac hoses and found them to be replaced with aftermarket rubber hoses."
 
Vacuum pipes should not be made of rubber. They are supects to be pressed together. It should be silicon 3 mm ID

I have an order for new vac lines just in case, but they looked like they were in good shape.  I would expect the car to run like crap all the time if the vac lines were wrong, though.

Thermostat is 88C.  Not sure what the plugs are, I'll check when I get home from work. 

Edited by AgentHubcap, 01 December 2015 - 07:18 PM.

[AgentHubcap]

Plugs are champion N9yc and look like this:

 

 

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[peter-b]

Mine takes about 5mins before you can drive it in winter/cold weather, not too bad if you're not in a hurry to get going. During summer here it's not as long, normally a minute or so.
If you try to drive it stone cold, does it seem to die like its out of fuel. I tried all sorts of 'fixes' but nothing that's worked yet.

[Alpenflitzer]

Plugs are champion N9yc and look like this:

 

 

The spark plug indicates a  very, very dry mixture or this is the wrong spark plug anyway.

Champion should be RN9YCC which is quite different to what you use.

 

 

From my experience best sparks are either

NGK BPR6ES with 0.9 mm gap   or

BOSCH Super Plus (WR7DC+) 0 242 235 663  with 0.8 mm gap   or 

BOSCH  SUPER 4 (WR 78) 0242 232 504 H  0.8 mm gap

 

I found Bosch and/or NGK are the best for an SPI

 

Mine takes about 5mins before you can drive it in winter/cold weather, not too bad if you're not in a hurry to get going. During summer here it's not as long, normally a minute or so.
If you try to drive it stone cold, does it seem to die like its out of fuel. I tried all sorts of 'fixes' but nothing that's worked yet.

 

Oh la la.  I hever never heard of such a problem. Could you describe a bit more how it starts, what is the UPM when it is cold, what is the UPM when you finally can drive your way?

Edited by Alpenflitzer, 15 December 2015 - 05:39 PM.

[AgentHubcap]

When cold, it will barely accelerate, even under wide open throttle.  I'll take a video tonight to demonstrate.

Edited by AgentHubcap, 16 December 2015 - 08:23 PM.

[Alpenflitzer]

The deposites on your sparks are mainly from Oil and gasoline additives. It can also bei a hint to defect Valve guides/seals or piston rings.

Such a spark picture on the other hand can be produced due to very long and often running in idle.

 

This is from an official BOSCH brochure with pictures.

[peter-b]

[quote oh la la.  I hever never heard of such a problem. Could you describe a bit more how it starts, what is the UPM when it is cold, what is the UPM when you finally can drive your way?[/quote]

Starts perfectly, idles fine at about 1500 (cold) then about 850 hot.
It's just if you want to jump in and take off straight away when its cold. It actually feels like its too lean, no back fire or hessitation, just gets slower and slower till you are actually at about 900-1000 rpm. If you just use about 1/4 throttle it'll limp along for about 1/2 kilometer then cruise away fine. I've tried nearly everything, plugs, cap,rotor,leads, pump,filter, temp sender, throttle body o/h. All the tiny hoses are brand new and on right, even a new wiring harness. Only thing else could be is ECU but I have just got used to it.
Gunna spend some money on it in about six months, do the motor and a 5 speed box, might ping the injection off and fit carbs.