27 replies to this topic

[idlethumbs]

Hi all

My spi is starting to do my head in and after some help If possible.

Background of the car.
1275 cooper spi.
Engine rebuilt to 1293. Spi sports cam, stage 3 head. Rebuilt and head work by Mr Calver.
When the engine came back to me I refitted it with a new main wiring loom.
Car has never run right since refitting the engine. Idle is very poor, soon as you dip the clutch the car stalls. You can just about keep it going if you let the revs drop the engine sped to 1000 or less before sipping the clutch. Also misses at losing revs. Seems fine over about 2500 and pulls well once going. Will sit on the motorway with no problems.
I have replaced the coolant sensor.

Today I have replaced the vac pipes, fuel trap and stepped motor. The ecu was removed yesterday and with cotton wool in the map sensor put on the radiator overnight.
All back together and runs the same. Ecu allowed to run 10 minutes on idle, stepper motor indexed.

I have a Sykes pickavent reader. Plugged in and no faults.

Ran some live data. Engine warm at idle.

Engine rpm: 850-900
Idle switch: closed
P/n switch: open
Map sensor 40kpa
Coolant temp: 80degrees
Inlet air temp 28 degrees
Ambient temp: 19degrees (this was inside so about right)
Battery voltage: 13.7v
Throttle pot: 0.48v
O2 sensor switching rapidly between 1.4v and 0.1v. Switching about 3-4 times per second.

Any know if these are where they should be??

Or any more help??

[matto224]

Hi ! i also have an spi which was running badly (rough idle, stalling when coming to a stop loosing power etc), to get mine running better it took a full service new HT leads new dizzy cap and rotor , vacuum pipes, new fuel filter, new battery, you may of already done these but just thought id share what got mine running right! 

[idlethumbs]

Thankyou.
All these things were also replaced when the engine went back in unfortunately.

[xrocketengineer]

Unplug the O2 sensor and try it without. The sensor should not exceed 1 volt.

[idlethumbs]

Thanks rocket. Will give it a go tmrw.
Will it not run worse with it unplugged?

[viz139]

Check the condition of the crank sensor, may have been damaged removing and fitting clutch.

Check for air leaks on hosing.

[idlethumbs]

Crank sensor is also new. The old one got broken when I stripped the engine.
I went through the breather pipes today refitted them all and seemed ok. I put a zip tie tight round each fitting just to make sure of no leaks.

[idlethumbs]

So from lots of research I am kind of expecting the stepper to be at zero steps and the advance to be wrong

Unfortunately my ACR code reader does not show these so anyone with ACT willing to share be much appreciated.

With the new cam is it feasible that I may need to set the stepper by adjusting the screw/spring thing that pushes it back in?

[idlethumbs]

So from lots of research I am kind of expecting the stepper to be at zero steps and the advance to be wrong

Unfortunately my ACR code reader does not show these so anyone with ACT willing to share be much appreciated.

With the new cam is it feasible that I may need to set the stepper by adjusting the screw/spring thing that pushes it back in?

[Pops_Guild]

You probably have, as you seem to have done a lot of things, but have you indexed the stepper motor? 4B 4 in the Haynes. Mine, rebuild had similar symptoms until I did that but mine is all bog standard.

[xrocketengineer]

Thanks rocket. Will give it a go tmrw.
Will it not run worse with it unplugged?

It should not, but it will run somewhat richer with its default A/F ratio map. A properly functioning O2 sensor only tweaks the ratio to be stoichiometric so the catalytic converter can operate properly. However, if the sensor is bad, it will feed bad data to the ECU (too rich or too lean) and the ECU will try to adjust accordingly and really mess up how the engine runs. I had this happen on a Hyundai. The car drove terribly after warming up with no check engine light and black smoke coming out of the tailpipe. Disconnected the O2 sensor, the check engine light came on and the car ran perfectly.

O2 sensor info:

http://www.autodiagn...or-testing.html

Edited by xrocketengineer, 29 January 2018 - 03:53 PM.

[FlyingScot]

So from lots of research I am kind of expecting the stepper to be at zero steps and the advance to be wrong
Unfortunately my ACR code reader does not show these so anyone with ACT willing to share be much appreciated.
With the new cam is it feasible that I may need to set the stepper by adjusting the screw/spring thing that pushes it back in?

Don’t adjust the throttle stop - please! You need the right software pod to set and it was used for initial set up of a new stepper for example.
You will be able to see the stepper indexing when you turn the key (okay when someone else turns the key)

FS

[FlyingScot]

I would check the obvious - is the cam correctly timed in and the tappets set. The SPi is pretty forgiving but if you have the basics wrong....

FS

Edited by FlyingScot, 30 January 2018 - 09:39 PM.

[idlethumbs]

Thanks flying Scot.
Not adjusting the throttle stop until I get pod 3 for the acr that will count the steps.
Should give me some more info.
I would expect the engine to be set right as its a Keith Calver build. Im not technical enough to check timing etc and I know assumption can be the mother of all f&@£ ups but at some point I have to trust someone.
I paid for one of the best to build my engine, I expect it to be right.

[FlyingScot]

My bad missed that Keith built it; should be right.

FS