15 replies to this topic

[mini_mezza]

Hi all, I've had my standard SPI modified to 1293 with stage 2 head and a pretty mild cam 1:5 rockers she also has a maniflow exhaust with cat. And standard cooper ECU

The emissions are reading 6.something rather then 0.7 or what ever it should be.

My Initial thought is a sensor somewhere has gone, or the ECU is unhappy, where do I look first! I know hundreds of people have modified these engines with far more wild components than I've got in mine, and they seem to pass through MOT's fine.
Any info or experiences you've had will help.

Thanks
m_m

[Fast Ivan]

post the actual figures up

does it look like its running rich? fuel consumption high? spark plugs sooty?

are you using a lot of oil?

[mini_mezza]

Plugs are pretty sooty. Engine had about 5 miles on it since the build, so can't tell you about fuel consumption, and I bloody hope it's not using any oil after being fully rebuilt by a pro!

Will try and get figures ASAP

m_m

[Fast Ivan]

so its running rich, don't drive it until this is sorted otherwise you run the risk of bore washing your new build, which is major agro

do you have access to a code reader? this is going to prove an essential item for the injection mini owner

make sure all of the sensors are clean and secure, check the loom for damage

check all of the vacuum hoses, they need to be in perfect condition, replace if theres any doubt

[minisilverbullet]

Probably nothing to do with it being modified! 

 

Likely to be a fault with the unmodified injection system. 

 

As always with SPI's you must check all vacuum pipes. take them of and closely inspect for any holes. 

 

Next step is to get any fault codes read. 

[mini_mezza]

Thanks guys, that's certainly put my mind at ease about the motor it self. The vacuum pipes are all new, and I'm taking it to my trusty mechanic on Tuesday to work with him on it for the day. Can anyone provide a detailed description or picture of how the vacuume pipes should all connect?? Thanks
m_m

[tmsmini]

Here is a diagram

[xrocketengineer]

Make sure that you do not have any leaks in the exhaust upstream of the oxygen sensor. Any air that gets sucked in will be detected by the oxygen sensor as a lean condition and will result in the ECU making the mixture richer. You could try disconnecting the electrical connector on the oxygen sensor to see if the condition improves.  The engine will run fine in the open loop mode meaning the mixture will be adjusted using a mixture default values using the other sensors of the engine I.e. MAP, CPS, CTS, AIT and so on.

Edited by xrocketengineer, 25 March 2016 - 12:42 AM.

[mini_mezza]

Right, so we seem to be making some head way.
We have dropped the emissions quite a bit by changing the water temp sensor.
All the vacuums hoses are in good nick and flowing freely! We tested the MAP by putting a vac tool on the ECU, this allowed us to control the fuel by changing the amount of vacuum, and when this was on we obviously got the emissions down to a pass because we weren't over fuelling.
We've now narrowed it down to the AIT sensor, as that's the only one we haven't changed and we put a Volt meter in to the ECU wire block bit with the ignition on. This should have given us 5v but we were only getting 0.2v would a faulty AIT throw the emissions out significantly to fail the MOT??
I'm sure that plenty of people would suggest diagnostics, but struggling to find one near by!


Thanks
m_m

[minisilverbullet]

It may be an ECU issue!

[mini_mezza]

It may be an ECU issue!

I'd rather it wasn't! 

[FlyingScot]

Can you clarify are you saying the supply from the ECU is only 0.2V ?
MEMS produces its own internally regulated 5V for some sensors etc.

As your profile doesn't say where, have you checked the pinned thread for members who have diagnostic gear and are willing to share?

FS

[mini_mezza]

Can you clarify are you saying the supply from the ECU is only 0.2V ?
MEMS produces its own internally regulated 5V for some sensors etc.

As your profile doesn't say where, have you checked the pinned thread for members who have diagnostic gear and are willing to share?

FS

Apparently according to a bit of software my mechanic uses (some trade program) if you disconnect the loom from the ECU and stick a Volt meter in pin 16 of the loom block, it should read about 5v with an ambient temperature around the sensor, ours didn't, it read 0.2v with no significant change with an increase of temperature around the sensor.... Would you agree this renders the sensor duff or not??
I'm based near alton in Hampshire, tried contacting one guy via the thread but no response!

cheers m_m

[minisilverbullet]

Page 4 of my topic from some years ago - I had no voltage at pin 16 (IAT sensor).

 

Description of the cause from the ECU repair company - 

"This Engine ECU has been tested several times and found to be faulty. The internal power supply circuit has been overloaded and the 5 volt output rail has failed. Refurbishment is required."

 

 

http://www.theminifo...data-spi/page-4

[FlyingScot]

Page 4 of my topic from some years ago - I had no voltage at pin 16 (IAT sensor).
 
Description of the cause from the ECU repair company - 
"This Engine ECU has been tested several times and found to be faulty. The internal power supply circuit has been overloaded and the 5 volt output rail has failed. Refurbishment is required."
 
 
http://www.theminifo...data-spi/page-4

Aye sadly that's what it's pointing to.....
Is you ECU matched to an alarm module ? Or is it a non coded one?
If you post the part number I can tell if your not sure.

FS