Ok, i will check the idle also.

Thank you!

This is the idle air controller

There is a hose that attached to it, check that. Two O rings, be very careful with those.

Also it is possible that the valve is not attached to the inlet manifold properly.

The steps of the stepper motor is not a fault, it is a value which would indicate other issues. And yes this normally would only impact idle.

Terry

Well in the workshop they also checked the butterfly and they told me that was ok.. i will check again that.

About the idle i don't think they check that because, i never had a problem with that, so i don't believe they make any change.

Regarding to the code reader, i need to ask them, but they inform me that was everything ok with that, no error returned.

Diogo

The common problem is that when warmed up the butterfly in the throttle body will stick and not return completely to the idle position, letting more air in.

In your situation it sounds like it could be sticking preventing it from opening. I don't think this is case as the idle would then stay high as well.

Just make sure it moves freely through out its range.

Has anyone tried to adjust the idle with out using the proper tool?

Did the code reader give a readout on the stepper motor and how many steps are available to it?

Terry

Hello Tmsmith,

• Fuel injectors - adequate supply and good pattern? YES, they test it on a specialized company and its working perfectly
• Spark plugs - good spark at the right time?  Yes, i changed two times the COIL and also the relay.
• Air supply - no leaks? That a point that i need to check.

About the butterfly i need to check what is the behaviour between a good one and mine.

Thank you so much for all your help, and also the everyone.

Typically this is the throttle body that causes problems when warped. Usually it is the opposite, the RPMs will not settle down at stop and stick abovre 1500 or so.

I imagine the inverse could happen as well, stick and not open beyond a certain point. The issue can be checked by moving the butterfly in the throttle body when warm and see if and where it sticks. 

Burlen sells a metal replacement, but usually light sanding can "fix" the problem unless it is severe.

Have all the basics been checked:

• Fuel injectors - adequate supply and good pattern?
• Spark plugs - good spark at the right time?
• Air supply - no leaks?

I know you are working on some of these checks, but sometimes it malkes sense to start with the basics first.

Terry

Hi! Can you tell me which part you are talking about? Since i don't know much about mechanic i would appreciate your help!

Regards

I've seen some other posts about the MPI cars having a problem with the intake warping and causing air leaks. If memory is correct, they were plastic and would run ok until the car got up to temp. then the problems started.

Hello everyone,

I will check the filter this week.
In the workshop they use MEMS 2J and they test the cam sensor. They replace and its the same behaviour...

I would check those two parts (idle air valve and purge valve).

Thank you guys!

I would also replace the fuel filter as you may not know when it was last replaced, if ever.

Was the code reader specific to the Rover MEMS 2J that the later Minis used?

If so it would have tested the cam sensor as well. If it is intermittent all it will tell you is that there is no signal for the cam and crank. If people have not used the wire ties that come with a stock installation the wandering cables can chafe and rub insulation off.

The idle air valve could be an issue if it is stuck. Also the purge valve could contribute to a "manifold leak" like condition if it has failed open.

Also check the grounds.

I second the vacuum connectors

You  might also check to see all the vacuum hoses are in place and not cracked. That may prevent what you are experiencing. A loose one on my SPI resulted in what you described.

That sounds exactly like a blocked cat. I know you say they have checked but I would have them check again. Otherwise pull out the O2 (lambda) sensor and try reving so the gasses can escape through that hole in front of the cat.

cheers

Barri

Hello all,

I have a Mini MPI from 1998 (Monza Edition) and since five month i facing what it seams electric problem. Full throttle won't reach more than 2.000 rpm as you can see on the video.

https://www.youtube.com/watch?v=wOjf1c_Wjl8

I already change:
- Ignition coil pack - MPI
- Spark plugs
- New plugs
- Relay
- ECU with FOB
- Crank sensor
- They verify the lambda sensor also
- They verify the injectors and they are good (went to a specialist)

The weirdest thing is... the car sometimes is working good, then after a while (after he gets warm and smells a lot of gasoline) the problem appears... Do you think that is anything mechanic? What more things that i can see?


They also check the cat, and also check the exhaust and they are functional. The code reader didn't detect anything...

About the throttle position sensor, if its with any error the code reader will detect that?

(I'm so tired of this problem... and the worst thing is.. im in Portugal and no one can really understands this MPI engine... )