21 replies to this topic

[Diogo Tomaz]

Hello all,

 

I have a Mini MPI from 1998 (Monza Edition) and since two month i'm facing what it seems ECU problem. Full throttle

 won't reach more than 2.000 rpm as you can see on the video.

 

I already change:

• Ignition coil pack - MPI
• Spark plugs
• New plugs

The mechanic already made a reset to the ECU and nothing happen.. then, we grab a Rover ECU and made a copy and start working perfectly...! But.... the next day returned to the same problem...

 

Anyone can give some tips what exactly is?

 

Edited by Diogo Tomaz, 17 January 2015 - 06:05 PM.

[Guess-Works.com]

Had something similar after installing a new engine, would not rev, turned out I'd forgotten to connect the cam sensor.

Basically, sounds like it's going into safe mode which means a critical sensor(s) is not reading, connected or otherwise not reporting to the ECU...

 

You need to connect it to a code reader, preferably one designed to read the MEMS unit, ACR4 or T4...

 

Just listened to the vid, if it were a carb, I'd suggest fuel starvation, which may be blocked injectors, fuel pressure etc,, All this information would be available if connected to a diagnostic machine.

Edited by Guess-Works.com, 17 January 2015 - 05:19 PM.

[Diogo Tomaz]

Well the car it is in Land Rover specialist... i don't know if they have those code readers. They have a code reader that could find the first problem was the ignition coil pack. I bought one.. problem solved. But then.. the machine (code reader) didn't detect anything but the problem still maintained...

I'm a little worry with this... because he is Rover specialist.. and i really need your (forum) help to try to give some ideas.

[hennasxi]

Fuel pump or filter must be prime items to check, if its not the injectors.   If the fault went away after fiddling around the ECU, perhaps you have a wiring loom issue from a sensor?  Try fiddling around there again !!

[FlyingScot]

A Code reader will narrow down the problem which could be several issues.

One problem I have seen before is the TPS the throttle position sensor. It has 3 connections earth, signal and 5V, either when car is on using a multimeter set to volts or disconnected and set to ohms. You should see a steady change as you work the throttle.
If this is worn or faulty The MEMS ECU can't work out the amount the throttle is open.

In the absence of a code reader I would be checking this first.

FS

[Fast Ivan]

could well be sensor related but also worth checking some mechanicals as well - does the throttle body operate ok? no sticking, throttle cable moving freely. is there a restriction in the air box? (would have to be huge but worth checking), is the cat clear? anything wedged up your exhaust?

[Diogo Tomaz]

I heard something about the catalyst... and i know one guy that told that have a similar problem and was catalyst problem..

What you think?

[Fast Ivan]

I think you should take the cat off and the inspect or maybe replace with a decat

[hennasxi]

One guy had his cat internally block as it had kind of self destructed, which had the effect of blocking the exhaust, so it could well be the cat itself.  I've only heard of that once before, but it is a possibility.

[Diogo Tomaz]

Hello Guys,

 

The problem still remains...

 

We already change:

• Ignition coil pack - MPI
• Spark plugs
• New plugs
• ECU model
• Relay
• Crank sensor
• They verify the lambda sensor also

The weirdest thing is... the car sometimes is working good, then after a while (after he ges warm) 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 exausht 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... )

[FlyingScot]

To be honest the most use of the code reader is in running values not the fault codes. No fault will normally come up with the TPS u mess disconnected. Use a multimeter to validate if not code reader available other if you have a code reader loom at TPS reading as you depress accelerator.

FS

[Diogo Tomaz]

Thank you so much! Next monday i will bring the car from the workshop and i will put on my garage. My dad's friend is a specialist in car electronic.. he already has the manual of the car with all the diagrams and 1h per day he is going to work in my garage.

 

I hope that he can solve the issue and i will tell him about the throttle position and use a Multimeter.

 

What is TPS (sorry my ignorance)

 

BY THE WAY:

• We already verify the Injectors.
• Also smells a lot of gasoline that is not burned.

Edited by Diogo Tomaz, 17 April 2015 - 08:17 PM.

[FlyingScot]

Throttle Position Sensor = TPS
It's the variable resistor used to sense where the accelerator pedal position is.
FS

Edited by FlyingScot, 17 April 2015 - 07:44 PM.

[Diogo Tomaz]

Throttle Position Sensor = TPS
It's the variable resistor used to sense where the accelerator pedal position is.
FS

 

Can you tell me what is the numbers that i should have while im testing the resistor? (or can you give more details about that)

 

Regards

[FlyingScot]

A Code reader will narrow down the problem which could be several issues.
One problem I have seen before is the TPS the throttle position sensor. It has 3 connections earth, signal and 5V, either when car is on using a multimeter set to volts or disconnected and set to ohms. You should see a steady change as you work the throttle.
If this is worn or faulty The MEMS ECU can't work out the amount the throttle is open.
In the absence of a code reader I would be checking this first.
FS

Measure volts it should go something like 0.4V up to close to 5V

FS

Edited by FlyingScot, 20 April 2015 - 07:47 PM.