24 replies to this topic

[swiss al]

i bought my 98 mpi a year ago as soon as i got the car i needed to put new exhaust on so bought a lcb maniflow which i wish i never got but hey .I also put a k&n on the car run fine untill i drove to france on the journey it stalled a couple of times when i stoped at tolls but then started up again straight away ever since then it hase never idled right just fells lumpey put a new air flow sensor on i think if that is the green one that goes in the inlet manifold .The car also will not drive along now a low revs with out splutering any idea and if anyone has tell me which sensor is which thanks.The maniflow minifold is also a problem because it always knocks and have now had to take cat of because the manifold was making it hit the body . Thanks

[scoops]

maby the manifold is not sealed?

[swiss al]

i have had the manifold on and off about 10 times since this prob started and it never gets better but thanks

[nev_payne]

You sure you bought the right LCB? One with the knuckle joint section? I would revert back to standard air box and see if that helps the idle, also reset the throttle body (very easy to do) on key ignition 2...what does it idle at once warm? 800rpm?

[swiss al]

sorry do not know what you mean by nuckle joint and i bought it from the maniflow people at london to brighton and they said it was the right one i did have anouther one that i bought from minispeed before and that was the exact same and it idles at about 800 when warm . how do you reset throttle body thanks

Edited by swiss al, 04 November 2007 - 08:40 PM.

[redhotmini]

does the manifold have a flexible joint between the cat flange and the Y piece (it will be the pipe that runs alongside the gear linkage rods) if it doesnt then that will need to be changed for one that does have a flexible joint, or a knuckle joint. all it does is allow the engine to move while keeping the rest of the exhaust relatively still. Check the engine steady bushes and engine mounts by grabbing hold of the rocker box and try to move the engine back and forth. If it moves then replace the engine steady bushes, there is one steady bar on the left hand side above the clutch, and one on the gearbox. excess engine movement will cause the knocking. As for resetting the throttle position sensor, do a search as its been covered many times before, or get a haynes manual as its described quite well in there.

[swiss al]

thanks for info yes did have the pipe with the knuckle joint but made no difference cat was pushed up hard to body work also had already done new engine steadys this engine moves about the least of the 50 or so minis i have owened. I have been to see mat at hyperformance in stains and he has said it might be the fuel pump because as i was telling him i mentioned that the car does run fine when you first start up cold as if the choke was on does this make sense to anyone ,also i have got about 6 haynes manuals kicking about but they all only go up to 96 so mpi is not covered and i hate having to get anouther one but thanks for help from anyone. The car has not got any worse since it first started the problem but it has got to the stage now that i enjoy driving my g reg mayfair more and that is not why i bought this mpi

Edited by swiss al, 05 November 2007 - 05:01 PM.

[Sprocket]

Could be a few things.

Most obvious if this problem has slowley got worse rather than just appearing, is the fuel filter. Change the fuel filter.

Other issues could be the wrong type of plugs causing the coil and the FETs in the ECU to overheat. NGK BPR6ES are the ones to use.

The cam sensor can cause all sorts of severe poor running if it starts or runs at all.

If the clutch has been changed and the problem appeared at this time, its not out the question that the wrong clutch has been fitted.

Ensure that the ECU ground wires are in good condition and free of any resistance to the battery, this can be very bad resulting in the ECu smoking itself.

Oh and on these later cars its more and more apparent that faulty wiring on the fuel pump/ inertia switch circuit is often to blame


These are a few areas for you to look at to start with.

[swiss al]

hi i am back with more news i have changed spark plugs about 6 months ago and they are the ngk ones i also changed the fuel filter at the same time neither of those helped with the problem ths weekend i have now changed the injection inlet manifold with all sensors on it i also changed the water temp sensor in the thermostate housing i also changed the lambda sensor none of this has helped I have also cleaned up the conection box under the water expansion tank and the earth there but neither were dirty and did no good either.

I will try to explain what acctually is wrong with the car it has a poor idle it kinder sounds like it is runing rich as if the choke was out when the car is warm.It idels at about 900 so that is alright and when it is first cold it ideals at about 1000 and sounds better.

When driving the car it is fine when accelerating but if you try to go along at constant speed in any gear if you are under 2000 revs it kangaroos as soon as you accelerate it is fine again or if you go over 2000 revs it is fine again .
please try to help i am just about out of money now as well as pacience.

P.S have had the car at rover and found no faults on computer

Edited by swiss al, 21 November 2007 - 06:33 PM.

[elvisthepizzaman]

have you checked your motor mounts? part of the "kangrooing" is the fuel system implementing its fuel cutoff system to increase efficiency. worn motormounts will amplify this procedure into what you feel.

Did you clean your Idle control valve throughly when you changed the manifold?

[minicooper1.3i]

have you checked your motor mounts? part of the "kangrooing" is the fuel system implementing its fuel cutoff system to increase efficiency. worn motormounts will amplify this procedure into what you feel.

Did you clean your Idle control valve throughly when you changed the manifold?

This may sound like an obvious thing to check, but my 98 MPi would kangaroo at low speed, crawling through traffic for instance, around 1500 rpm in any gear. The solution was to seal up a leak in the exhaust between the CAT and back box. I knew it was leaking from there as it had dropped about 3 inches at the join. Anyway, sealing and clamping it up, fixed the kangaroo juice and stopped the idel going haywire. It would sometimes get stuck idling at 1550rpm when i'd been stop/starting through traffic.

So, suggest you block the tail pipe with a bit of rag and have a good look and listen to the whole exhause system, not just the manifold.

Hope that helps!

[rossikey]

have you checked your motor mounts? part of the "kangrooing" is the fuel system implementing its fuel cutoff system to increase efficiency. worn motormounts will amplify this procedure into what you feel.

Did you clean your Idle control valve throughly when you changed the manifold?

This may sound like an obvious thing to check, but my 98 MPi would kangaroo at low speed, crawling through traffic for instance, around 1500 rpm in any gear. The solution was to seal up a leak in the exhaust between the CAT and back box. I knew it was leaking from there as it had dropped about 3 inches at the join. Anyway, sealing and clamping it up, fixed the kangaroo juice and stopped the idel going haywire. It would sometimes get stuck idling at 1550rpm when i'd been stop/starting through traffic.

So, suggest you block the tail pipe with a bit of rag and have a good look and listen to the whole exhause system, not just the manifold.

Hope that helps!

I also have the same issue with my Paul Smith. I was thinking it was the Lamba sensor as it seems if it running rich. I'm not aware of any leaks on the exhaust system but will have a look to see if it that causing my problem. Will let you know what I find.

[swiss al]

hello again i have noticed what i think is a leak on the exhaust it kinder back fires when slowing down but only when the car is cold i have taken the exhaust off again and gumed it up lots but still does the same thing it has done since i first put the lcb type manifold on but when i put a rag up the back there is no holes. Just to say again i have had the problem with the car running bad before i put the lcb type manifold on i have tryed two different makes of lcb manifold and they have the exact same problems will try and put new plugs and filter in on sat seeing they are the cheapest thing i can do but i did change them a year ago so hey

[nev_payne]

the back firing isnt back firing at all... its over run. Happens to mine almost every single day I've started it, and its coming up for 2 years now. Ususally its a sign that your running a tad too rich, or theres a bugger load of moisture in the exhaust system.

Just ignore it - its great for waking up the neighbours and scaring the birds.