I am on a long trip from Singapore to Bangkok in my MCS and have been experiencing engine stumbling but only on full throttle (perhaps not engine stumbling, it feels like the feed of fuel to the engine is being disrupted when on full throttle - is this pinging?). If I am on partial throttle though, acceleration seems to be smooth as usual.

I have had a garage here in Bangkok clean my spark plugs and have also put a fuel injector cleaner in a full tank today, but I am still experiencing this issue. I have been up and down quite a few times and the engine management has not seemed to have any real issues with the differences in fuel in Singapore, Malaysia and Bangkok (although power differences are apparent)

Also, I notice that at idle that the revs are at 1000rpm instead of 900rpm. The engine was vibrating excessively also at a red light, though at the next red light, it was fine again.

Anyone have any ideas on what might be the issue? Much appreciated in advance. Have scanned quite a few pages in this section of the forum but no joy.....

Cheers

 

no codes? could be anything. you gotta find if it;s air,fuel,or spark trouble. do you have an aftermarket coil pack? i ran a deamon and it grenaded .

 

ASC/DSC on?

The rough idle is common on USA-spec cars after the emission recall for excessive gas tank emissions here, but you probably don't have a USA-spec car. Seems like MINI may have fixed the emissions problem by opening a huge vacuum leak from the tank

Aftermarket software seems to minimize the problem but I'm still hoping someone posts a DIY for a restrictor in the gas tank vacuum line.

 

Sent the car into a MINI specialist here in Bangkok this morning.

The issue is different to ASC/DSC intervening on hard acceleration.

There just does not seem to be a smooth feed to the engine of fuel, causing spluttering of the engine during acceleration due to intermittent injection of fuel.

I have had rough idling previously which is usually resolved by blipping the throttle. However, the rough idling seems to be more pronounced with the engine vibrating quite violently. This does not happen at every traffic light or stop however but I am definitely concerned.

I haven't had these issue in the 35,000km I have driven the car, on road and on track. Many Thanks to Herbie Hind and BFG9000 for all of their suggestions as to what may be causing this issue - spark plugs, air, fuel, sensors, vacuum leaks from the tank, which I have passed onto the garage owner. I hope he and his team can resolve it!

If anyone else might care to chime in, I would be appreciative!

Cheers

 

Sounds like water may be in the gas tank. I don't think MINIs have a tank drain, so the only thing to do if you have significant water is to pull the tank and rinse it out with fresh gas.

One test is to pull the gas filter off and drain it and flush it into a glass vessel and look for water... it will be a layer of lighter liquid on the bottom. If you have significant water, adding little bottles of 'wonder juice' to the tank won't absorb it enough.

If you can snake a flexible hose down to the bottom of one of the tanks (driver's side) and pump out all you can, maybe you can see if there is water.

Disconnect the fuel line and let the MINI pump some of it out into a clear container.

I'd rule out water before I spent a lot of money in other areas.

YD

 

YD,

That may potentially be it. It first occurred in Malaysia with a certain brand of fuel. I then pumped with another brand and there were no issues. When I topped up again with that earlier certain brand, the issue occurred again. Will check first thing tomorrow. In the meantime, the garage is thinking that it may be a defective fuel pump.

Much appreciated.

 

What kind of potential damage could water in the gas tank have on fuel lines, engine components, etc.?

 

Not much if you get it out soon. Be sure to change your fuel filter if it turns out to be water. Dose it with some Techron or equiv gas treatment for a while to get the last bit of water if that is what you have.

YD

 

Dudes, thanks for all the feedback. Turned out to be a simple matter of spark plugs, where I was literally firing on 3 cylinders for about 1500 kms. The car still got me up from half way up Malaysia and into Bangkok in Thailand. Have changed to NGK Iridiums and problem solved!

Cheers