m40 starting and running issues

[Jona1971]

Hi,

my friend is having trouble with his M40 1.8i and is bringing it over at the weekend so we can have a good look at it.

1. trouble starting
2. idles a bit rough
3. struggles after 40-50mph

any ideas where to start looking?

Thanks chaps

[Brianmoooore]

First thing to check is the colour of the spark plug tips, to get an idea of the fuel mixture strength.
Depending on the results, an air leak hunt on the inlet plumbing (big convoluted hose) may be in order, but, if the problem developed slowly, a worn camshaft fits the symptoms.

[Jona1971]

Thanks Brian,
I'll try that...

[Jona1971]

He says that at about 50mph the car doesn't want to rev any higher, feels like it's labouring and trying to get up a big hill - then it snaps out of it and drives normal.

[Brianmoooore]

He says that at about 50mph the car doesn't want to rev any higher, feels like it's labouring and trying to get up a big hill - then it snaps out of it and drives normal.

Problems with HT ignition components (distributor cap, rotor arm, plugs and (unlikely) leads can give a 'traction control' effect on an M40.

[Yeti]

if it doesn't go above 5kish,taps like mad it might be the camshaft wear, its very common on these M40 engines. (i have changed several camshafts,rockers and tappets because of this wear)

also check piping for the inlet etc as these perish with age (i have a m40 that i had to do that)

also clean the ICV as they are known to clog up( i left that soaking in brake cleaner over night, that was a year ago with no further issue yet lol )

i presume you mean vanity ? ill be there if your not sure or need help

[Yeti]

also dont be surprised if the injectors need a clean this day and age they will be needing a refresh (again i have had to get them serviced)