318i spluttering and losing power

[jaxon]

Hi all,

I've had my new 318i for a couple of months now and I've been driving it fairly regularly on longish runs, not pussyfooting around but not really going much above 4.5k revs either and it's been running faultlessly.
This evening I was driving around town and residential areas at constant a 20 and 30 mph. After about an hour it started giving a couple of splutters then was fine, then it came back a little worse finally getting to the stage where I pulled in because it had lost all power and wouldn't accelerate. Basically it behaved as if it had run out of petrol yet when I pulled in it didn't stall although the idle was a tiny bit lumpy. I managed to pull off again and it seemed ok, I got to open her up a bit on some back roads on the way home and she ran absolutely fine, pulling strongly up hills, out of corners etc without a hint of spluttering.

Anyway I need the car to retake my driving test on Wednesday which will involve the same conditions as those that set it off spluttering and obviously that wouldn't look good to an examiner!
Any ideas/things I can check easily myself?

Cheers in advance

[bimanut]

Just check some of the basics.
Oil.
Air filter
Inspect condition and clean the plugs.
Clean dizzy cap & rotor arm contacts.

I used to have an E21 when i was a kid and it ran like a lump o sh** did the last two on the list and it ran good for a bit.

[jaxon]

Cheers, I'll give those a try, how do you remove/clean the dizzy cap and rotor arms?

It's 1990 model with the M40 engine btw

[bimanut]

On the black dizzy cap cover you will see three bolts,undo those take the plastic cover off then the dizzy cap will come off.
Wipe any carbon dust out.Then give the contacts a gentle rub with a bit of sand paper to remove some the pitting (dont go daft.)
The rotor arm doesnt realy need to be removed.Do the same to that and gize it a gentle rub to get any crap off.Then blow any dust out.
If you`ve got a bit of contact spray give it a dusting of spray.
Job done.

Oh and look for any cracks in cap.If there is get another one.

[jaxon]

Just been out to the car and the oil looks fine, cleaned the air filter out a bit and checked all the hoses for cracks, all was fine. I'm not used to working on the 4 pot and it has smaller plugs than my old 320i which I didn't have a tool to remove.
Now I'm no mechanic but the dizzy cap looked fucked, the contacts on the cap and rotor arm were pitted and corroded, the cap itself was broken where the bottom bolt goes into the block and that bolt had sheared off at some point and had rusted into the block.
For now I've cleaned the contacts up as best I can with a mini file and some wire wool and stuck the cap back together with impact adhesive, I'll get a new one ordered though!

Anything else I've missed checking here?