Topic

Hi all

Im hoping you can help me. Ive got myself a great 2002 MGTF which Ive had for a year now, flown through its latest MOT and is used daily. I cant get enough of it!

However, its developed and bit of a misfire lower down in the rev range. Nothing too major but as ever slowly getting worse as the weeks go on.

Any clues as to what to tackle, change and how to please?

Thanks in advance.

Check for corrosion/crap on the connections to the spark plugs. Check the plugs are OK too Often get a build up of crud under the coilpacks especially.

As above from David first but if the fault is not visible you could get an ODB bluetooth code reader (£8 ish from flea bay) and download the free app Torque and upgrade for a couple of pounds to the pro version (need an android phone) you should be able to see what cylinders are misfiring on your phone with the app as they will be recorded in the fault log.

The car has only 2 coil packs so uses 1 coil pack for cylinders 1 & 4 and the other for cylinders 2 & 3 (spark idle system) When you have determined which cylinder has the misfire swap the coil packs and leads over, If the fault transfers to the other cylinder you can isolate exactly where the fault is. It fault remains on the same cylinder you will have at least narrowed the problem down.

Brian.

Thanks gents thats most helpful. I was thinking of replacing the spark plugs and leads anyhow as Im not sure when they were last changed. My thoughts were do that having gone to the trouble of accessing the engine bay.

Is an easy job to swap the coil packs for new ones?

Markw wrote: wrote:

Thanks gents thats most helpful. I was thinking of replacing the spark plugs and leads anyhow as Im not sure when they were last changed. My thoughts were do that having gone to the trouble of accessing the engine bay.

Is an easy job to swap the coil packs for new ones?

The hardest most time consuming job is removing the engine cover, once the the cover is off; the cam box cover, coil packs, leads and plugs is a breeze.

Brian.

Yep, what they said. We had the same prob and I changed the 2 leads and the plugs. Noted exactly the crud problem that DA mentioned.

While the engine cover is off, good opportunity to check the air filter.

Is your car a V V C or 18i

Thought the same thing about changing the air filter whilst Id got access.

Its a 1.8i

Well thanks to your advice I now have a MGTF running beautifully. Turned out to be the Coil Packs. So they have been replaced, new leads and plugs with a new air filter.

Im really chuffed.

Thanks again for all the help.