19 replies to this topic

[logiedurno]

Very, very strange!!!!

So it's gone from firing on 1 & 4 only to firing on 2 & 3 only? What did you change to make it do that? is it still sparking on 1 & 4 but just not firing?

I know the MPi Coil Pack produces a "wasted spark", i.e. sparks on every stroke, just wonder if there's something not right there?

I wonder if 1 & 4 are the wrong way around? Try swapping them over (you may have to do the swap at the coil pack end as I think they are different length leads?).

PS - if you look at the two pictures I posted, the one on the left is from Haynes and is correct, the one on the right is from the Pukka Rover manual and is wrong (2 & 4 are the wrong way around - should number from bottom left 1 - 2 - 3 - 4 clockwise)!!! Which way have you got your's?

I think we may have to await the "MPi Doctor's" (Sprocket) input

I really don't know why it decided to change around like that. 1 & 4 no longer sparking. I have the leads on the correct way round (as per haynes) but have tried swopping them about in various ways and configurations with no success. Trying it the Rover config produced a real backfire!
It was when cylinders 2 & 3 weren't firing that I decided to check the compressions as I thought the head gasket could have gone between Nos. 2 & 3 but as I said, all the compressions were fine.

I noticed from the wiring diagram that there is an in-line 1 amp fuse to the rev counter somewhere but I've taken the dash off and removed and even dismantled the rev counter but I cannot see it.

Probably grasping at straws now - but I know the rev counter is tied into the coil circuit somehow and I thought if the rev counter isn't working perhaps some switching signal to the ECU isn't getting through?

Someone with a better understanding of the auotelectrics might be able to put me right.

Edited by logiedurno, 31 May 2009 - 10:03 AM.

[nicksuth]

I don't think it's a 1 Amp Fuse, I think it's just indicating the "load" it takes? All of the instruments are on fuse A4 in the Passenger Compartment Fuse Box.

Have you checked the MEMS Control Unit and the Engine Bay Fuses? Might be worth just removing and cleaning up contacts then replace/re-seat?

I'm not sure if you can replace the individual Relays in the MEMS? Might be a case of a new unit (or borrow one to test?)

Also, have you checked the multi-plug in the bottom of the Coil Pack, you may have a damged/cracked wire or dirty connector. The reason I mention this is I did an oil and filter change on mine yesterday and I didn't realise how tight the filter removal would be!!! Ended up taking the coil pack and oil pressure switch connector off so I could wiggle it out, noticed that there's not much free movement with the wires and i could see it could be quite easy to stretch/damage them???

Good Luck - Bloody MPi's

PS - I've PM'd Sprocket to have a look at this thread but I think he must be away as not seen him on for a while???

[logiedurno]

I don't think it's a 1 Amp Fuse, I think it's just indicating the "load" it takes? All of the instruments are on fuse A4 in the Passenger Compartment Fuse Box.

Have you checked the MEMS Control Unit and the Engine Bay Fuses? Might be worth just removing and cleaning up contacts then replace/re-seat?

I'm not sure if you can replace the individual Relays in the MEMS? Might be a case of a new unit (or borrow one to test?)

Also, have you checked the multi-plug in the bottom of the Coil Pack, you may have a damged/cracked wire or dirty connector. The reason I mention this is I did an oil and filter change on mine yesterday and I didn't realise how tight the filter removal would be!!! Ended up taking the coil pack and oil pressure switch connector off so I could wiggle it out, noticed that there's not much free movement with the wires and i could see it could be quite easy to stretch/damage them???

Good Luck - Bloody MPi's

PS - I've PM'd Sprocket to have a look at this thread but I think he must be away as not seen him on for a while???

I've checked all the fuses, enginge bay and relays etc for damage or corrosion - all been taken out and ccontacts cleaned etc. and meter tested for continuity - they all seem fine.

The coil pack multi plug has been on and off loads of times (as you can imagine) but the connectors appear to be quite sound and I have checked for continuity all the way back to the appropriate connector on the ecu plug and that again seems fine.

Quite agree tho.. bloody MPi's

[logiedurno]

Hopefully final update on this one...

Having checked and rechecked all the previously mentioned components I came to the conclusion that the most likely culprit was still the coil pack.

Now remember, I had tried 2 secondhand units that were known to be working from other vehicles with no joy so I then went and bought a brand new Rover coil pack unit (about 75 quid) and was still only firing on two cylinders, albeit now switched from cylinders 1 and 4 to numbers 2 and 3.

So today, (out of sheer desperation and before chucking in the towel and towing the car to an autoelectrician specialist) I went to local Partco and bought a another ignition coil (46 quid this time)

Plugged it in and hey presto, now running on all cylinders. Only thing now though is the rev counter still isn't working and I'm wondering if the electronics in it got knackered when the original coil pack blew..

Anyhow, I'm now a mix of very relieved and decidedly peed off that I have wasted so much time, money and effort and following a phone call to Rover parts it would appear that it is unlikely I will get a refund on their coil pack as they are suspicious that it may have been damaged by me! bloody cheek!

Just have to find a working rev counter now - here we go again.....

Thanks to NickSuth by the way for his helpful support.

[nicksuth]

Hey, no problem. just happy to hear you have got it sorted. I would not have thought a brand new Rover coil pack would have been "duff", I'd stick at em for your money back or at least a credit note for some future parts?

Bloody MPi's, don't you just love em >