Maserati V7 isn't what I'd hoped for ....

[Snowflakes]

So, the same day I booked the car in for a service at DL (Paul may bring it to you sooner now!) I get the orange engine light come on, car vibrations are up (especially sat still), & totally down on power so can only guess we're running a cylinder down. The dealer I bought her from (just over a year ago) needed to replace a ignition coil so guess another could have gone, or there's an issue with one of the spark plugs ..... without the manual removal/replace of each ignition coil & spark plug, any bright idea's how to determine which of the eight isn't playing ball?!

I'm a decent/competent, albeit not massively experienced, home mechanic but lacking any specialist tools. ....

SF

 

[conaero]

Use an obd code reader. Bonnet up, looking at the engine, cylinders are numbered:

Bulkhead
4 5
3 6
2 7
1 8
Front

 

[davy83]

Hi SF the ODBII reader will only help if one of them fails, but they can be flakey, and this is harder to nail down. As far as I know you can try removing the connector from each cylinder in turn (one at a time) and see if the engine idle becomes less rough when any of them are removed. If the engine runs smoother then replace the coil pack. I replaced 3 or four of mine and the engine did seem better. Sorry its a bit subjective and the guy who i got this from had much experience under his belt and so knew exactly what he was looking for.

 

[dunnah01]

I use one of these Coil on Plug testers

http://www.ebay.co.uk/itm/ADD750-CO...iagnostic_Tools_Equipment&hash=item3a7e9c3fd3

I managed to get mine for £16 off fleebay - the advantage is very little dismantling required and 100% accurate.

 

[cobratwin]

sounds fairly similar to a MAF breaking down too easy to check just disconnect the MAF idle will be bad but power should be back once moving.
if you have a auto it will also be hard to start and maintain the idle but try and get moving asap and you should be fine to test the power.

 

[Snowflakes]

Thanks for the advice chaps - heading home early to try the DIY removal of electrical connector/Coil Pack one cylinder at a time! May go for one the plug testers if its not conclusive & get it done later in the week!

Will keep you posted!

SF

 

[Elliott653]

Use an obd code reader. Bonnet up, looking at the engine, cylinders are numbered:

Bulkhead
4 5
3 6
2 7
1 8
Front

That's interesting. The front right ignition coil (no8 on your list) went on my 2006 QP yesterday. When the AA man checked the engine through the data port, the code indicated that that coil was number 5.

He removed number six which vibrated to show me how a coil should operate. Then he took out number 5 which was dead. Are the engine layouts the same in 42s and QPs?

 

[Snowflakes]

He removed number six which vibrated to show me how a coil should operate.

Hi Elliott - what do you mean vibrated to show you how it worked?! Can you describe that?! May help my diagnosis!!

So - disconnected each injector electrical connector (easier to disconnect than coil packs) in turn & surprise, surprise it was the first I tried. No change (minimal compared to the others) in engine tone or vibration so whittled it down to No.1.

Ran out of light (& warmth) so weds night will be a swap of no.1 & no.2 (or any other suggestions or why?!) coil packs & see if the problem moves with it!

Thanks so far & more to come!!

SF

 

[Elliott653]

Sure. With the engine off, he removed one of the coils that hadn't shown a fault but left it connected to the wiring loom and asked me to start the engine. I did so and he showed me that the removed coil actually shook in his hand - it's extremely hot having been driven down from Luton to London. He replaced that and next removed the dead No5 coil and asked me to start the car. This time the coil didn't shake. This, he said was proof that the coil was dead.

 

[cobratwin]

Anyone have a part number of the coil packs? ive about 20 here that look identical to the ones i can see on ebay but no part number.

 

[conaero]

That's interesting. The front right ignition coil (no8 on your list) went on my 2006 QP yesterday. When the AA man checked the engine through the data port, the code indicated that that coil was number 5.

He removed number six which vibrated to show me how a coil should operate. Then he took out number 5 which was dead. Are the engine layouts the same in 42s and QPs?

Mike told me this, ill check I got this right and come back to you.

 

[Snowflakes]

All fixed woohoo! Why don't I ever learn to carry out a proper diagnosis!? So a new coil pack (p/n 188504 Cobratwin although there's two part number depending on length of cable to connector) arrived last weekend finally from a special order from Italy & no surprise, no fix. So finally carried our a little diagnosis by earthing the live spark plug against the crank case with the engine running (against the hex of the spark plug, not the end!) & no spark from No.1 spark regardless of which coil pack I put it in so dodgy spark plug - simples! £10 later & the car's working a treat again! Shame as it's now with Dick Lovett for a major so won't get to enjoy it for a few more weeks! Looking forward to getting it back on the 13th at the SM event though! See you all there?!?

SF