355 'limp mode' musings

I disconnected the 4-port plugs from both cat ECUs last night and started it, let it run for a few minutes then shut it down. It sounded the same (eg awful) and I had two SDLs on the dash. Plugged all back in, left overnight with battery off.

Still running badly this morning but no SDLs with all reconnected again.

 

Some progress. Unplugging the connector from the o/s coil pack keeps the engine running the same as before, eg rough and horrible. Unplug the connector from the n/s coil pack and it dies.

Perhaps one of my new coil packs is dead already...

 

Switching for known good coil packs didn't help.

How can I check power is reaching the pack? Stick a multimeter into the connector plug while it's disconnected and the car is running? Which pin should be 12V?

edit: Middle pin. Turns out it does have power. Next!

 

Sorry for my silence here, I haven't managed to electrocute myself on a coil or anything, I've just been busy.

Tonight I had a good old session with a multimeter on the relays in the footwell fuse box and I think I've found that the RH fuel pump relay is knackered. It's kind of late and I don't want to annoy the neighbours by swapping relays around and firing it up so I don't know for sure but it certainly looks suspect.

Another stupid question: Does 'RH' refer to the side of the engine bay as you stand behind the car?

I've got some new relays on order so hopefully that'll fix it and we can close off another "help my 355 has a problem which might be a massively expensive engine rebuild" discussion with a cheap fix.

For info (and I've done quite a bit of research about compatible relays in the last few days), my 0 332 014 140 Bosch relays are the 'Made in Spain' metal things. Not the supposedly original black plastic German ones. Not sure if that's of interest to anyone... Maybe they were all replaced at some point. Whatever, thought I'd mention it.
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Multimeters don't lie! Who would have thought a little relay could bring so much joy.

RH fuel pump relay was obviously shot. Stuck a new one in and it came up on 8 right away.

Of course now I seem to have a bloody suspension warning light on! If it's not one thing it's another... Hopefully I've just knocked something.
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Apparently the suspension warning will be tripped if you start the engine a few times without then moving the car. Which is exactly what I'd done trying to figure out the 'running on 4' conundrum. So it went off before I'd even driven the car out of my garage.

Anyway, a happy ending to this thread*; I've done about 130 miles of mixed driving, from crawling through central London traffic to a bit of a twisty road blast with motorways in between and it's been flawless. I'm sure it's running a lot smoother with the new coil packs and relays but that's probably psychosomatic...

*Until I lose the RH bank again next weekend anyway