So, another fault rears its head.....

[fesuvious]

It had to be; I get the boost perfect, and now....

Heading down the M40 yesterday I felt the car 'cough' steady throttle with some boost on, she coughed. Over the next hour or so she coughed (lightly) a couple more times.

Into services, nothing obvious, Oil perfect, no temp issues, so on we go

Pull off, and its the same as when I had moisture build up in the dizzy cap of a V8 I Used to have.. accelerating, but spluttering

Then, it clears. On the motorway, a little hesitant, but boost unaffected. Then, 56mph, steady throttle, no boost, a BIG cough, and then, fine again.

Its intermittent,

Do these run coil packs? Could it be breaking down? Is this an 'issue' anyone has had before? I haven't been able to work on her today so haven't looked. Will do tomorrow night though.

Help?!

[andydclements]

Yes, you have two coil packs on 4 pots. They do sometimes break down. They are bolted to the plate (which is not just a mounting plate) just under the air filter area attached to the chassis. I replaced mine with MSD ones as they are a lot cheaper but are supposedly better (hard to compare new MSD ones against known bad GM ones).

Before you look at swapping them out, check the terminals that the leads secure on are in good condition, the terminals from the plate are in good condition and that your plug leads are not at fault.

[fesuvious]

I don't suppose you have a part/model number for those MSD units do you?

[andydclements]

MSD 8224 blaster (I found it because I could remember "blaster")

[fesuvious]

Hi Jonathan (can't work out the messaging system on here !)

I'm working on the theory that an aftermarket coil pack is more than likely better constructed than the Lotus one simply due to the fact that whatever Lotus part I purchase will have been sat on a shelf for a while, plus it is a very old design. 

I certainly do not expect any performance increase. Just working on the theory that any degradation in the quality of the materials used will be less.

Am wondering if I should change the leads first (and plugs), and then, if the problem persists go for the coil packs. No particular reason, just start with the easiest!

Matty's did say they had serviced it, but I am wondering if that actually went further than oil and filter!!!!! Given the issues that were with the car I am unlikely to trust the thoroughness of their work!

[sailorbob]

There is nothing wrong with using the GM coil packs, their reliability is no worse than most out there.

As you have said, start with the easiest things first, check the plugs are new and measure the resistance of the ignition wires.

[tinywillyuk]

I'd go leads first as suggested - mine did exactly this and new leads cured it.

That said, if you want, I have a known good spare coil pack that I could loan you to test the theory.

[mr.oogieboogie]

the bottom bolts on teh coil pack earth them, 5.5mm socket easier to get to if in the air, but

you can get to them from the boot. when i replaced them i found that water had corroded away the wire inside. also worth adding another earth