Not enough 960s on this board...

Last May when we were heading to Portland our 960 had a bit of a hiccup. After filling it at one stop it started to miss. At first it seemed like a bit of a mis-fire but then it got worse and eventually was acting like it was missing on 3 of the 6 cylinders it has. Not only did it seem like it was missing on 3, it seemed like 3 consecutive. The whole car would rock back and forth. It was nasty. Apparently the were flames spitting out the tailpipe too. The flames part is relatively important as it points to an ignition problem, not a fuel problem. Anyhow, this went on for a few minutes and then went away...quite abruptly. For the next 400km it ran like a dream. However, after the next fuel stop it did exactly the same thing...and then abruptly stopped again. For entire rest of the week and the entire trip home it ran without so much as a hiccup.

Fast forward a month or two and Beth comes home one day saying the car was doing its thing again. Then again and again. I decided it was time to give something a try so I replaced all the coils and spark plugs. That cleared everything up and the ran ran flawlessly...until yesterday. It acted up for about 1/2 hour (I was driving it while Beth drove my car to Edmonton) and then quit abruptly, just like before. Again today it did it, not once, but twice.

So...some input? I've got a set of coil control modules that will go in this weekend. Anything else might cause this behaviour? How about a bad knock sensor? If the computer was seeing horrible knock would it pull enough timing out to make it start missing? It gets gradually worse. It does not start out missing on 3. What else? Cam position sensor (does it have one?)?

Andy and Jordan, could you ask some of the techs to see if they've seen this behaviour?

I'm not going to be of any use for this thread - other than to point out that "flames" coming out the rear is not the best description of what Deirdre and I saw...it is what Deirdre blurted on the radio to Dale and Beth, causing me to have a moment. It was more like the cat lit off some fuel than it was a flame show out the back. There was some black smoke, a few "sparks" then a puff of black again and the 960 was away to the races.

Are we sure this is engine related and not related to a faulty cat (note I didn't say a faulty Kat ). What if it was partially blocked/clogged or whatever happens to those things.

Techs - jump in with some sensible responses.

Given the power it has when running correctly, I really doubt the cat is plugged. It doesn't smell like a bad cat either. I don't know if anything else goes wrong with the cat. The reason I think the flames are significant is it shows the fuel is entering the cylinder but there is no spark to ignite it so it's blowing through as unburned and is ignited by a red-hot cat.

My point, rambling as always, was that it wasn't like you were shooting fire balls out the tail pipe - more sparks than flames.

Hows the wiring to the coils?

Not sure why that would cause it to drop 1, 2 then 3 cylinders and then, like someone flicked a switch, back to running on all 6. The wiring looked fine when I changed the coils although one connector was missing a clip. I may take the cover off and zip-tie it on.

Changed one of the coil drivers today...the rear one. That was a treat. My wrists don't bend that far that way

The rear coil driver was original, I think. The front coil driver is the same part number but slightly different packaging. If I had to guess, I'd say the front one was newer. Guess I'll drive it another day to see if I can make it act up again with the replacement (not new) in place. If I can't, I'll toss that old coil driver in the trash and call it good...

Good luck, hope this cures the problem

Drove it all day today and not a single hiccup. We'll call this one busted until it happens again...

Good to know ONE of our poopheaps runs, then. Mine started acting up again today. It had the old RSR in it (the one that was in it on the way back from Streetwheelers) and this is the first time it's given me trouble since. I'd like to say that a new one fixed the trouble, but for the second time the starter decided to give me trouble too, and there was a cooldown period that may have helped it too.