So,

 

Decided to change the spark plugs and also do a compression test at the same time.

 

Plugs have been in there for 6 years or so, wanted to freshen them up.

 

Compression test I wanted to do as I plan future power upgrades, and wanted to check the condition of the engine.

 

Initially all went ok except for the coil pack wiring connectors being very brittle, going to change them as they were already missing bits before I touched them.

 

Balance bar off no problems, plugs all out easy.

 

Compression test, all cylinders hovering around the 165 mark so pretty good for a 20 year old block.

 

New plugs are BKR7E-IX, I didn't regap them (they came pre-gapped at 0.8mm, standard plugs were 1.1mm) and I think this is where I may have come unstuck though not 100% on that.

 

Put new plugs in, coil packs all on, balance bar back on, started car, seemed fine, gave it a rev then let it tick over, nothing seemed amiss.

 

Then realised I hadn't put on of the bolts for the coil pack which was under the balance bar on the passenger side.

 

So took the balance bar back off, then went to put the bolt in, dropped it, and it's now nestling somewhere in the engine bay.

 

So thought ok will just fire it back together again minus the bolt, coil pack seemed solid enough.

 

Next time I start the car it is noticeably running different, getting dark so thought I better just st5ick car back in the garage then have another look tomorrow.

 

Trying to get the car to the garage was awkward, sounded like a Scooby, and wasn't running well at all.

 

So, I'm not sure if I have made an error when I removed the last coil pack and balance bar to put the bolt in, or whether the spark plug gap has started causing a problem.

 

Can any you guys offer me some advice on what to check for tomorrow?

 

Feeling slightly nervous, don't want wreck my engine!

Is your Zed running standard boost?

 

Did you check all the balance bar O-rings were present before bolting the balance bar back down?

you didn't drop bolt in balance bar hole?

It's running a bar of boost, o-rings where all still present, I'm hoping maybe one is sitting a little off.

 

I didn't drop a bolt in the actual engine, it was in the engine bay.

Any other ideas guys?

If the o rings are seated right and that coil pack is definitely ok then I can only think of you may have disturbed a connection or hose or pulled a cable loose. 0.8mm sounds right for a bar of boost and it ran right the first time you started so I'm out of ideas mate

I wonder if you've created a problem with that last coilpack? Try unplugging it while engine is running to see if anything changes. If no change then something is amiss with that pack. Also try all the other coilpack one by one, see if any of them don't affect the idle. As above if the idle doesn't change then you have a dodgy coilpack.

Sounds like its mis-firing rather than an air leak(balance bar o-ring missing or the bar not seats right).

 

I think the problems with the coil pack at the back. Might be the plug not on fully or something

Quite possible to disturb the injector connections when moving the balancer bar.

Jeff.

So once it cooled down I had another go.

 

Took everything back off, plugs out, checked the gap on the plugs, most of them where 0.65, so increased that a bit.

 

Stuck it all back together, same issue.

 

After much messing around and swapping things it looks like I will need some new coil pack wiring connectors, they are all in a mess and don't seem to sit tight enough as they are all missing pieces.

 

Did get the car running ok, but connectors definitely suspect.