Help explain what has been modified please

[Nige]

Checking the base timing and ensuring it is at the recommended 16 deg BTDC is a must. Although in theory it shouldn't drift from this and it's not a service check the fact is it does move and will in in all probability be out. Setting it correctly may resolve your problems, if it doesn't then you'll know it's right and you'll have eliminated that as a potential cause and it won't have cost you anything (if you do it your self). I would do this before I change anything else.

[saska]

Does the timing seem OK after the initial 5 mins?

No. Variation is too great 10-23° should be 5-6° of variation (15-20° BTDC)

Could base timing be an issue or does it sound like coil packs?

I'd agree with Nige that base timing is v. important. Check it first.
While checking base timing see if you get a solid strobe or a fuzzy strobe.
If you get a fuzzy strobe then either the CAS has play in it or the cambelt is too loose allowing the CAS to flutter.
If you get a solid strobe while timing then neither of the above is your problem and you need to check for other things.
In the first instance I'd disconnect the battery to reset any ECU learning.
After that the way I'd then approach this is to order things as either:
1. Easy & costs nothing.
2. Easy & fairly cheap
3. Hard & costs nothing
3. Hard but fairly cheap
4. Easy but not cheap
5. Hard & expensive

So unplugging/checking/replugging every electrical connector going to the engine is easy & costs nothing -- including the injectors (mind the clips) and the CAS (1 to right & 1 below from airbox side) as well as the connectors into the coil pack base plate. I'd also check the IAC connector closely.
Remember the car is >16 years old so these connectors may have corrosion.
After that I'd probably change the HES in the CAS as it's cheap and fairly easy.
I'd tend to think the coilpacks are OK since they fire well at 5000 RPM
If I had to guess then I'd think IAC is failing or dirty & giving weird idle levels that the ECU is trying to compensate for.
See section EMK4-9 Page 105 of Engine Management Manual V6

[OZZY]

Thanks for all of your advice, thats given me quite a few good pointers to go and explore, these engines are a little more complicated than I first thought!

Been busy sorting out the alarm, so not had a chance to look at the base timing yet. Before that I'll try disconnecting the battery so the ECU can aquire fresh settings, cant help feeling I've disturbed something taking out the BBR kit.

[saska]

cant help feeling I've disturbed something taking out the BBR kit.

Did you have the lumpy running from cold before you removed the BBR kit ?
Also have you still got the original ElanScan before you removed the BBR ?

[OZZY]

No lumpy running from cold with the BBR kit installed.

When I took it off I had problems with the idling straight away but put this down to the appalling rain and the fact that I'd left my bonnet open, mid storm.

The day before Owen (another member) took a scan with his computer and kept the log with the BBR kit , I asked him to email it or post it up but no joy as yet, I think he's away on holiday right now. I think he said that the CAS was showing some wear, but didn't need replacing, so he may have seen the same timing data you are highlighting.

[OZZY]

Cleaned the IAC, disconnected the battery for a few minutes and the lumpy start up has improved significantly, probably gone, timing I suspect is still an issue.

Tried checking the base timing only to discover that my strobe was broken!

I think my problems now are probably the HALL sensor, I might have a very small air leak somewhere under the bulkhead on the drivers side, I guess a length of tube will be best to check with.

Hot starting still an issue, but talking to previous owners it always has been, will keep you posted.