2 group cold start

[terryo]

i am struggling to get my race 4AG to start properly from cold

a quick squirt of aero-start and its fabulous, but left to its own devices it simply will not start from cold, unless its got 100% fresh plugs. this has been progressively getting worse over a period of some years

once its hot and been used in a race, restarting is still no problem, even on 'cold" grade 7 (or colder) plugs

I have tried changing the cold enrichment from 30 to 90 units and it makes absolutely no difference

i have also tried various adjustments to cranking enrichment with no change

the ignition side has been comprehensively tested

is there anyway i can check if the cold start function is even working or the ECU has a fault?

thanks

[CamB]

Not sure if its helpful but mine (a 3.2 litre Porsche with individual TBs and a moderate cam) has:

- warm up - 92.0
- post start - 120
- cranking - 162
- decay - 10


Are you sure the ECT sensor is working (so it knows to enrich it)?

[terryo]

thanks for those values. i'll compare.

yes, the temp sender appear to be working. both air and water temps are 22C before i start, so very close to workshop ambient. once warmed up water temp is 85-100C, so seemingly sensible