Cold start issue with my newly refreshed CIS

[Jameel]

Originally Posted by DRACO A5OG

If I may, you really should not be sitting at idle, just drive off so the parts get enough oil to avoid undue wear.

I usually set off pretty quickly. Certainly in less than a minute. I find if I set off immediately though, then CIS hasn't warmed up and I get some hesitancy for the first block. When I let it "warm up" in the driveway for maybe 30 seconds, I don't get that hesitancy usually. So you're saying that on cold starts, and low oil pressure the parts aren't getting enough oil? My brother likes to idle his car before taking off sometimes for a few minutes, but I've ready its not the best idea.

[Jameel]

Originally Posted by T77911S

could be fuel pressure has built up
mixture (CCP) could be off and the second start just clears things up. perhaps plugs. what heat range are you using. how do the plugs look. take a look at them when warm and after a cold start. look for wet ones.
mixture could be slightly off.

remove the connector on the top rear of the AFM. when cold, turn the key on and let pump run for 5 seconds then start

The part about "clears things up" sounds plausible from my end.

Plugs were selected by my mechanic, a knowledgeable guy. I haven't pulled them since the rebuild 2500 miles ago. But I will. I did do all the CIS tests and ran an AFR meter in the tail pipe after the rebuild to get my AF mix dialed in.

So if fuel pressure has built up between drives, how does letting the pump run for 5 seconds relieve this? Does it equalize in the FD and return to tank?

[Dumont]

Originally Posted by Jameel

....My brother likes to idle his car before taking off sometimes for a few minutes, but I've ready its not the best idea.

Actually it has nothing too do with liking to let it idle, it's just that I often get distracted by how much better my car looks in the garage sitting next to yours.......or it's because I don't really ever get to see your car, it being in the rear view mirror most of the time.........either that or I've got a sandwich needs tending to.

Either way, once she's on, I'm not shutting her down just to save some idle time. Either this Germanic machine can take it or I'm not interested.

[T77911S]

you can run the pump before a cold start, see if that helps with first start up.

I understand that with the first start it runs bad but if you shut it off then restart it starts fine, correct?

[Jameel]

Yep, starts immediately every time. Start immediately on the restart too.

[Jameel]

Originally Posted by T77911S

remove the connector on the top rear of the AFM. when cold, turn the key on and let pump run for 5 seconds then start

Ok. I just did this. It fired right up and idled immediately at 1000rpm. But that doesn't tell me much, since it does this on its own maybe 30% of the time. I still haven't tested my TTS, but given that the car starts 100% of the time on the first crank, I think I'm getting cold start injection just fine.