Fg hot cranking issue

[Enzo]

After some advice fg xr6 na + T tuned been having an issue, cold start in cold weather car starts first crank but if the cars been sitting in the heat or sitting for about 20 min after car was running at normal temp the car will take a while cranking approx 3 seconds before it starts and sometimes it stalls after first crank tuner said he can’t fix it as everything on tune looks good, he had it for a week did a few touch ups but still no luck any idea what it could be? Cheers in advanced 

Running a na engine bare with all turbo factory parts 

[k31th]

Well, if the tuner said it's not in the tune, either the tuner is incompetent (unlikely) or needs to look at the airflow, fuelflow, compression etc and resolve it in a more mechanical way as it's obviously a problem that a mechanic should be able to solve.

 

But running an N/A engine with turbo stuff could be any sort of problem. Impossible to accurately diagnose over the internet.

[Enzo]

Looks like I’m gonna run a compression test tomorrow and see how it goes, should be 190 across all cylinders correct? Also the tuner is a good company who does mainly jdm cars pushing big power however did another fg turbo with factory turbo engine but no problem only problem we both have in common is black smoke puff on startup only once not continuous. 
Thanks again 

 

also pushing 15psi locked 

and running turbo factory bf map sensor 4 bar 

Edited 11/12/21 09:04 AM by Enzo

[4321]

also check fuel pressure

[k31th]

As long as all of the cylinders are close to each other, the number doesn't matter too much. If they all have bad compression, you'd know it already ahha.

[Enzo]

Thanks for the advice I’ll see how it goes hopefully not the rings haha, how much is acceptable in reference to psi being close to each other per cylinder