M20b25 swapped, hard cold start, stalls warm unless icv unlugged

[jlevie]

I increased the fuel pressure today from the stock 3.0 bar (44psi) up to 53psi (3.65 bar i believe) Now on a cold/cool start/restart the idle will rise to 750rpm, drop to 500-550 for about 10 seconds then hold at 750rpm, smoother than at stock pressure but still rough. on a hot restart or once warmed up the motor idles at 600rpm fairly smoothly but continues to knock until the clutch is depressed.

why the continued rough start? the increase in pressure seemed to help all round with idle, it made no difference to throttle responce, mileage or driveability. what would the increase in pressure indicate with the continued rough idle on a cold/cool start/restart? how much excessive wear is increasing the pressure causing? would cause the continued knock once warm at idle until the clutch is depressed?

Increasing the fuel pressure would tend to compensate for the lean condition that results from intake leaks. Get a smoke test run.

[Golfer_705]

Increasing the fuel pressure would tend to compensate for the lean condition that results from intake leaks. Get a smoke test run.

scotty kilmer smoke test preformed, intake leaks also check for using parts cleaner, starting fluid and propane. engine vaccume remains steady at 14 in.hg at idle

[Golfer_705]

It ended up being a faulty fuel pressure reading on the gauge when the pressure was set with the adjustable FPR. Set pressure with a new gauge and the motor now runs great. Sorry for the late reply, all the help from the forum is greatly appreciated