Having Hot Start issues

Centella

Recruit
Joined
Jan 11, 2023
Messages
4
Volvo Penta 5.7 Gxi-F always starts perfect when cold, but when it gets warmed up, you need to prime throttle (no need full open, 1/4 may be enough)
It Starts again fine if it sits for maybe 2-3 hours after running (requiring longer in summer time).
idle RPM are stable around 700 RPM.
Have no DTCs active and ECU triggers them whenever you disconnect a sensor e,g ECT.
Replaced thermostat, ECT, IAC, TP, MAP, Spark plugs, Ignition coil, FPR, Fuel injectors...
Fuel pressure is correct and engine performance as well, it reaches 30 knots easily at 4200 RPM, didn' t go further though it still has some RPM there.

Any thoughts on what might be happening ?
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
43,665
Welcome, looks like your using a parts cannon on the motor. Replace everything and you still have a problem. Replacing parts can add to and mask what is really happening. Must say you must have plenty of money to throw at it

What is motor serial number?

What was your fuel pressure readings when it would and would not start?
What is the MAP, ECT, TPS and IAC when cold and when it won't start?

What scanner are you using?

Did you replace parts with OEM of aftermarket?
 

Centella

Recruit
Joined
Jan 11, 2023
Messages
4
Welcome, looks like your using a parts cannon on the motor. Replace everything and you still have a problem. Replacing parts can add to and mask what is really happening. Must say you must have plenty of money to throw at it

What is motor serial number?

What was your fuel pressure readings when it would and would not start?
What is the MAP, ECT, TPS and IAC when cold and when it won't start?

What scanner are you using?

Did you replace parts with OEM of aftermarket?
I found BOSCH original equivalences for fuel injectors, MAP and FPR.
 

HiWard

Petty Officer 3rd Class
Joined
Sep 20, 2022
Messages
76
I found BOSCH original equivalences for fuel injectors, MAP and FPR.
Do you have a part number for the Bosch replacement injectors?

I've occasionally had hot start problems on my 5.7 GXi-HF and when it finally starts there's a smell of fuel from the exhaust. I suspected leaky injectors, so I cleaned them and have not had major issues since.
 
Top