Needing throttle when engine is warm?Volvo 5.7 GI/E

russellh

could do with some advice on Volvo 5.7 GI/E needing throttle to start once warm?
engine starts from cold perfectly and runs fine with no issues. Today we went out to sea for about an hours cruise, switched off the engine for 30 mins or so and when I restarted I need to give her some throttle. Once started fine, no issues and cruised back to port. Once docked tried to restart and again needed a touch of throttle. Engine has been fully serviced with new leads, distributor cap, plugs, new manifolds and risers, water pump etc. All in tip top condition! 
Any suggestions as to why I need throttle once warm? Any advice much appreciated 

Russ

laureniac1

My 270 MPI does the exact same thing! Starts great but if we stop for a swim on the lake it takes some throttle. Hope you get some feedback I'll be interested 

russellh

I'm sure it's the engine cooling temperature sensor now after speaking to several people. Sensor thinks the engine is cold and throws fuel in which is why there is also the smell of unburnt fuel. It's a cheap fix apparently so will let you know the outcome was its been changed for a new sensor

Dream_Inn

interesting, please keep us updated

partlowr

Sounds like a gummed up idle jet in the carb.

[Deleted User]

I have an injected VP 5.0. Occasionally on a warm restart, as usual without using any throttle, I have to let the starter spin the engine for a second or two longer than normal until it starts. Basically I don't release the key until the motor fires up. It has never failed to start if I do this.

Until I learned this technique and I didn't give the starter extra time, if it failed to start on the third or fourth attempt I'd go to the "flooded" start technique, which is to push the shifter central button to disengage the transmission, move the throttle to the WOT position, start the engine, and when it fires up, shift back (quickly!) to the neutral position. I hope this makes sense. 
Andy  

06Rinker270

Careful starting an engine while flooded...make sure you wait a bit before starting.

I have had the same issue with my 350 and @andyd technique is the same I follow.  I also make sure to give time for the pump to start before I turn over, waiting for beeping to stop after key is turned. 

Wildboating

I had the same problem last year with both of my engines, the symptoms are the same as yours however there could be a number of causes for this symptom.  Have you checked your cylinder compression on each cylinder?  Unfortunately for me, my problem was tied to tuliped valves and low compression.

212rowboat

IAC... clean those rascals... or, replace them... if you clean them, make certain and don't move them dramatically... the mechanism sometimes has a hard time re-mapping it's position and will think it's wide open when it's not, or think it's closed tight, when it's not. 

[Deleted User]

I replaced my IAC four years ago due to an intermittent stalling problem, usually occurring at the worst possible moment during docking. The price for the part from Volvo Penta was three times the exact same part made by AC Delco through an auto parts supplier. Just FYI.
Andy

russellh

Thanks for the info

Glassguy54

I came across some interesting information regarding the IAC on Mercruiser 350 MAG MPI engines. Turns out its a Ford IAC made for their 2002 Windstar!!! Evidently the GM IAC is a 4 wire and the Ford, a 2 wire. According to a Merc tech, there were only 2 wires left on the ECM, hence the Ford 2 wire IAC.  I have not looked at my 350 MAG MPI to verify this yet, but just something to file for future reference, if a guy wants to bypass the $$$$Merc part and go to Advance Auto and pick one up. I don't know if Volvo is the same or not. 

andyrc

Dear friend, I just see you have asked the Volvo penta 5.7 Engine cannot warm start problem, I have meet same problem for my port engine, did you solve it finally? How to fixed it? Thanks a lot 

rinker270nb

I continue to have this problem on my 2016 383 Stroker repower w/ 100 hrs.  I am not getting an error code.  I've changed the wires and cap, IAC, disconnected and cleaned the sensors and thermostat wire plugs.  Has not solved it.  I am convinced it's an electrical sensor or computer problem.  Just can't find the error.  Very interested in hearing if any of you solve yours.