Volvo Penta 5.7 Gi-E Cranking but not starting (reliably)

[hodgenpodg]

I'm having an issue with my 2003 Volvo Penta 5.7 Gi-E and hoping I could gain some insight from users here as other posts have helped me a lot in the past (bad fuel pump at the beginning of the season).

I'll start with an issue that I started having about a two months ago just in case it might be related.

The engine was running perfect and would start up on the first try every time we went down. We did about a 1-1.5 hour drive and then anchored to have some lunch and swim (engine off for about 2 hours maybe less). When trying to start the engine I had the radio on loud and thought it started but it didn't (it may have started to turnover a little). I turned down the radio so I wouldn't stop cranking the engine till it was fully started and this time it wouldn't start (it would crank just fine). I thought maybe I just used the battery a little too much so i switched it to use both batteries and it still wouldn't start. I put the throttle in neutral and WOT and it finally started. (I looked this up and thought it could just be a leaky fuel injector and the engine was flooded and that was why putting the engine in clear flood mode worked but now I'm not sure). I replaced one of my older batteries (the other was already brand new) just in case but this same scenario happened the next three of four times we went out so I just kept thinking it was leaky warm fuel injector(s) and the clear flood mode kept working.

Two weeks ago I went down to go out and couldn't get the boat started at all. It would crank over nice and strong but just wouldn't start. I was going on vacation the next week so I didn't have time to diagnose but I was planning on replacing the fuse box as there is a service bulletin for that. I put the new fuse box on earlier this weekend and it still wouldn't start so I started finding all the different sensors (IAC, Crankshaft sensor, Camshaft sensor, TPS and others) so I would be familiar with their location when typing up this post. I did maybe slightly wiggle a few wires but didn't see anything in bad shape or exposed. Just before I was about to leave I decided to try it one more time and it fired right up and sounded great. I shut it off and let it rest multiple times and everytime it started right back up but I still had to get home. I went up this morning and it wouldn't start again. I tried a few things like putting in neutral and giving some throttle but nothing seemed to help it start but then seemingly randomly it started after maybe 10-15 tries and then would start fine every time after that.

My fuel pump is brand new so I don't think it is that but I am going to check fuel pressure on the rails next weekend. I also ordered a new distributor cap and rotor which I'm going to replace next week as well (I haven't had a friend to help me test spark at the distributor but its not a crazy amount of $$$ to replace the distributor cap and rotor so figured why not).

I'm wondering what other sensors would stop it from starting up so I could start to replace them and see if that helps.

Thank you.

 

[alldodge]

Agree, do replace cap and rotor

You replaced the fuel pumps but have you measured the pressure at the low and high pumps?

Get a spark gap tester and check for spark on a few cylinders
If it still does not start, while the motor is cranking see if the tachometer shows at least 300 rpm

 

[Maclin]

If it has a deadman switch, may be a factor if it is not making reliable contact inside. It is not related to throttle movement, other than it is in the same housing and maybe gets jostled/prodded at some point. Again, if it has one. Maybe exercising that switch would clean off some contacts, just sayin', something to try anyways.

 

[hodgenpodg]

AllDodge I have not tested the fuel pressure yet (didn't have the pressure tester on me) but I will this coming weekend.

I will try to test the plug wires but I have had trouble getting to them in the past (I was going to replace plugs and wires before the season just for fun)

The tachometer jumps way up when I first turn the key (if I remember correctly somewhere in the 1500-2000 rpm range) and then as I'm holding the key it stays around the 300 rpm mark. Is this normal?

Maclin I did check the kill switch at the throttle as other peoples posts lead me in that direction so I checked all the connections and everything was good. Also tried starting with the clip off the kill switch and there was no RPM jump on the tach and the fuel pump did not engage when I turned on the key (I'm assuming thats normal?),

Thanks for all the help I will update this weekend when I can get up to the boat. This weekend I'm going to replace the distributor cap and rotor, IAC and the TPS. I plan on doing one at a time so I can determine which one fixes it if any that way this post might help someone else with a similar problem.

 

[hodgenpodg]

Can anyone tell me what version of MEFI a 2003 Volvo Penta 5.7 Gi-E is? I'm considering buying an ECM scan tool to get some more insight into the engine. I plan on keeping the boat for a while and I'm sure I'll have more issues at some point in its lifetime.

 

[alldodge]

Without indepth research it's either MEFI 3 or 4 and both use the same connector

 

[QBhoy]

My money is on the diz cap and rotor.

 

[hodgenpodg]

Just wanted to post an update in case it helps anyone else with a similar problem.

I replaced the distributor cap and rotor this weekend (the old ones were in pretty rough shape) and attempted to start the motor but still wouldn't start (although it seemed like it wanted to more than before).

I hooked up the MEFI scan tool from http://obd2allinone.com/mefiscan.asp and looked to see if any trouble codes have been triggered...nothing

I had already purchased the a new TPS and IAC (the engine off reading of the IAC was about 114 steps) so I decided to get those put on (relatively easy only two screws for each sensor).

After putting those on and hooking up the MEFI scan tool the IAC sensor was reading around 58 steps with the engine off. (this was after going through the IAC reset procedure which my manual said was turn the key on but not started for 5 seconds and then turn key off for 10 seconds and then start the engine). The engine now started right up and the IAC steps went up into the mid 60 steps during idle and after a bit of time revving up to about 1500 rpms the IAC steps dropped back down to the mid 50's. I was able to successfully restart the engine several times before I had to head home. I didn't assume this had been fixed because my past two times to the boat I was able to get it started after about 10-15 tries.

I went up this morning to test a truly cold start and it fired right up on the first try.

Does any of this make sense? I'm not entirely sure what the IAC steps should be at when starting a cold engine. I was unable to test fuel pressure as I forgot my tester again.

 

[alldodge]

What ever it is, it does not sound like a spark issue (Tach at 300 rpm). In you previous post of giving it throttle an still not start would also not lead me to the IAC.

I tried a few things like putting in neutral and giving some throttle but nothing seemed to help it start but then seemingly randomly it started after maybe 10-15 tries and then would start fine every time after that.

this morning to test a truly cold start and it fired right up on the first try.

I would lean toward injectors not being turned ON (no fuel) and a bad connection or cam sensor. muc would probably have a better idea

 

[hodgenpodg]

Wanted to post an update on this. Checked high and low fuel pressure today. Got about 5-6 psi on low (with fuel pump on but engine not started) and when I started the engine it shot up to 10 psi. On the high side it was a constant 50 psi the whole time.

The engine didn't start last week and after unplugging and replugging in the connections to the ignition control module it started up again. I pulled the ignition control module off and it was a GM part not a volvo (is this normal?). I bought a Volvo OEM replacement and installed it. I went up this past weekend after the boat sat for two days and it started right up. Went up again today and it started right up

Does anyone have any thoughts? Could the low fuel pump be bad where its only reading about 5-6 psi and then going up to 10 psi when the engine starts?

 

[Walt T]

Hot starts not happening can be vapor lock. Simply using non ethanol fuel can cure it. But it sounds like you're having cold start problem too

 

[dypcdiver]

" I did maybe slightly wiggle a few wires but didn't see anything in bad shape or exposed. Just before I was about to leave I decided to try it one more time and it fired right up and sounded great."

This sounds like a poor connection to one of the sensors, perhaps replacing the IAC cleaned up the poor connection or disturbed the other wiring enough to get a reasonable connection.
Just my thoughts.

 

[hodgenpodg]

Thats what I'm thinking.

One of the connections to the ignition control module on the backside of the motor was pretty well pinched by a big hose so I reposition the new one so it won't get pinched. Just rescheduled my haul out for Friday morning so hoping it starts tomorrow morning and I can sea trial it while the wind is low.

 

[alldodge]

Don't see the low pressure pump being the issue, unless the pump doesn't turn back on while cranking. While it should be 8 this may be due to motor is cold and it can take a couple seconds for the first crank. You need the high pressure side to start the motor, and it appears to be doing ok.

Need to know why your not getting the injectors to fire. The distributor should be firing since your tach is showing 300

https://www.homedepot.com/p/Astro-P...SmAus71pP0ePJoVu7OxoC0QkQAvD_BwE&gclsrc=aw.ds

 

[aimlow]

Just wanted to post an update in case it helps anyone else with a similar problem.

I replaced the distributor cap and rotor this weekend (the old ones were in pretty rough shape) and attempted to start the motor but still wouldn't start (although it seemed like it wanted to more than before).

I hooked up the MEFI scan tool from http://obd2allinone.com/mefiscan.asp and looked to see if any trouble codes have been triggered...nothing

I had already purchased the a new TPS and IAC (the engine off reading of the IAC was about 114 steps) so I decided to get those put on (relatively easy only two screws for each sensor).

After putting those on and hooking up the MEFI scan tool the IAC sensor was reading around 58 steps with the engine off. (this was after going through the IAC reset procedure which my manual said was turn the key on but not started for 5 seconds and then turn key off for 10 seconds and then start the engine). The engine now started right up and the IAC steps went up into the mid 60 steps during idle and after a bit of time revving up to about 1500 rpms the IAC steps dropped back down to the mid 50's. I was able to successfully restart the engine several times before I had to head home. I didn't assume this had been fixed because my past two times to the boat I was able to get it started after about 10-15 tries.

I went up this morning to test a truly cold start and it fired right up on the first try.

Does any of this make sense? I'm not entirely sure what the IAC steps should be at when starting a cold engine. I was unable to test fuel pressure as I forgot my tester again.

Fuel pump, or fuel pump relay.