Five O'Clock
Petty Officer 1st Class
- Joined
- Apr 24, 2005
- Messages
- 251
First off, thanks for looking and trying to offer some help, I appreciate it. Here is my issue and the steps I've been through so far:
About 6 weeks ago, my 2003 Monterey 245CR with a 5.7GXi-E would start fine, I'd bring her out for the day, anchor somewhere, try to start her and she would crank, sound like she wants to run, but wouldn't turn over. I'd increase throttle and she'd start. This happened 1 more time and I had to get towed in. She would crank and crank but just could not get her running. Seems like she wasn't getting enough fuel, or some of the plugs wouldn't light.
Once we got back to dock, I called the mechanic and we walked through the following steps and symptoms:
- Put a fuel pressure gauge on the High Pressure pump, and noticed the pump would prime around 55psi, but once started would drop to 50psi, and as we increased throttle at dock (under no load), fuel pressure would drop to 30 psi, then 20, then backfire a few times, then back up to 40, then drop, etc.. The engine would rev up and down on it's own
- Did a full tuneup - wires, plugs, cap rotor, still no luck
- We replaced the fuel pump, got her running ok on the low pressure pump, took her out for a test ride, once we hit above, call it 1800rpm's, the engine would jump up and down with similar psi as above, and backfire, we backed her down and brought her back to dock.
- We started her back at dock, and the mechanic tapped on the fuel pressure regulator and she would get right back up to the 55 psi that she needed. Before this, she would jump from 800 rpm to 1800 rpm, up and down and so on.
- Replaced fuel pressure regulator with new E clip, and still no luck
- We hard wired one of the pump harnesses (looking back I'm not sure which one) to the battery, and the psi still jumped from 50 to 10psi and all in the middle
- Removed the fuel line supply, grabbed a jug of fresh gas and ran a hose to the fuel pump to make sure it was not the supply tank or anti-siphon valve, still the same issues
- Mechanic thought the new fuel pump we got was bad, I returned that, got a new one, installed it
- As you know, when you turn the key on these engines, the fuel pump primes itself for 3 or so seconds, I always wait for that to finish before starting... However when we installed the 2nd new pump, when turning the key, the fuel pump wouldn't prime, we just heard a click from the fuse box. After some wiggling and pulling and swapping, we got the pump to prime, and the engine to start, but STILL the same issues as above, fuel pressure was jumping all around. This time she would idle around 700 rpm, then drop to 250 rpm, then back up to 1200, 250, 700, etc. all on her own
- Tried replacing both the starting and the fuel pressure relays, thinking they might be faulty as the 2nd new fuel pump wouldn't prime, it would just give off a click
- After replacing the relays, still the same issue.
And here is where we stand today. I read this post from a few years back where BigDeal had almost the exact same issue and replaced his fuse box, but I'm not sure if that ever resolved the issue:
http://forums.iboats.com/forum/engi...53407-2003-5-7-gxi-fuel-pump-regulator-issues
I also want to note, that I washed the engine room and engine down with an engine degreaser and rinsed with water a few weeks before this all started happening. I tried to stay away from the ECM and fuse box and injectors as best I could, but I'm hoping I didn't short something out during all of this. This mechanic does have a Volvo diagnostic tool, but hasn't ran a scan yet.
Any thoughts on where we should go next? I'm happy to answer any questions you may have as well.
Thanks again for your help,
Dan
About 6 weeks ago, my 2003 Monterey 245CR with a 5.7GXi-E would start fine, I'd bring her out for the day, anchor somewhere, try to start her and she would crank, sound like she wants to run, but wouldn't turn over. I'd increase throttle and she'd start. This happened 1 more time and I had to get towed in. She would crank and crank but just could not get her running. Seems like she wasn't getting enough fuel, or some of the plugs wouldn't light.
Once we got back to dock, I called the mechanic and we walked through the following steps and symptoms:
- Put a fuel pressure gauge on the High Pressure pump, and noticed the pump would prime around 55psi, but once started would drop to 50psi, and as we increased throttle at dock (under no load), fuel pressure would drop to 30 psi, then 20, then backfire a few times, then back up to 40, then drop, etc.. The engine would rev up and down on it's own
- Did a full tuneup - wires, plugs, cap rotor, still no luck
- We replaced the fuel pump, got her running ok on the low pressure pump, took her out for a test ride, once we hit above, call it 1800rpm's, the engine would jump up and down with similar psi as above, and backfire, we backed her down and brought her back to dock.
- We started her back at dock, and the mechanic tapped on the fuel pressure regulator and she would get right back up to the 55 psi that she needed. Before this, she would jump from 800 rpm to 1800 rpm, up and down and so on.
- Replaced fuel pressure regulator with new E clip, and still no luck
- We hard wired one of the pump harnesses (looking back I'm not sure which one) to the battery, and the psi still jumped from 50 to 10psi and all in the middle
- Removed the fuel line supply, grabbed a jug of fresh gas and ran a hose to the fuel pump to make sure it was not the supply tank or anti-siphon valve, still the same issues
- Mechanic thought the new fuel pump we got was bad, I returned that, got a new one, installed it
- As you know, when you turn the key on these engines, the fuel pump primes itself for 3 or so seconds, I always wait for that to finish before starting... However when we installed the 2nd new pump, when turning the key, the fuel pump wouldn't prime, we just heard a click from the fuse box. After some wiggling and pulling and swapping, we got the pump to prime, and the engine to start, but STILL the same issues as above, fuel pressure was jumping all around. This time she would idle around 700 rpm, then drop to 250 rpm, then back up to 1200, 250, 700, etc. all on her own
- Tried replacing both the starting and the fuel pressure relays, thinking they might be faulty as the 2nd new fuel pump wouldn't prime, it would just give off a click
- After replacing the relays, still the same issue.
And here is where we stand today. I read this post from a few years back where BigDeal had almost the exact same issue and replaced his fuse box, but I'm not sure if that ever resolved the issue:
http://forums.iboats.com/forum/engi...53407-2003-5-7-gxi-fuel-pump-regulator-issues
I also want to note, that I washed the engine room and engine down with an engine degreaser and rinsed with water a few weeks before this all started happening. I tried to stay away from the ECM and fuse box and injectors as best I could, but I'm hoping I didn't short something out during all of this. This mechanic does have a Volvo diagnostic tool, but hasn't ran a scan yet.
Any thoughts on where we should go next? I'm happy to answer any questions you may have as well.
Thanks again for your help,
Dan
