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Jason
Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 14301
Experience:  Degree in Marine Technology. Gas and diesel marine mechanic.
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I am Tarek I have a problem with the timing advance on

Customer Question

Hi, I am Tarek I have a problem with the timing advance on a 5.0L MPI 2006 engine.
JA: Thanks. Can you give me any more details about your issue?
Customer: Sure, at idle, the timing advance fluxuates between-4 and 2degrees read on the Rinda scan tool. When throttled up to 1000 the timing is at -14, at 1500 the timing is at -10, at 2000 the timing is at -6, 2500 and above stays at 10 degrees. When I return to idle the timing is at 12, at 1000 -17 degreres, 2000 -4 and at 3000 10 degrees. the timing advance seems to be all over the place and out of spec.
JA: OK got it. Last thing — Marine Mechanics generally expect a deposit of about $26 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 8 months ago.
Category: Boat
Expert:  Jason replied 8 months ago.
Hi Tarek, my name is ***** ***** I will be helping you today. Is the engine running poorly or not making full power?
Customer: replied 8 months ago.
Both, doesn't Rev up past 2000 under load, bogs down. Sometimes idles rough sometimes okay. When applying throttle heavily, sometimes backfires. On occasion stalls at idle but will restart. New iac valve, no change
Expert:  Jason replied 8 months ago.
Have you run a compression and fuel pressure test yet?How old is the fuel?When is the last time the engine made full power? What is the story/history on the engine?
Customer: replied 8 months ago.
New fuel, changed all filters. Boat ran well for an hour then bogged down on that engine. Limped back at 2000 rpm, slow and guttless. I am curious why the timing is so far out. Should be 8 degrees at idle, and 30 degrees at 3000. Other engines timing is good but this one is way off.
Customer: replied 8 months ago.
Fuel pressure is 40 pounds on the rail at 2000 rpm no load.
Expert:  Jason replied 8 months ago.
Don't worry about the timing yet. Timing on MPI engines is not linear, and it will change, especially if the engine is misfiring for another reason. Step 1 here is checking engine compression. Has that been done yet? If yes, what are the numbers on each cylinder? If no, do that first and get back to me with the numbers.
Expert:  Jason replied 8 months ago.
Hi Tarek. Any progress with that compression test?
Customer: replied 8 months ago.
sorry for the delay, compression test done.175 180
145 160
155 155
182 160The engine started up great, was sounding good and throttling up well (in neutral)
I hooked up the scan tool and the pressure guage to see if anything was up,
the timing advance was at 30 degrees at 3000 rpm and the fuel pressure at 38lbs.
After about 3 or 4 minutes the timing went out (-15) the fuel gauge went up to 40psi and the rps decreased to 1400 rpms.
with a fair bit more throttle it would go back up to 3000 but the timing only advanced to 10 degrees.
No codes during this.
Could this be a grounding issue or vacuum issue??
Thanks
Expert:  Jason replied 8 months ago.
Are you using the hand held techmate scanner, or the diacom laptop based scanner? On the fuel, did you add fuel to existing fuel that was in the tank? Or was the tank pumped dry?When was the last time the engine ran correctly?
Customer: replied 8 months ago.
I am using the techmate scanner. There was about half tank of fuel and we topped up with new. The boat ran well for an hour then fell off plane and started having these issues. That was about a week ago. Over the last few months when we haven't gone out I get down about once a week to start engines, shift the gears in and out of neutral and let engines warm up. Usually bring them up to 3000 for a few minutes and then back to idle and call it a day.
Expert:  Jason replied 8 months ago.
Start by getting a portable fuel tank filled with brand new gas and hook that up to the engine. Change/dump the fuel water separating filter on the engine. And See if it runs better on that portable tank. Let me know what happens.
Customer: replied 8 months ago.
Pulled the cool fuel filters and screen, looked good. Used portable jerry can with new gas and hooked up to cool fuel. Started engine, let idle for 5 min. Same problem, when throttling up timing goes way off and has trouble spooling up. At 3000 rpm timing stuck at 10 degrees. No codes.
I went by earlier today and started, ran well,timing up to 30 at 3000 rpm, was good for 3 or 4 minutes then rpms came down and timing went wonky.
Expert:  Jason replied 8 months ago.
What is the serial number on the engine?
Expert:  Jason replied 7 months ago.
Hello. Just checking in. How are we making out?
Customer: replied 7 months ago.
Sorry, just got slammed with work. Thanks for the push, I needed a reminder.
Engine Model Number 4M42037TT
Serial Number 0W615083Sorry for the delay
Expert:  Jason replied 7 months ago.
Got it. When was the last time the cap and rotor were changed?
Customer: replied 7 months ago.
Brand new. Plugs and wires 2 years ago
Expert:  Jason replied 7 months ago.
Was it doing the same thing on the old cap?
Customer: replied 7 months ago.
Yes, no difference
Expert:  Jason replied 7 months ago.
Pop the cap off, rotor off, and grab the distributor shaft and try to spin in back and forth, and pull up and down on it, and see how much play is in it. Also, can you transcribe the live data from your scanner with the engine running at idle. I'll have a look at it and see if anything looks out of place.

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