Engine Hesitation 350 Merc

[Coat]

Hi,
I have a 99 21v Limited with a 350 Merc efi and I'm having some issues with hesitation. It is only during a start, usually when pulling up a boarder. I changed the fuel separator, and the plugs. It doesn't do it all the time but when it does it is very noticable. The guages will flicker and you can hear the pause. I understand there is a fuel kit that merc introduced. Has anyone experienced the same problem?

[Tip]

I've got the same problem in my 03 22v. I read somewhere the problem was caused by the electronic fuel control module not being programmed correctly but I have not been able to get Merc to respond.

[Matt Garcia]

Their was a past discussion about this topic, click here for the thread. (http://www.tigeowners.com/forum/showthread.php?threadid=406&highlight=Engine+Hesitation)

[Coat]

Thanks,
I read the other discussions. I will let you know if I get it fixed. If you hear anything from Merc please let me know.

[ghollow]

Hey Scott,
Check your distributor and rotor. If they are carboned up it can cause a hesitation or a miss. I replace mine every 100 hours.

[Coat]

Thanks,
I'm on it. I was thinking about that.

[Tige M.D.]

Tip,
Greg again, I have a 03' 22v with a merc 350mag mpi that has a slight hick-up when easing into the throttle. The customer says it is much worse while pulling a rider. I brought this to mercs attention 18 months ago and denied there was a problem. I called on the customers behalf last week and they sending me a new ecm with a different calibration. But because it is out of warranty by six months they will only warranty the part not the labor. I have instructed my shop to eat the labor, customer pays nothing. Ihope the new ecm fixes it?

[Tip]

Greg,
Should I contact my dealer about getting a new ecm from Merc?

Thanks for the help,

Tip

[Tige M.D.]

yes, if they won't help you then let me know and i will try to work something out for you.
i should be getting the new ecm today. if it works then i'll let you know.

[Coat]

I my dealer recomended I replace the distributor module and it seems to have made a huge difference. More power, no hesitation and faster starting. Apparently there was a recent change to the module. I have only used it for two days but so far but it seems much better. The part was only $75.

[Tip]

Greg,
Thanks so much for the help! I will contact my dealer and see what he can do first.

Scott,
Can you get me a part number? If it's only $75, it might be worth a try. I want to give Tige a chance to resolve the issue first, though.

Thanks guys, there's hope!

[Coat]

I can try. Keep in mind my Tige is 99 21V. I will see what I can do this week.

[Tige M.D.]

the 03' does not have the same distributor as the 99'. totally different problem.

[Tige M.D.]

got the new ecm in the boat yesterday, did'nt seem to help at all. got the mercuiser westcoast tech rep out here and he told me "it is what it is". they are calling it a idle transition that all motors have. funny that the marine power votec 335hp doesn't do it?

so i guess we will have to just live with it.

[Tip]

Greg,
I really appreciate your effort on this issue, you have done much more than my own dealer and have helped me and many others on many issues.

This is where I would expect Tige to jump in and stand behind their decision to use Merc engines. The individual dealers just don't have the clout to get Merc to fix the problem. When the Merc rep said "it is what it is," what he was really saying was "tough S*** we're not going to spend the money to fix it." To use the excuse that all engines have the problem is complete hogwash, I've never heard of an Indmar engine having this problem, and I've never driven a car that had this problem.

I love my Tige, but it's issues like these that will make me think twice about buying another one.

[Tige M.D.]

the engine that is in your boat was most likely chosen buy your dealer. tige will put a merc, marine power, or pcm in their boats. the dealer is who decides what they want on their floor. we chose marine power last year and leave pcm and merc as options.

something to think about: last year at our owners regatta we had approx. 140 boats show up. my mechanics and i worked on 38 boats. all were mercruiser. this year we had 160 boats and we worked on 12. all were mercruiser. so, in 2 years i have yet to work on a marine power at our regatta's. i just think they (marine power) still give a crap about their product.

the 1 and only pcm we sold has been perfect so far.

[Tip]

Those stats do not bode well for Merc. I did not know about other engine options when I ordered the boat I had a Merc (5.0L) in my previous boat and it never gave me any problems. I have a friend who has a different boat but same engine as mine (5.7 MPI) and his does not hesitate. His engine is two years older than mine though. Sounds like Merc did something to the engine in 2003 and just does not want to own up to fix it.

Based on some of the problems other Merc owners are experiencing I should consider myself lucky, other than the hesitation problem my engine has been trouble free...knock on wood!

Thanks for all the help, if you hear about anything that might fix this please let me know.

[Tige M.D.]

ya know tip, i was repairing a start problem on a volvo penta 5.7 today and once i got it running i decided to check it for the same hesitation as the merc has. guess what? it did the same thing. i don't think it is as noticable due to the stiff throttle handle they use.

your 5.7 is not the 5.7 from 2 years ago. when gm decided to allow the new 5.7 to be marinized it changed everything for us mechanics. new cooling system, new ecm that will actually think for itself, vertually no distributor and crank position sensors. i am not so sure it is all mercs fault. i am just tired of hearing their ho-hum comments.