I need help with an 02' tige 20i.

[spharis]

The engine may have leaned enough to foul the plugs. That's an easy item to check.

[dogbert]

Ok, on your Merc MPI, if you haven't changed your distributor cap and rotor, then it's time to do so. I have to change mine about as often as the impeller. The distributor cap wears out unusually fast on this engine.

The other thing I had happen recently is that my fuel pressure regulator went out. It was still working fine, but it did alarm on the engine any time I went over 2500 RPM. My dealer told me that eventually it would stop running completely, in other words, I would lose power after a while. The regulator is attached to the outbound side of the fuel cooler. It should be easier to get to than it was on my V-Drive. It might be worth it to have someone hook your engine up and see what codes are being generated, or, better yet, check the fuel pressure.

[noworries]

The rotor and cap were replaced just recently it does have a knock sometimes but its not consistent. could it be fouled plugs?

Are you sure you got the plug wires back in their same holes when replacing the distributer cap? As an aside, I went to buy one this spring and the merc dealer wanted nearly $90 for the cap. Holy specialized marine part, batman. Is there a discount source for these things?

[soccerboy007]

Thanks you guys I finally figured out the problem it turned out it wasnt fuel related but ignition related. I followed dogbert's recommenndation and changed the cap and rotor.Then it hit me electronics 101 always check your source of ignition. It turned out that the ignition control module was bad. But thanks to everyone for all you help.

[R&T Babich]

... It turned out that the ignition control module was bad. ...

Do you know the part no. for the ignition control module? Is the module under the distributor cap? We've had our boat 2 yrs and I'm not familiar with the GM ignition system and haven't had the cap off.

[R&T Babich]

Ok, on your Merc MPI, if you haven't changed your distributor cap and rotor, then it's time to do so. I have to change mine about as often as the impeller. The distributor cap wears out unusually fast on this engine. ...

dogbert - what wears out on your distributor caps? That seems unusual. Do the contacts get grooved, because that would indicate the shaft bearing is worn and allowing wobble in the shaft. If the contacts are all pitted, are they brass or aluminum?

[soccerboy007]

the ignition control module is next to the ignition coil. go to the sticky for mercruiser parts and you can see a diaghram, that should help you to let you know location and also what it looks like.

[R&T Babich]

My ignition coil is mounted all by itself on the back of the block. I moved it to another hole to make it easier to route the plug wires. The parts diagram for my engine does not show a module. I'm wondering if the ignition module function is built into the ECM.

[dogbert]

dogbert - what wears out on your distributor caps? That seems unusual. Do the contacts get grooved, because that would indicate the shaft bearing is worn and allowing wobble in the shaft. If the contacts are all pitted, are they brass or aluminum?

You would think so, but not according to my service tech. The contacts don't get grooved, they appear to wear from arc'ing

They are aluminum, so I'm sure that's part of the problem. The rotor doesn't seem to go bad, but I have spares for both just in case. I've only replaced the rotor once, but am on my nth distributor cap (I lost count). It gets so bad that after a while, your boat won't even start.

This is one of the things that was much better on the Marine Power engines.

[dogbert]

BTW, I never had this problem on my 4.3L V6 Mercruiser. In fact, in the 10 years I owned the boat, I don't ever recall changing the distributor cap.

It appears to only be a problem with their Tournament Ski Mag engine line.

Go figure, buy their top-of-the-line performance engine and have these problems.

[illiniboarder88]

Is there a fuel filter on that line other than the fuel water seperator? If so, how hard was that to get to?

[R&T Babich]

You would think so, but not according to my service tech. The contacts don't get grooved, they appear to wear from arc'ing

They are aluminum, so I'm sure that's part of the problem. The rotor doesn't seem to go bad, but I have spares for both just in case. ...

I used to have the contact arcing issue (aluminum contacts) with caps on my old Fords, especially when I changed them over to electronic ignitions. I started replacing the caps with ones that had brass contacts (Mallory or Accel) and never had any problems afterward. When we got our Tige I picked up as a spare a Sierra kit 18-5273 that is a cap & rotor. The cap has brass contacts. I just checked our Tige cap and it has brass contacts. I'm sure the cap is factory original (approx. 90 hrs). The contacts and the tip of the rotor have greenish powder on them, but they are not pitted.

I'll bet your 4.6L cap had brass contacts.

[TRD]

Is there a fuel filter on that line other than the fuel water seperator? If so, how hard was that to get to?

If you have the same engine I do, 350 mag MPI 315hp. It is on the drivers side front of the engine. It has a black plastic cover around it.
p/n's : NAPA: 3225 (18-7844) (MERC: 35-60494-1)
Hope this helps.