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SWeaver
08-31-2012, 02:24 PM
2003 mcx 205v 300hrs

Engine starts fine, but idle surgeing within about 125 rpm or so. Accelerating to pull a skier from a stop.....acceleration is weak, engine runs roughly and about 2000 rpm as we accelerate, the check engine light goes on. This is a repeatable action. I disconnected the battery and have tried again multiple times with the exact same behavior.

I checked spark plugs and wires. all seem are ok. Check engione light goes out when I reduce back to idle. Sounds/acting similar to when my 2000 ford explorer had a bad ignition coil for a couple cylinders if that helps.

Is there any way to pull the engine codes (OBDII etc?) without going to a dealer? Would it have to be an MC dealer any indmar? What else could I test/look for?

Thanks!

SWeaver
09-03-2012, 11:43 AM
Still having trouble. Replaced plugs, wires, distrib cap and rotor, coil, and fuel pump.
Anybody got suggestions? Wont run under any load, in neutral it will run fine at any rpm above about 1000. Idle is poor though....im at a loss...

ranger098
09-04-2012, 01:56 PM
i think that you are having the same problem as me. have you ever had a problem with water in your gas tank? i think it could be somehow related to this, maybe a bad fuel filter. have you checked fuel pressure?

maybe we can work this one out together!

SWeaver
09-04-2012, 03:35 PM
Any help is appreciated. Already drained tank. No water. Fresh gas. Good fuel pressure. New pump anyway cuz it was getting louder.

What year boat you got and which engine?

ranger098
09-04-2012, 06:04 PM
i have an 04 X2 (v drive) with a predator 310 engine. my boat seems to only do this when it wants to, i had it out running well for a few hours then all the sudden just refused to accelerate. not sure if the problem is still there now (when the engine is cold), need to test that still sometime this week

Jerseydave
09-04-2012, 06:31 PM
I think you need to pull codes, and maybe your MC dealer is the best place to start.

Have you checked connections on all sensors? (knock sensor, TPS, etc.)
What's the engine temp and oil pressure?

JimN
09-04-2012, 06:48 PM
Still having trouble. Replaced plugs, wires, distrib cap and rotor, coil, and fuel pump.
Anybody got suggestions? Wont run under any load, in neutral it will run fine at any rpm above about 1000. Idle is poor though....im at a loss...

Stop throwing parts and money at it and do some diagnostics. Also, check your oil cooler and impeller. Did you start another thread about this? I could swear I posted the same answer earlier today.

SWeaver
09-04-2012, 09:04 PM
Stop throwing parts and money at it and do some diagnostics. Also, check your oil cooler and impeller. Did you start another thread about this? I could swear I posted the same answer earlier today.

Thanks jimn for your help. This is the only post ive made personally, but ive read your "stop throwing parts" advice on many others' threads while looking for answers. I only did the above parts because they were all original (10yrs old) fairly inexpensive, easy and just about due to fail according to what ive read. Now that none of that worked, im back to searching for answers.

As i mentioned, this is NOT an occassional issue. It is occurring every time i put the throttle down....so it shouldnt be too tricky, right?

I checked the timing and it appears it is off. 22 ish degrees? I think i read it is supposd to be 10. Not sure how that would happen. Checked at 1000rpm, no load. The painted marks on eng and distr still line up and the distr isnt loose.

Engine temps,oil pressure are great, impeller is good (new in spring but double checked it), old plug's color looked good when i replaced them. No gas smell in exhaust.

Will do a compression test thursday night. No evidence of water in oil.

I would jump the codes, but i read that sometime around 2003, MC changed something and that the change made it a bad idea to jump. How can i tell if mine is safe to do that?

I also read that the timing isnt adjustable like the older boats. Sooooo, if timing is off how do i fix that?

Thanks again!

SWeaver
09-04-2012, 09:12 PM
Thanks dave,
I havent looked at sensor connections yet. Is there a way to test the sensors? Which ones are you suggesting? Tps, knock, probably coolant too...any others?

Mc dealer is 2hr drive each way. Ill take it there for codes if i have to, but i am trying ti figure out if i can safely jump my2003 with the paperclip trick, or if any indmar dealer can pull codes....i got a couple other brand dealers 20min away, but i dont particularly want to do that either if i can avoid it.

JimN
09-05-2012, 09:21 AM
Thanks jimn for your help. This is the only post ive made personally, but ive read your "stop throwing parts" advice on many others' threads while looking for answers. I only did the above parts because they were all original (10yrs old) fairly inexpensive, easy and just about due to fail according to what ive read. Now that none of that worked, im back to searching for answers.

As i mentioned, this is NOT an occassional issue. It is occurring every time i put the throttle down....so it shouldnt be too tricky, right?

I checked the timing and it appears it is off. 22 ish degrees? I think i read it is supposd to be 10. Not sure how that would happen. Checked at 1000rpm, no load. The painted marks on eng and distr still line up and the distr isnt loose.

Engine temps,oil pressure are great, impeller is good (new in spring but double checked it), old plug's color looked good when i replaced them. No gas smell in exhaust.

Will do a compression test thursday night. No evidence of water in oil.

I would jump the codes, but i read that sometime around 2003, MC changed something and that the change made it a bad idea to jump. How can i tell if mine is safe to do that?

I also read that the timing isnt adjustable like the older boats. Sooooo, if timing is off how do i fix that?

Thanks again!

I checked the PM from EngineNut and they changed to the CAN system in '05, so you can use an OBDI scanner to put it in Diagnostic Mode, or a paper clip. Insert the wire into terminals A and B, start it and manually set the RPM at 1000, watching the check engine light to see if you have any codes. I would guess you'll see 33 and/or 34, indicating a MAP sensor issue. You would set/change the timing the same way as any other engine- loosen the hold-down, rotate the distributor and watch the timing mark.

DO NOT grab the distributor cap when you adjust the timing unless you want a handful of spark. This delivers about 50K Volts and doesn't make for a good day.

You can't see the actual timing advance unless it's in Diagnostic Mode because the timing mark will jump around. It does that, right?

SWeaver
09-05-2012, 08:25 PM
Thanks jimn, great help and answers all around!
Your last sentence asked about the timing jumping around. As i was checking it a couple days ago, it seemed to bounce within about 5 degrees or so. Will it always do that if not in diag mode, even on a healthy engine? i will get out to work on it late thur or fri mornin with a much better idea of how to proceed. Thanks again!

SWeaver
09-06-2012, 10:22 AM
If the code is for a bad map/tps/coolant sensor, are they specific indmar parts or would any napa/autozone automobile parts store have them?

LYNRDSKYNRD
09-06-2012, 10:42 AM
@ JimN.....I was just in my local Orielly yesterday and saw that they loaned out OBDI scanners will these work on boats or is there a marine specific scanner

JimN
09-06-2012, 10:50 AM
If the code is for a bad map/tps/coolant sensor, are they specific indmar parts or would any napa/autozone automobile parts store have them?

If you remove the transmission, oil cooler, exhaust/intake manifolds, raw water pump and very few others parts, it's all GM.

I have been going to O'Reilly because a lot of their parts come with lifetime warranty, although I would use AC/Delco parts for this kind of thing.

JimN
09-06-2012, 10:51 AM
@ JimN.....I was just in my local Orielly yesterday and saw that they loaned out OBDI scanners will these work on boats or is there a marine specific scanner

That won't really show you more than a paper clip will and I doubt the scanner will mate with the ALDL (AKA 'DLC') connector. The only way to really see data is to use a diagnostic computer and most of this will be in real-time.

93Prostar190
09-06-2012, 04:50 PM
A Diacom scanner would do the trick! I am the happy owner of one!

SWeaver
09-06-2012, 09:12 PM
I got jimn helping me...who needs a diacom? :-)

rockcrwlr72
09-07-2012, 05:03 AM
I know it's a pain but pull your distributor and check the internals. It may simply need a rebuild, new bushing, springs, etc. A bad distributor pulling too much timing can easily make the healthiest engine run like crap. 22 degrees of timming? Something is wrong, all small blocks big blocks should be in the 10 degree range. Does your engine PING under load? Is it carburated or fuel injected?

JimN
09-07-2012, 06:30 AM
I know it's a pain but pull your distributor and check the internals. It may simply need a rebuild, new bushing, springs, etc. A bad distributor pulling too much timing can easily make the healthiest engine run like crap. 22 degrees of timming? Something is wrong, all small blocks big blocks should be in the 10 degree range. Does your engine PING under load? Is it carburated or fuel injected?

A bad IC module might cause problems but it's only a 2003 boat- that's awfully young to have a bad distributor. I have a '90 Silverado with about 300K on it and all I have done it replace cap/rotor/wires/plugs WRT ignition.

CantRepeat
09-07-2012, 06:53 AM
I got jimn helping me...who needs a diacom? :-)

I've given some serious thought to making the DIACOM purchase and it really hasn't been that hard to want to follow through on it. I've got an 06 and I'm sure I'd never go back to an older model boat so it make prefect sense for me to get the tools I will need to continue to work on my own boats.

SWeaver
09-07-2012, 09:51 AM
codes 42 and 81....ig control mod? timing at 1000rpm was about 28 degrees on a warm engine, no load. i used the timing light on all plug wires and it was frequently erratic on all cylinders. is that a bad IC symptom? any way to check that....or what is my next step?

edit for more info......idle rpms, when cold seem to be relatively stable, but after just a few minutes, begin to do a "rythmic" fluctuation of about 600-800 rpm.

CantRepeat
09-07-2012, 10:45 AM
codes 42 and 81....ig control mod? timing at 1000rpm was about 28 degrees on a warm engine, no load. i used the timing light on all plug wires and it was frequently erratic on all cylinders. is that a bad IC symptom? any way to check that....or what is my next step?

edit for more info......idle rpms, when cold seem to be relatively stable, but after just a few minutes, begin to do a "rythmic" fluctuation of about 600-800 rpm.

42 Electronic Spark Timing Grounded Circuit

81 has a pretty big list of what it can be. EngineNut, the Indmar tech guy, had posted that most of the time this was a grounding issue. Given that your code 42 is also some sort of grounding issue they both could be related.

EngineNut's advise to another user was to check for corrosion on the battery cable connected to the block.

JimN
09-07-2012, 10:46 AM
codes 42 and 81....ig control mod? timing at 1000rpm was about 28 degrees on a warm engine, no load. i used the timing light on all plug wires and it was frequently erratic on all cylinders. is that a bad IC symptom? any way to check that....or what is my next step?

edit for more info......idle rpms, when cold seem to be relatively stable, but after just a few minutes, begin to do a "rythmic" fluctuation of about 600-800 rpm.

Did the scanner put the ECM in Diagnostic mode (did you use a scanner?)? If not, you need to do that. If the timing mark was unstable, it tells me that it wasn't in that mode because in Diagnostic mode, the timing mark is rock-steady because spark stabilization is disabled. You'll also see a drop in RPM and it may not want to keep running but raising the RPM to 1000 keeps it going. In normal operation, the timing mark SHOULD jump around.

With the key OFF, unplug the harness from the distributor that DOESN'T go to the coil (this one will have a purple/white wire) and inspect the pins and terminals. Also, remove the distributor cap and inspect the distributor- if there's a lot of rust, it's possible that the cap has a crack, has been loose or the gasket is torn/missing.

Make sure the base of the distributor and the block/intake manifold are clean. Also, make sure the hold-down bolt is tight. If it's not tight enough, the distributor shaft can creep.

If you used a paper clip to connect terminals A and B but the timing mark kept jumping around, it's possible that the IC module is bad. If you have access to a service manual, look at the procedure for verifying this.

SWeaver
09-07-2012, 11:50 AM
Just for closure.....

Thanks everybody for your help. after all that, it was indeed a short.

I went back out to check more things and the ign key wouldnt do anything when placed in the ON position. I started jiggling wires and found a short in a wire bundle under the dash. mysteriously, the PerfPass RPM readout had gone out a few days ago and that was where the short was. all better now.....
Thanks again!

side notes....
what is the proper procedure to check timing on this engine. i know 10 BTDC but is that under load or at idle, 1000rpm? and on cylinder 1 (on a vdrive is the furthest rear on driver side, right)?

ranger098
09-07-2012, 11:52 AM
great to hear! i love a happy ending. ill have to check my wiring also and see if it is that simple for me too. happy riding.

CantRepeat
09-07-2012, 12:04 PM
Just for closure.....

Thanks everybody for your help. after all that, it was indeed a short.

I went back out to check more things and the ign key wouldnt do anything when placed in the ON position. I started jiggling wires and found a short in a wire bundle under the dash. mysteriously, the PerfPass RPM readout had gone out a few days ago and that was where the short was. all better now.....
Thanks again!

side notes....
what is the proper procedure to check timing on this engine. i know 10 BTDC but is that under load or at idle, 1000rpm? and on cylinder 1 (on a vdrive is the furthest rear on driver side, right)?

As Jim had outlined: The ECM must be in diagnostic mode, which he also explained how to do in an earlier post. It was right after you posted about the timing jumping around.

Timing is always on #1 @ idle.

SWeaver
09-07-2012, 02:18 PM
So, just by jumping A B with a paperclip (or an OBD 1), that puts it into diagnostic mode? (IE when the check eng light is blinking). I misunderstood that. Not used to newer technology mainenance yet... I thought that diagnostic mode was something you did with a laptop and special software out on the water. It makes alot more sense now after i spent more time fixing it. Thanks again everybody!