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Bryan Tuvell 33ZX
03-22-2003, 12:34 PM
You may remember I have been having to feather the throttle to get my EFI 502 to start, once started, she is fine. (since new SM exhaust, plugs, cap, coil, all factory parts.)
Today, water test;
She ran great the first 20 minutes, up to 4500 RPM, then a loss of higher RPM, TACH IS ALL OVER THE PLACE, so we limped back at 2000 RPM.
She starts fine, but that is it.
HELP :(

I will have our club mechanic look at it, ideas?

I think distributor and timing?
Bryan

<small>[ March 23, 2003, 08:48 AM: Message edited by: Bryan Tuvell 26ZX ]</small>

Bryan Tuvell 33ZX
03-22-2003, 02:44 PM
Thanks POODLE, (new wires too, one had rubbed thin, rigged poorly) the rotor was a bear to get off when we changed it, I think it is something minor, (TACH is very erratic) our Merc guy makes house calls so I left it on the hose and key in it at the house.
The war has me working much more than normal.

Boy the new exhaust was sweet! I know there is supposed to be no performance gain but we picked up 2MPH on GPS at 4000 RPM, ran 5 degrees cooler too, I was surprised, she also was much more responsive to plane. I never got to take her above 4500 due to the issue that arose.

Again, I think that cap and rotor is the vilan, timing, we'll see soon. That is why we sea trialed early, to get the bugs out now, not later.
Thanks
Bryan

<small>[ March 22, 2003, 02:59 PM: Message edited by: Bryan Tuvell 26ZX ]</small>

fasttrucker
03-22-2003, 03:02 PM
I remember my first day out with my new exhaust,although i added a k+n filter,reprogramed ecu,diff prop at the same time...gained 6-7 mph.Also the boat just sounds so much better,like a performance boat should.Good luck!

Bryan Tuvell 33ZX
03-22-2003, 03:04 PM
I went out all stock (minus Ex Manifolds), prop included, we wanted to verify our normal baseline RPM/MPH before we ran our new prop.
WE should be back in operation this weekend.
I am confident it is something minor.
Bryan

BigGrizzly
03-22-2003, 03:08 PM
Bryan you may have a loose oil pressure wire or bad sender and the engine is in the limp mode. If it was ECM programing it would have done it from the start.

Bryan Tuvell 33ZX
03-22-2003, 09:20 PM
Great speaking with you Randy, I will keep you posted.
Bryan

tailwind
03-22-2003, 11:31 PM
Hi Bryan:

Sorry late to see your post however check these first:

Your irregular tach and ign indications are most certainly do to ign problems for which you have already estimated. Having seen identical problems in older systems - Chrysler etc. - My immediate suggestion would be:

1. Replace your no 1 coil wire - and recheck. This will maybe not the problem!
2. Replace your coil, with another good one - from either your ford or chevy, ha, ha. If you are a betting man or not this will "I bet" will solve your problems.

The combination tach / ign problems will lead only to your coil / lead etc, anyone want to put money on their mouth?

Bryan Tuvell 33ZX
03-23-2003, 06:21 AM
Hey can someone explain this limp mode, with the ECU need to be reset now if I find the problem?
I went ahead and burnt a vacation day today to try to find the issue before the mechanic gets here.
Bryan

Bryan Tuvell 33ZX
03-23-2003, 07:47 AM
Plugs look brand new.
ALL wires are clean and snug, all connections snapped firmly in place.. Grounds are clean.
Dist Cap, one screw was hard ro remove, possibly it was binding, fixed.
Neighbors get 20 more minutes of sleep until I fire her off.

What actually gets reset from the red button breaker on the engine?
Bryan

Bryan Tuvell 33ZX
03-23-2003, 08:45 AM
Well, sometimes I am my own worst enemy and forget the saying of not to fix what is likely not broke!

Stuck the old coil on and FIXED.
Runs like a champ.

I still have the have to give it a tad of gas issue to start her. I will next see if any codes are in the ECU.

Thanks guys, Bryan

BigGrizzly
03-23-2003, 05:02 PM
Great Bryan now your becomming a Master Tech. I hope the true story of me at Daytona putting in new plugs just before the @00 race spured that on. I think the burnd vaction day was worth the education.

Bryan Tuvell 33ZX
03-23-2003, 06:12 PM
Randy, too funny, basic trouble shooting is the extent of my skill.
But I do read and apply the knowledge.

Been a sad day for the country, we spent the rest of the day watching TV.
Thanks
Bryan

<small>[ March 23, 2003, 06:13 PM: Message edited by: Bryan Tuvell 26ZX ]</small>