Thread: rr ecu gone south?
06-27-2006, 09:30 PM #1
rr ecu gone south?
I have an 04 rxp with rr ecu, riva I/c, stage 1, 15/20r, thru hull exhaust, pro block offs, lightened top end on fresh motor. (the super charger set at 11lbs) new wear ring, new denso's, oil level is perfect, retard on the timing but ever since I got it back I couldnt get past 8300 rpm with a 14/20r at the time, threw in the 15/20 and cant break 8150 rpm, the motor dosent seem to max rpm or be as snappy as before the rebuild. could it be the new stainless valves (I dont really believe that) or an ecu going bad? had it out this weekend and was sitting in a cove (not running) and got out past the no wake, when I jumped on it it ran for 3-4 mins when it started to sputter and then died, I fired it back up right away and it didnt want to run if you were on the gas above 2300 rpm, it acted like it was out of gas but it had half a tank. no codes came up and it wasnt hot the oil was clean and I almost think its the fuel pump going out. my buddy pulled me in and since the boat would idle I let it for the 10 mile pull behind the boat, didnt want to force water in the motor. when I got it on the trailer it reved out for about 10 sec before it sputtered and died again. any thoughts?
06-28-2006, 02:49 AM #2
- Join Date
- Apr 2005
Try dropping the denso's and going back to the oem plugs. That solved my problems, I instantly got 300rpms that I lost. I have been hunting down this problem for months and kept forgetting the tip that was given to me by another member here. For some reason, the Denso's we're misfiring at high rpms, it would run good for like a second then drop down 300revs. Specially if you load the pump from a sharp fast turn.
06-28-2006, 03:33 AM #3
06-28-2006, 06:21 AM #4
How fresh and were are you located??
What is giving you 11lbs of boost as well??
RR sc impeller or one of Les Cook's kits??
06-28-2006, 08:03 AM #5
Are you running any aftermarket fuel controller? What about injectors? You just can't throw in a 11 lb s/c without adjusting the fuel. I would swap your RR ecu with your stock one and see if it runs better to 8100. That could help isolate the rr a little bit more.
06-28-2006, 08:06 AM #6Originally Posted by two2curupt
Two2curupt: The rr only gives 9.6 lbs @ 8500. I don't think he could be turning 11 lbs @ 8300 with that wheel, imo.
06-28-2006, 08:14 AM #7
He means he has his clutch slip moment at 11 ft. lbs
Your cam being retarded is more than likely the problem. You only retard the cam with the stock class ECU.
06-28-2006, 08:22 AM #8
Oh. Good catch Jer. My bad.
06-28-2006, 01:51 PM #9Originally Posted by GTXX
06-28-2006, 01:54 PM #10
STOCK CAM app.140/145
RR CAM app. 120/125 or so i have heard
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