www.iFourWinns.com
https://www.smwebhead.com/phpBB3/

1994 OMC 5.0 EFI wont run below 1000 rpm
https://www.smwebhead.com/phpBB3/viewtopic.php?f=11&t=7171
Page 1 of 1

Author:  bryan9633 [ Wed Mar 16, 2011 9:17 pm ]
Post subject:  1994 OMC 5.0 EFI wont run below 1000 rpm

Hello All,

I have a 1994 FourWinns with an OMC 5.0L EFI motor. We are having issues trying to get it running under 1000 rpm. First thing in the morning it will fire right up for about 20 sec. then start to sputter and die unless I give it about half throttle. After it dies it will not start unless i go full throttle then when it starts i can't bring it down below 1000rpm. I have pressurized the intake system with 5 psi and sprayed down the intake, hoses, ect. with soapy water to cheak for vaccum leaks and found nothing. I have replaced the TPS, IAC Valve and plugs. Fuel pressure is 40psi @1000 rpm and adjusts fine when I apply vaccum to the regulator via hand pump. I just cant figure out why this thing wants to die below 1000 rpm and why it starts and runs fine the first 20 sec. each day. Any ideas?

Thank You!

Author:  Paul I. [ Fri Mar 18, 2011 12:55 pm ]
Post subject:  Re: 1994 OMC 5.0 EFI wont run below 1000 rpm

Sorry to hear of your problems!!!!!!!!!!!!!!!!

You don't mention the fuel filter, I am thinking that you have already changed it out???

Have you ruled out the fuel?? I have seen a 5 gal tank used to bypass the boats tank. Is in fogging fuel injected engine.

Please let us know what you find!!!

Author:  bryan9633 [ Fri Mar 18, 2011 6:09 pm ]
Post subject:  Re: 1994 OMC 5.0 EFI wont run below 1000 rpm

Thanks for the reply. Yes, I have replaced the fuel filter. I pulled the plugs last night after running it on the hose for a bit. They were covered in black soot. I would think mabey an injector was leaking if it was just one but they were all that way. I went ahead and put a new map sensor on it last night also. That seemed to help the idle drop down to 750rpm or so. It still runs alittle rough and I would like to be able to bring it down another 100 rpm. I have set the timming at 5 deg. btdc but I did it without a codemate or scan tool where I could disable the eec timing. My next step i feel is to find one of these products and set the timing again.

Author:  jvthundercat [ Sun Mar 20, 2011 8:06 am ]
Post subject:  Re: 1994 OMC 5.0 EFI wont run below 1000 rpm

Back to the basics first. Do you have even and enough compression in the cylinders?
You already did my first guess with the TPS, and even if the new one was bad, it most likely would not match those conditions. Maybe cutting power to the computer so that your new TPS resets.?

Author:  BoaterDan278 [ Mon Mar 21, 2011 5:43 pm ]
Post subject:  Re: 1994 OMC 5.0 EFI wont run below 1000 rpm

My understanding is that you pull a shorting bar in the wiring harness, to disable EEC when you are timing an engine like yours. Dan

Page 1 of 1 All times are UTC - 6 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/