502 mag mpi missing under load???
02-25-2003 | 09:23 AM
#11
Charter Member # 90
Joined: Oct 2000
Posts: 199
Likes: 1
From: Montgomery, Al
Liquid,
Hopefully the new wires will solve your problem. In the case they do not, you may want to replace the knock sensor. I had very similiar complications a year ago and it ended up being the knock sensor. It is on the starboard side, right by the block drain plug.
-Mark
Hopefully the new wires will solve your problem. In the case they do not, you may want to replace the knock sensor. I had very similiar complications a year ago and it ended up being the knock sensor. It is on the starboard side, right by the block drain plug.
-Mark
02-25-2003 | 05:20 PM
#12
Platinum Member
Joined: Mar 2001
Posts: 420
Likes: 7
From: Table Rock Lake, MO
My boat is a 98 Baja 25 Outlaw 502
Let me start by saying that I am in no way an expert on the subject, nor do I claim to be. As far as coloring of plugs, I do know that there have been threads in the past about them, so a search may help more than me. Also, keep in mind that with todays clean unleaded fuels, it isn't as easy to tell plug readings as it used to be. Here's the deal, and I will tell you wide differences. Some people can tell where the heat line is on the ground strap, I have never been that sure of myself. If the plug is black all over (it seems to be natural for the base below the threads to be black), I am talking the ground strap and insulator, you are rich. If the insulator is clean and the ground strap is white and looks like it has blisters (and chalky) you are lean. I like a tan-ish color on the insulator and grey to no color on the ground strap.
Anyone with other input on this would be great.
I am not trying to tell you not to change your computer. I am just saying that I wish I had not done it all at once. That way I would have been able to tell which change did what. I am sure (at least since I spent the $) that the remap helped me, but I had also added the adj. fuel press. reg. and so with that I could have asjusted for being too lean without the remap. It is my understanding that with the proper progamming you do not need to change the fuel pressure. Just make sure you get it remapped right. I would never have thought twice about checking the pluge after I changed the computer if I had not changed the fuel regulator. It was in trying to get that dialed in that I found my lean condition. Let me put it this way, I had to run around 46 psi when stock is around 36 with my first remapping. Now I run at the stock pressure.
Feel free to ask any other questions.
Bill
Let me start by saying that I am in no way an expert on the subject, nor do I claim to be. As far as coloring of plugs, I do know that there have been threads in the past about them, so a search may help more than me. Also, keep in mind that with todays clean unleaded fuels, it isn't as easy to tell plug readings as it used to be. Here's the deal, and I will tell you wide differences. Some people can tell where the heat line is on the ground strap, I have never been that sure of myself. If the plug is black all over (it seems to be natural for the base below the threads to be black), I am talking the ground strap and insulator, you are rich. If the insulator is clean and the ground strap is white and looks like it has blisters (and chalky) you are lean. I like a tan-ish color on the insulator and grey to no color on the ground strap.
Anyone with other input on this would be great.
I am not trying to tell you not to change your computer. I am just saying that I wish I had not done it all at once. That way I would have been able to tell which change did what. I am sure (at least since I spent the $) that the remap helped me, but I had also added the adj. fuel press. reg. and so with that I could have asjusted for being too lean without the remap. It is my understanding that with the proper progamming you do not need to change the fuel pressure. Just make sure you get it remapped right. I would never have thought twice about checking the pluge after I changed the computer if I had not changed the fuel regulator. It was in trying to get that dialed in that I found my lean condition. Let me put it this way, I had to run around 46 psi when stock is around 36 with my first remapping. Now I run at the stock pressure.
Feel free to ask any other questions.
Bill
