DPFI-MPFI problem
 

OK. Did an mpfi swap a while back. When I first finished the swap, it ran limp mode, redlining at 3200. Messed with some wires for a while and made it work. Then I took out the ecu to try it on someone else's car and when I put it back in it was running limp again. I have re-wired everything and it's all perfect by the book. Throws a code 4 (Crank Position Sensor). Anyone ever experienced this? I don't know what I did to fix it the first time...

Thanks for any help

Rich

Re:DPFI-MPFI problem
 

look at the 2 wires u had to add running from the dist. make shure u reset the ecu after u make changes.

Re:DPFI-MPFI problem
 

Definately already did that. All of the wires are correct. I think it's probably the distributor, but I can't understand why it worked for a while and it's not working again. I have heard of people having this problem before, and I think I'm just concentrating too hard on it. Someone give me a solution please! :) thanks in advance

Re:DPFI-MPFI problem
 

most likely you have the wires swapped for the crank angle. happens all the time

Re:DPFI-MPFI problem
 

when you put the new wires in at c1 and c2 on the ecu and ran them to the dizzy..what did you do with the wires that were still there. check and make sure that c1 is at b10 and c2 is at b12. thats the new crank angle sensor spot i think. i messed that up and my car ran in limp mode for a lwhile till i fixed it

Re:DPFI-MPFI problem
 

Yes, I definately switched those wires to their correct positions. Does anyone know if one of the crank wires and one of the cam wires go to ground? I'm looking at the shop manual and it looks like one of the wires runs to ground in addition to the computer. Maybe my ground is loose.

Re:DPFI-MPFI problem
 

recheck your grounds, try another distributor, check for any frayed wires.

open up the dizzy, and check for any frayed wires.

check for any loose wires that were changed in the swap, check for any loose connections in the plugs.

Re:DPFI-MPFI problem
 

i dont have those wires grounded on my car(the 2 u add from the dist. to the ecu). runs fine. i have done one swap where i did ground them and a couple where i didnt . dosent seem to madder. :-\

Re:DPFI-MPFI problem
 

I have the same fucken problem right now. I just put a minime in my 88 dx and the damn thing doesnt rev pass 3200. someone please find a solution.

Re:DPFI-MPFI problem
 

what site did you follow?

Re:DPFI-MPFI problem
 

I redid my connections to the distributer today and I used my friends chipped ecu for a B-series and it worked but it pings at the lower rpm. But when I plug in the other ecu which is a vx it doesn't rev again. I'm figuring that is this shitty ass ecu which I am going to get chipped. I don't know-what you guys think?

Re:DPFI-MPFI problem
 

how did you connect the wires?

soldering i hope

Re:DPFI-MPFI problem
 

this is hmt buddy, nothing is guaranteed.

Re:DPFI-MPFI problem
 

Even twisting wires together by hand and letting them lay there on the floor and get loose huh ;)

Re:DPFI-MPFI problem
 

when i first did my mpfi swap, i had the same problem. Code 4, and the 3200 rpm rev limit. Turns out, the two extra wires i had to run were reversed...so i switched em around and reset the ecu....voila...no code, no limiter ;D Believe it or not, there is a polarity so to speak to those wires. I just got rid of my code 9 today by doing the same thing.