Rb20 Wierd Missfire

[gelousi]

Hey every just finished my conversion yesterday and finally got it runnig. The story is the motor came out of a s13 so it was ready to go back in well it was just the mounts none of the wiring was done. I did the wiring which was fairly easy 2 wires ign one ecu memory and other is fuel pump everything else works fine. Now when i start it idles perfect can give it a few good revs for about 1-2mins and then it starts missing and wont go away. Ive changed eng loom tried 2 ignition modules 2 afms replaced coilpacks new spark plugs and changed o2 sensor. The only thing that i can think of is that i opend the ecu and found a burnt track, repaird that by soldering a wire and tested the track working perfectly could something else in the ecu be faulty? it also doesnt have the cold start valve so the hoses are just blocked for now. its really doing my head in and if anyone has an ideas would be a great help

Edited May 14, 2010 by gelousi

[gelousi]

also the ecu light stays on after i turn the car off i have no idea why

[Curmi]

ecu is telling you there is a problem run a ecu diagnostic witch makes the ecu flash so many times eg 5 and number 5 is your problem. if that makes sense search on google for it.

try resetting your ecu first.

[gelousi]

just done it all i got was 55, all ok so very strainge that the ecu is saying all ok but the car runs on 5 cylinders constantly = ecu fried?

[gelousi]

anyone else experience this?, i spoke to a mate he rekons i need to run a ign wire to power the coilpacks as they might not be getting full power which is strange because ive gone off the factory wires on the loom which are, black/red and white both joind to the black/red on the s13 loom which is factory ign, then ive got my white/black going to the factory red which is ecu backup i have read nothing at all about adding another ign wire to coilpacks if i was to give it a shot where to the coilpacks get power from is it the 3 pin plug near the ign module? thx

[geraus]

Could be many things when it comes to miss firing, you can try clean your AFM with CRC contact cleaner.

Also check the injectors and wires that gose into each injectors, or take to the mechanics and do some

fuel pressure test ! There are many variable for the miss firing problem. Best way is to start from something

easy and work you way up... or try

check earths. main one from engine.a mates did the same idled fine but as soon as you reved it up missed like a bitch. we found the earth lead from block to chassis rail corroded and fricked. changed it and after it was sweet. run a jump lead or thick wire from engine to good earth point on chassis or even better still battery to check.

Hope this helps good luck!

[gelousi]

FIXED! was getting 15v from the alternator :S nowere in the conversion guide does it tell you to use the origional ca18 alternator loom there is one plug that is wrong. Ahhh the beuatifull power of a rb20 in a s13 its amazing!!!!!