*NEED HELP* RB20det no spark!

ONLY for ADVANCED technical discussion about the 240sx!
DriftRebel
Posts: 11
Joined: Tue Sep 07, 2010 7:59 pm

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I was driving down the highway when suddenly my car shuts off randomly. I pull over and see smoke coming out from under my hood and i realize that my maf sensor harness was on my exhaust manifold and it burned/melted my harness. I also noticed that my fuel pump wasn't kicking on anymore (due to the maf wires)... I re-wired the 3 wires from the harness with new wire and but connectors (temporary) and now my fuel pump works normal and its making fuel pressure as i can see it on my fpr gauge, so i crank the engine for a while and it doesn't want to turn over and i hear a knocking noise coming from my ECU... now i have no spark at all!!
I looked around and i noticed that i had a blown fuse in the fuse box next the my battery. The fuse is the brown ENG CONT fuse and i believe its a 25 amp fuse (cant remember exactly and too lazy to go outside right now). I changed the fuse with a new one and still no spark BUT now my ECU isn't making the knocking noise anymore either... i checked my coils to see if they are getting power and there is NO power going to my coils..

Is it possible that if the MAF sensor is bad; the engine wont get any spark?...
Is there a way i can check my ignitor pack? I also read that it can be my CAS position but im not sure how that would jump out of place...

ANY HELP is GREATLY appreciated cause im stuck and i NEED my car ASAP!!

THANKS!!


DriftRebel
Posts: 11
Joined: Tue Sep 07, 2010 7:59 pm

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...and is it possible for the ECU to have blown/fry when the MAF harness melted?... could this have caused a short in the circuit and mess up the ECU?

IBustV8s
Posts: 15
Joined: Thu Jan 27, 2011 6:12 pm
Car: 1992 240sx

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well im not shore if it could have fried the ecu, and also im not shore if it would make your maf go bad, but i do know how to check your coils. just unplug your coils and take a multimeter and stick the leads to the prongs of the coil it doesnt matter which ones u hook the leads to if its backwards it will just read negative so many ohms of resistence. if it does then just ignore the negative symbol. set your meter to ohms and if it reads O L then u have an open somwhere in your coil wiring. and it would help to pull a spark plug leave it attached to the wire ground the spark plug its self to a piece of metal, turn the engine over and see if it is sparking. hope this helps and sorry i didnt know the other stuff.

DriftRebel
Posts: 11
Joined: Tue Sep 07, 2010 7:59 pm

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Thanks ^^ but i already checked the coils and they are not getting power.....

I manually turned my CAS with my key on the "ON" position and my fuel injectors were NOT getting any fuel and it is STILL NOT getting any spark... Now im pretty sure that when you Manually turn the CAS, the ECU thinks that the engine is running so it sends fuel to the injectors and spark to the coils so now my guess is that i have a bad CAS or my ECU is all messed up.. Or worse than that, my wiring is all jacked up! I hate wiring!!

But anyways, i need some help trying to test my CAS a different way than manually turning it cause i need to see if i should get a new one from somewhere. I dont know anyone else that has a RB20DET and so i cant just plug my CAS into another car to see if it works so i need an alternative

Thanks
ANY HELP would be aswesome!!

IBustV8s
Posts: 15
Joined: Thu Jan 27, 2011 6:12 pm
Car: 1992 240sx

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man i dont know much about rb series engines but i do know that manually turning the cam sensor on an sr all your doing is adjusting timing and i dont think your maf will cause you not to get any spark. but if u wanted u could check for a open in your maf wires. and if your not getting any fuel you could jump your fuel pump to a 12 volt source. man youve just about got me stumped im not shore how to narrow it down sorry hope u can figure it out. if i think of somthing else ill post it

DriftRebel
Posts: 11
Joined: Tue Sep 07, 2010 7:59 pm

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im working this entire week so i dont have much time to work on it but ill try to get some stuff done on it soon.. Thanks

DriftRebel
Posts: 11
Joined: Tue Sep 07, 2010 7:59 pm

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just figured it out today. My ecu "Power Supply (Engine Control Module)" pinout was fried.. so i soldered it up and its good to go. Im soo stoked that its back up and running and the best part is that it was FREE haha


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