ok so i swap my auto trans for a manual one on my 2002 elantra and now the car wont start it will crank but wont run on its own i have tryed with both auto harness which is still in car and with manual harness, both ecm auto and manual and i dont know what is wrong and hoping someone could have the answer to my problem.

 

cranks/won't start always makes me think Crank Position Sensor first - and you've been fooling around with the wiring in the engine bay. Check that the crank sensor is in a CLEAN hole and the wires are in good condition. That, or you've overlooked a signal somewhere. The voices tell me I had to bypass a switch that was formerly on my automatic's shifter base, but I don't recall for what and it's a different platform from your car anyway.

 

I have checked all the sensors and wires and there all good and I've gone over the harness a dozen times and everything is connected properly as I labeled them as I took them off and for there with you have to bypass the transfer axle range switch so the car thinks it's in neutral or pack to Let it start

 

Start simple. Check to see if you have spark and fuel out of the injectors. You know the motor cranks but do you know it is firing or receiving signal to fire the injectors?



Only so many options that can be wrong. If you are assuming the sensors are all good then I would guess the ECU is deciding it doesn't want to play.

 

OK update my cousin was over and we were testing some things the car has No spark and the fuel pump is not coming on after playing around with the volt meter and testing some things my cousin believes that the relay for the fuel pump isn't getting enough power to turn it on as in only reading 5 volts and not 12 but we don't know if that's how it's suppose to be

 

Jump 12V to it and see what happens? This is where troubleshooting diagrams on hyundaitechinfo will be your friend, if they exist. Nevermind that you did any work, approach it as a fresh problem. Examine the symptoms only, not what you did - because it is what it is, no matter what was done. If you troubleshoot it right, you'll end up with a working car.

 

If you jump it it comes on like it's suppose to and I have print out all the diagrams off all data and hyundaitechinfo as Well so I can travel and go over Eventing tomorrow with my cousin I'm just surprise that this didn't work all parts were off a working doner car and and auto.trans items were switched for manual which are the trans linkage clutch slave cylinder axles starter and ecu the harness is still an auto harness but even with Manuel harness it still has same problem

 

I wonder if the Auto ECU and TCU provided some type of signal together to power the coils and fuel pump?

 

That wouldn't explain y with a Manuel harness and ecm it still has the same problem

 

Well the coils and fuel pump are powered from the engine bay fuse box so start looking there, they both getting their accessory power from the main relay. Try swapping it for a new one.



I understand you replaced the auto harness with a manual one but unless you took the engine bay fuse box from the donor vehicle there may be differences with the ECU communicating with it and the behind dash fuse box.