Car does NOT want to start.

SON240sx Automotive
1

Alright, so yea car doesn’t start. Well it starts, but you need to cheat it with some air intake cleaner to get it to fire up. So when you get it running it’ll run terribly. Starts to chug in 3rd and 4th gear at 2500rpm. Figured it was the MAF, changed it, still does the same thing. Not too sure what else to check for. Checked for spark, fuel, compression is fine, checked grounds on the ECU, checked the ECU itself. Really not sure what other direction to go. If anyone could help it would be much appreciated. thanks.

2

Well I donno, If i was you I would think maf as well, I think mafs have a fail-safe that doesn’t let the car pass 2400 when its messed up. I have no ideas I’m just really bumping this for you. :slight_smile:

3

Check the MAF voltage at the ECU and at the plug

4

alright, so heres the update on what i’ve done so far. I’ve replaced the MAF but still getting the same thing. checked voltages from the MAF and the ECU, all fine, but no start. I’ve checked the diagnostic mode on the ECU and it gives me an ignition reference code. printed out a troubleshooter on mitchel 1, did all the tests STILL doesn’t start unless you cheat it. hooked up a scanner to the car, picked up the same iginition reference as well as a crank angle sensor code. tried using a different crank angle sensor, STILL won’t work. weird thing is, is that the codes will only appear periodically on the scanner. when the codes are cleared they may or may not show up. regularly, when you haven’t fixed the problem and clear the code, it should show up again. so now i’m starting to lean towards it being an ECU problem. still gotta run a couple more tests, but so far i’ve got bubkiss. any help with this will be much appreciated.

5

so i found the problem. i probed the the wires for the ecu power supply and turns out they were not getting enough voltage, so because of that it was in safe mode for some reason. jumped the wire directly to the battery and the car started up fine and runs great again. thats the fucked up thing about electrical. you can spend weeks troubleshooting and in the end it’s the simplest solution in the world. ah well, only way you’ll learn :stuck_out_tongue: . thanks for everyones input.