Page 1 of 1

Noob ?'s - replaced engine, car cranks but won't fire

Posted: Mon Jun 19, 2023 7:35 am
by sgmineha
Hey guys, forgive my ignorance here, but looking for some help on what is/is not normal. I built my supercharged k20a2 powered racecar a little over 3 years ago and had zero issues getting it running. I wired everything by the book and it started on first attempt, got it tuned and it has been running great with no issues. Unfortunately I had an overheating event that led to a cracked ring and some scoring on the cylinder, which led me to getting the motor replaced. New motor has a stock k20a2 bottom end with a built head (but not by me). I put the new motor in and everything back together and cannot get it to fire. I am a car guy but don't really know what I'm looking at when it comes to KManager data, so wanted to share what I see and hope you guys can make sense if it is normal or not. Car did sit for about a year from pulling the old motor out and putting the new one in. I replaced the fuel, cleaned/tested injectors, battery, spark plugs, and have tried both with the coil packs that came on the new motor as well as swapped the old ones off my old motor.

-All sensors appear to be reading data properly except the only sensor data I see that looks out of place but I am not certain of is the CAM sensor reading. This is reading a steady 107 degrees while I am cranking the motor (0 while not). Is this normal, expected, or flat out wrong? What should I expect to see while cranking and what might this indicate (bad sensor, wiring, or timing issue or...)? I did make sure the CAM sensors plugs were connected to the proper sensor according to my wiring diagram, although these are the sensors that came with the new motor and not the ones from my old motor that was running. I am getting RPM's so crankshaft sensor should be working. CAMCMD says 0 degrees, if that is helpful at all.

TLDR:
*Replaced engine (same harness as when it was running)
*New fuel, battery, spark plugs, coil packs, had injectors cleaned and tested
*The car has fuel pressure, and is getting fuel
*Tested voltage and grounds in MANY places and everything I have checked seems to check out
*CAM sensor reading is steady 107 degrees while cranking <- Is this normal?

Thanks in advance for your help and appreciate your patience with a noob!

Re: Noob ?'s - replaced engine, car cranks but won't fire

Posted: Mon Jun 19, 2023 7:50 am
by sgmineha
Other piece of data - BATT drops to ~9V while cranking - I assumed this was normal but sharing just in case that helps

Re: Noob ?'s - replaced engine, car cranks but won't fire

Posted: Mon Jun 19, 2023 9:23 am
by Spunkster
Have you tried the ECU on a known running vehicle? It sounds like it could be a mechanical issue on the new engine.

Re: Noob ?'s - replaced engine, car cranks but won't fire

Posted: Mon Jun 19, 2023 4:00 pm
by sgmineha
It's the same ECU as when it ran before. Right now looking for clarification on what to expect from the CAM sensor while cranking.

Re: Noob ?'s - replaced engine, car cranks but won't fire

Posted: Mon Jun 19, 2023 4:34 pm
by Spunkster
You should try the ECU on a known running vehicle as it sounds like a mechanical timing issue on the engine.

This will tell you immediately if the issue is with the ECU or with your engine/wiring.