PDA

View Full Version : sr20det crank no start


Sr20probs
04-06-2020, 07:09 PM
hey guys i'm at a lost

I have a sr20det red top that cranks strong but wont start. it started right up before.

diaged as followed

good spark
good fuel pressure
good compression as its a brand new bottom end(ran great till it decided to just not fire)
it has air as I can read on tuner studio
im able to test the injectors through tuner studio all click nice and loud
full 12v
all grounds checked and replaced as needed
brand new wiring specialties harness
megasuirt pnp 2

NukeKS14
04-06-2020, 08:20 PM
Did you change anything between when it was running and now?

Put a timing light on it and verify your trigger angle (Ignition settings -> Ignition options/wheel decoder) Set it to fixed timing and 15 or 20 degrees so it doesn't try to change while you're cranking it. Once you verify timing and get the CAS locked down, make sure to change back to 'Use Table'. You'll need a second person for this.

if what you're saying above is true, it's most likely a timing issue.

Sr20probs
04-06-2020, 11:30 PM
i installed an innovate wideband with the LC-2 controller. that's it. I notice when I crank it it says ignition advance 8.0? and its set to 15. it was also set to fix timing. would that cause it to not start?

NukeKS14
04-07-2020, 05:18 AM
Have someone crank and put the timing light on it.

Sr20probs
04-07-2020, 06:48 AM
Okay thank you. How could it just jump timing? Everything’s brand new and it ran great a few day’s ago. I did a fuse box tuck and it started right up after that. Installed controller. No longer starts. Removed controller still nothing. I’ll try timing.

NukeKS14
04-07-2020, 11:28 AM
Did you connect the controller to your ecu? If so, how did you wire it in? Did you change any settings on your ecu/tune file? You didnt mention the wideband or any of that in your first post.

Car runs fine, change something, car doesnt run fine. Problem is related to the change you made.

We can only reply to the information you decide to share.


Megasquirt saves your tune file when you change it usually. Try rolling back your tune to before you made changes (if you did) and see if that works.

If you wired the wideband controller into your harness its possible you messed something up there too.

Sr20probs
04-07-2020, 02:50 PM
I did not wire int the controller it plugs in into the ecu. I haven’t plugged it in yet. I just reset the timing along with the cas and not it’s back firing like gun shots. Did it once before I reset the timing as well. I have the megasquirt set up properly as well. I read something about a connector behind the passenger head light for the injectors? Is that some bull or no?

NukeKS14
04-07-2020, 04:07 PM
If its backfiring it isnt set right.

Assuming you got the ecu from diypnp here is their instructions with pictures for setting your trigger angle.

http://www.megasquirtpnp.com/docs/mspnp_g2_nj8994_s13.php?isModel=1

I have no idea what you're talking about or read about injector connectors. Do you have a link?

Sr20probs
04-07-2020, 05:17 PM
UPDATE PROBLEM FOUND exhaust cam gear cracked and pin almost came out. It didn’t fully come out. Do you think I fucked my head or block, it still spins nice and free.

NukeKS14
04-07-2020, 06:53 PM
You can pull spark plugs and put a telescopic cam/boroscope down there and inspect the piston tops for valve contact... or you can replace the cam gear and verify valve timing then do a compression test. Cant say. Wouldnt venture to guess.

Sr20probs
04-08-2020, 05:30 AM
Turns out it was the cam itself. It cracked right where the dowel pin goes. Must of jumped a tooth? Going to what you said and hope for the best.