What sensors will prevent *update post 7* turns but backfires now

[Svtfreak]

Car started and ran fine. Took motor out to change converter. Reinstalled. Turned over but didn’t start. Then stopped turning over. Fuel pump runs, supply to all injectors and coils goes to +12 when key is on. No codes thrown. The only thing I haven’t verified that I can think of is the neutral safety switch in the trans but not sure it works like on/off. It might be on the canbus and be a little more complicated but working on finding out. Checked the starter relay and fuse (actually swapped with fuel relay as it’s known good). The ngauge device communicates good with the ecu. It sees rpms when I did manage to get it to turn over once (I was not able to get my test light on injector or coil, it stopped turning over again). It seems as though I have a pin not making good contact with a needed sensor for the ecu to send start signal.

When I first installed, it did same thing. Wouldn’t send start signal to the starter. It was the crank position sensor was unplugged. I did check it this time, even pulled it and cleaned and reinstalled to make sure I didn’t bump and break it. It looks fine. Is there a way to test it? Maybe a ohm meter and putting near metal?

Anyway, what other things will trip the computer to not allowing a start signal to go to the starter? Anyone have any other input? It’s a gen 2 coyote with frpp controls pack and 6r80 auto.

[Railroad]

Sounds like something simple, ign switch?

[edwardb]

I'm assuming you checked and there's +12V on the SMR wire in the Coyote harness when the key is in the start position? Pretty basic question but you didn't mention it. Curious if it would start and run by applying +12V directly to the starter solenoid. A little risky perhaps, but maybe could confirm it's just the starting circuit and nothing else. Ignore that suggestion if you think it's a really bad idea.

[Svtfreak]

Railroad, I’m sure it is something simple. But I did check the ignition switch and it was fine. Sending 12v to the ecu when turned to start. I can also hear another relay that goes live when in start clicking.

Edward, if you mean the starter lead to the starter, it is not going to +12. That’s the problem. 12v on the starter will turn the motor over. But The ecu is not sending the signal to the starter on the starter lead when the key goes to start position.

[edwardb]

Railroad, I’m sure it is something simple. But I did check the ignition switch and it was fine. Sending 12v to the ecu when turned to start. I can also hear another relay that goes live when in start clicking.

Edward, if you mean the starter lead to the starter, it is not going to +12. That’s the problem. 12v on the starter will turn the motor over. But The ecu is not sending the signal to the starter on the starter lead when the key goes to start position.

I understood your question and no, that's not what I meant. SMR = Starter Motor Request which is the Light Blue wire in the Coyote control pack pigtail harness that needs +12V from the ignition switch to trigger the start sequence in the PCM. I was just asking whether you checked if you were sending this +12V signal. Your answer to Railroad confirmed that.

[Svtfreak]

I understood your question and no, that's not what I meant. SMR = Starter Motor Request which is the Light Blue wire in the Coyote control pack pigtail harness that needs +12V from the ignition switch to trigger the start sequence in the PCM. I was just asking whether you checked if you were sending this +12V signal. Your answer to Railroad confirmed that.

Ah! Ok Edward. I misunderstood which wire then without being there looking at it

Yes, the smr wire is getting power at the ignition switch. But, since you bring it up, I may track it down at the ecu and make sure it’s getting there. The simple stuff is checked so time to start looking at the more off the wall possibilities.

Side note, I woke up at midnight and it dawned on me that I forgot to tighten the motor mount nuts. Maybe God was looking out for me and when I tighten those up tomorrow, it’ll fire right up lol!

[Svtfreak]

Ok. I loaded the factory tune up and it turns over. Tried to hit but backfires. Loaded the supercharger tune (since it should start easier) and it still is backfiring and won’t start. I’m happy it’s better but any ideas on why that?

[Svtfreak]

Got it! Guess it just needed to turn over a few times. She’s all fired up! And I can stop the back wheels with the brakes. It takes some leg on jack stands but it stops. Next day off (might be after my 7 nights) I’m gonna put it on the ground and go see how it acts in the street.

[David Hodgkins]

Video!

:)

PS What do you mean it "Takes Some Leg" to stop it on stands? Are the brakes bled?

[Svtfreak]

Video!

:)

PS What do you mean it "Takes Some Leg" to stop it on stands? Are the brakes bled?

I’ll have to get a new video.

It takes a bit more force than i think it should. Yes I’m gonna bleed the brakes good again and make sure they are working to 100%. But I’m also curious how much it’s gonna take once it’s on the ground and have tires on the ground and fronts stopping it.

[Svtfreak]

Video!

:)

PS What do you mean it "Takes Some Leg" to stop it on stands? Are the brakes bled?

This is first start cold after sitting all night. And rhe KAM’s still prolly have some learning to do. I’m pleased so far. Next day off (mid next week or so) I’ll clean all the crap out the inside and go for a ride.

https://i.imgur.com/ReIXOXB.mp4

Sounds works on imgur so maybe try this link
https://i.imgur.com/ReIXOXB.mp4