Crank no Start

[Scott Beckett]

Thanks for reading this.

I just got do a nearly Identical swap as outlined in this thread: https://shoforum.com/index.php?threads/2010-to-2015-sho-engine-swap.131474/page-3

Everything went well, as far as bolting up. sensors coils, ect. I ham getting a no start condition. I took a coil off and checked for spark using a screw driver to the valve cover, no spark. So I checked another one, same, no spark.

I have my scanner attached and am reading rpm from CPS. What else could cause a no spark situation.

I have fuel getting to the fuel rail

 

[Scott Beckett]

Forgot to add, NO CEL either

 

[krewat]

Check for +12V to the coils. You might have blown a fuse. The PCM will ground one side of the coil to charge it, then disconnect it and the magnetic field collapsing in the coil creates the spark. If there's no +12V on the other side of the coil, it won't fire.

 

[Scott Beckett]

I was thinking about that, but last night it was getting too dark and I've been working on the car all day long. I figured I would check that first off to day when I get off of work. Thank you and I'll let you know what I find

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[Scott Beckett]

So did some testing I have 12 volts at the coils, is there any kind of fusible links in the wiring harness for the coils? For the negative side

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[Scott Beckett]

I also would assume that if I hurt my test light up to positive on the battery and then stuck the Probe on the ground side of the ignition coil plug it should switch while I'm cranking. And it just stays dark

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[shaker281]

I doubt very much there would be a fusible link on the negative/ground input to the coil packs. If you are not seeing the ground signal to the coil packs then you need to look at the ignition schematic for the required inputs to the PCM that are necessary to put GRD out on the low voltage coil wires. Then you will know which connectors, pins and wires to chase for these inputs. Sounds like you have ruled out the CPS. How about the cam position sensor (might be called a 'VCT' sensor on our cars)?

As you have swapped engines, it seems likely you have a sensor not connected or a problem with a connector (not fully seated?) or pinched harness wire feeding the PCM.

I do not have the schematic, so I am simply applying basic troubleshooting here.

 

[Scott Beckett]

I certainly would be thinking that since the engine I took out was mostly running (spun main), that I would have simply forgot to plug something in or not hook something up properly. I went over it with a fine-tooth comb last night, couldn't find a single connector that was loose all my grounds are hooked up couldn't find anything at all unplugged.

I am pretty sure that the cam sensors are working as well, but I only based at off of the Cam and crank sync PID on my scanner states that they are in sync.

I am going to attempt to get a wiring schematic for that circuitry tonight, wish me luck.

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[krewat]

The COPs are grounded by the PCM, so you won't see a "ground" when the engine isn't running. However, if the PCM can't complete the circuit, that will cause the COPs to not fire. But then, you didn't disturb the PCM so that should gounded, and the starter is working, so the engine is grounded. Is it possible you missed another engine ground?

What you can do is take a digital volt meter (not a test light), set to AC volts, and connect both probes to the crank position sensor and crank the engine. Even with the key off (if you jump the starter solenoid), you should see something like .1-.3 volts or maybe even more while cranking. The same goes for the cam position sensors, but the pulses will be much further apart, and the volt meter might show less voltage but it's worth a try.

 

[shaker281]

To be faiaaar (Letterkenny anyone?), the best way to check the CkPS amd CmPS would be with an O-scope. Should see nice regular square waves! Could be a sensor, but smells like a connectivity trouble.

 

[Scott Beckett]

I just subscribed to alldatadiy, mainly for schematics, so I will keep you updated

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[rubydist]

just because there is no check engine light, that doesn't mean anything. please pull codes and let us know what you find.

 

[SHOdded]

What year/model is your vehicle again? A 2010-12 SHO or is it a Flex/MKT, or ...?

Here is some basic info on a 2013 SHO ignition system. Will be a little different from 2010-12 but same concepts.

 

[Scott Beckett]

What year/model is your vehicle again? A 2010-12 SHO or is it a Flex/MKT, or ...?

Here is some basic info on a 2013 SHO ignition system. Will be a little different from 2010-12 but same concepts.

2010 flex

There there are some codes in it, but if memory serves I don't think they could be related to a no start situation, and I believe they were all there before the engine swap anyway. But I will post them just in case you see guys see something that I didn't. It will be early afternoon before I'm back at home.

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[Scott Beckett]

Last night I check continuity on all of the coil ground wires back to the PCM, the harness is good. All the way to the plug to the PCM. So that means the PCM is not grounding the coils either on purpose or at fault.

Is it possible that I could have damaged the PCM when I had the wiring harness disconnected but had to put the battery back in it to turn the ignition on in order to get the car out of park to push it out of the garage for my crane?

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[SHOdded]

I don't see how that would have damaged the PCM if that's all you did. But it is worth checking the coil drivers in the PCM just to be sure.

 

[Scott Beckett]

I don't see how that would have damaged the PCM if that's all you did. But it is worth checking the coil drivers in the PCM just to be sure.

How would I go about checking those coil drivers?

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[krewat]

Check that you're getting a signal from the CPS first.

 

[Scott Beckett]

Check that you're getting a signal from the CPS first.

It is registering 294-304 rpm while cranking

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[SHOdded]

Working fine then as diags state the RPM needs to be > 150