No pulse on injectors and ignition coils. Help!!

SlipperySnake

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$200 not bad at all. I tried the pats bypass tune and didn't change. Pcm was supposed to be here Friday but now Monday due to the train it was on being derailed.


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hotcobra03

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Update new pcm made no change. Pulling harness to inspect all signal wires and harness itself.
I would recheck crank sensor before pulling everything. .

Odds are if a wire it should be in engine bay.vs body..

We just a squirrel eat a harness in our tundra..ate 14 of 36 wires in a harness hard to reach..



If me I pull crank sensor and hand test signal out put..than check at main engine connector c133..

continuity test ..you did get a 0 on both wires with no reading on all other pins in connector?
 

SlipperySnake

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I would recheck crank sensor before pulling everything. .

Odds are if a wire it should be in engine bay.vs body..

We just a squirrel eat a harness in our tundra..ate 14 of 36 wires in a harness hard to reach..



If me I pull crank sensor and hand test signal out put..than check at main engine connector c133..

continuity test ..you did get a 0 on both wires with no reading on all other pins in connector?

Ya I've tried all that man. Tested everything I can, all good.


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hotcobra03

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Motor is brand new and built so yes it has been off but it was timed correctly i was there. Even if it was off a tooth or two it would send a pulse to the injectors and ignition coils.


If trigger/pulse wheel isn't there..

It wouldn't be the 1st thread I've seen where this piece was forgotten
 

hotcobra03

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What about ground for pcm?
Looking at wiring diagram..I see 2 ground wires going to g104..

If reading right these ground coil and injectors.
1 for each bank..

G104 is on radiator support.I recall reading there is a connector along fender behind battery toward fusee box..

You did check all this?
 

SlipperySnake

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Okay so update, I got the motor running. I pulled the entire harness of the car and checked everything, all was good. I put a cup under an injector and got fuel while cranking. So I assumed i was getting pulse. Went to test for a spark with an inline spark plug test and it worked...So maybe a wire as pinched or something, I honestly don't know. I also turned the fuel pressure down to 20psi vs. before 40psi. So now I have something even weirder going on. The motor runs rough and tons of black smoke, like I can't even run the motor for 15 seconds or more, because it smogs out the garage and I can't even breathe. Either the motor is off a tooth or a couple, but even if it was off a tooth or too it wouldn't have this much fuel and hot box me out of the garage. Inside of the downpipes are wet and black, it backfires like a mother and runs rough. It's getting very flooded is what I'm assuming. Now the really weird thing is the gauge cluster is active when I turn the key on, displays miles and the aeroforce scan gauges display given sensor information. I start the motor and as soon as its running the gauge cluster odometer displays "------" instead of the mileage prior to starting. The aeroforce scan gauges also don't communicate with the pcm and the rpm gauge isn't up at idle rpm's. So I'm basically lost and not sure what's going on here lol. Screw this car, it's been hell and now right when I'm in the final stretch she gives me all these problems.
 

hotcobra03

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Timing off a tooth would be a valve getting bent..

Intake /exhaust cams backwards could be something. .

Sorry to hear it's a tester of patience. .

Best thing to learn on tho
 

MG0h3

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Put your fuel pressure back where it's supposed to be.


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03SonicVert

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Dashes mean the PCM is going offline from the cluster due to the PCM shutting off or the network going down/shorting out. I believe 914/915 is the network the PCM and cluster communicate via. If V-Ref is shorted to ground it will shut the PCM down. Check for 5V at the MAF, TPS, DPFE, Fuel Tank PSI Sensor, etc. Don't have my EVTM handy but check where V-Ref goes. I've seen where MAF wires were extended and swapped, Fuel Systems redone where the Fuel Tank PSI Transducer wiring was swapped, etc.

KOEO are there dashes? If the mileage is shown then data log KOEO and see what TPS voltage does when you depress the throttle (0.9 closed, nice slope up to 4.5 WOT), Fuel Tank PSI should read 2.5V with no PSI or Vacuum (Fuel Cap off), MAF close to 0V KOEO. Look for things out of line.

Highly doubt base engine timing but you could do a wet compression test to get an idea or a leakdown.

I'd bet there is a wiring concern still. Use either a volt meter to do voltage drop testing on the PCM powers & Grounds or at least use a brake light bulb to load test the powers and grounds. No LED lights or DVOM only. You may have a weak power/ground showing voltage, pass resistance testing but not be able to carry the load. Either at the Fuel Tank PSI Sensor wiring, FPDM or on the engine/body tuck areas. Mechanical/base engine gremlins should not cause "no communication" or interm issues. Unplug any other modules on the network besides the PCM and Cluster. Check 914/915 with KOEO for shorts to ground, shorts to power or shorted to each other. If you have short to power start pulling fuses to isolate/identify responsible circuit.

Stay after it and you'll get it. If it's not your daily then don't be afraid to take breaks or walk away for a few days. Wish I was closer. My dad was a TV Repair Man! Had a gnarly set of tools and could fix anything! (If you don't get the reference Google it and watch the whole movie!)

TC
 

SlipperySnake

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Dashes mean the PCM is going offline from the cluster due to the PCM shutting off or the network going down/shorting out. I believe 914/915 is the network the PCM and cluster communicate via. If V-Ref is shorted to ground it will shut the PCM down. Check for 5V at the MAF, TPS, DPFE, Fuel Tank PSI Sensor, etc. Don't have my EVTM handy but check where V-Ref goes. I've seen where MAF wires were extended and swapped, Fuel Systems redone where the Fuel Tank PSI Transducer wiring was swapped, etc.

KOEO are there dashes? If the mileage is shown then data log KOEO and see what TPS voltage does when you depress the throttle (0.9 closed, nice slope up to 4.5 WOT), Fuel Tank PSI should read 2.5V with no PSI or Vacuum (Fuel Cap off), MAF close to 0V KOEO. Look for things out of line.

Highly doubt base engine timing but you could do a wet compression test to get an idea or a leakdown.

I'd bet there is a wiring concern still. Use either a volt meter to do voltage drop testing on the PCM powers & Grounds or at least use a brake light bulb to load test the powers and grounds. No LED lights or DVOM only. You may have a weak power/ground showing voltage, pass resistance testing but not be able to carry the load. Either at the Fuel Tank PSI Sensor wiring, FPDM or on the engine/body tuck areas. Mechanical/base engine gremlins should not cause "no communication" or interm issues. Unplug any other modules on the network besides the PCM and Cluster. Check 914/915 with KOEO for shorts to ground, shorts to power or shorted to each other. If you have short to power start pulling fuses to isolate/identify responsible circuit.

Stay after it and you'll get it. If it's not your daily then don't be afraid to take breaks or walk away for a few days. Wish I was closer. My dad was a TV Repair Man! Had a gnarly set of tools and could fix anything! (If you don't get the reference Google it and watch the whole movie!)

TC

Really appreciate this, kind of information I've been looking for. The odometer with key on engine off displays mileage, once the key is in run and engine is on mileage displays dashes. I was doing some reading and thinking maybe a pcm relay or ignition switch? What are your thoughts on this because all I can find online is this issue with key on but no while the motor is actually running.


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