You're seeing good waveform, and spark... and keep messing with spark stuff. Have you tried starting fluid?
P0320 dead on road
- Thread starter 4BY4ADV
- Start date
At this point I’d be treating this like a no start. Rent a noid light from Autozone and verify injector control. Verify fuel pressure. Try spraying starter fluid.
And yes, I suppose this could be a timing thing, maybe you jumped a tooth? Although it’s odd that it’s throwing the P0320. But you’ve chased that code to hell and back. Make sure everything is there for it to start and then chase timing.
Also… not sure how comfortable you are with that power probe, so don’t take this as an insult. Those things are awesome, but man are they dangerous in the wrong hands. Accidentally shooting battery voltage to the wrong circuit can fry the PCM real quick.
And yes, I suppose this could be a timing thing, maybe you jumped a tooth? Although it’s odd that it’s throwing the P0320. But you’ve chased that code to hell and back. Make sure everything is there for it to start and then chase timing.
Also… not sure how comfortable you are with that power probe, so don’t take this as an insult. Those things are awesome, but man are they dangerous in the wrong hands. Accidentally shooting battery voltage to the wrong circuit can fry the PCM real quick.
Not going to rule it out, but how likely am I to jump a tooth on a fully remanufactured engine with new timing chain/etc? (ATK engine, replaced August/23 and two years left on warranty).
No insults taken, I'm pretty versed in electronics/electrical components. Definitely not injecting power into places that it shouldn't be!
Yeah there’s a whole host of reasons I’m not convinced it’s jumped a tooth. Which is why I’d be treating this no start as a blessing. You find what’s causing the no start, you’ll find your problem. So long as you haven’t injected power where power ought not be along this process
Have you verified that your plugs aren’t just soaked from all the cranking?
I'm only cranking for short periods with a long time between tests for that reason. When I did pull a plug at one point, it was looking pretty good. Actually, come to think of it, if it wasn't starting, it should have at least been a little wet from fuel right? I don't remember it smelling like fuel.
Since I have fuel pressure at the rail, I'll go straight to testing the injectors next.
Since I have fuel pressure at the rail, I'll go straight to testing the injectors next.
Or hell a screwdriver against an injector and the other end to an ear and listen for clicking.
Or spray a little go juice down the yap.
-Mac
Or spray a little go juice down the yap.
-Mac
Noid light flashing and have fuel pressure. Also smells like fuel.
Back to spark. Here’s where things are falling apart.
Cap and rotor look good/clean.
Timing light… WTF. Very dim and SLOW flashes. For a 2-3 second crank, I have maybe two flashes and not bright like I remember when I used to work on my Bronco in high school.
Switch to coil wire, more flashes but not a crazy strobe like I’d expect. Wanting to rule out the timing light (brand new), I put the inline spark plug tester back in on cylinder one. It has these very weak pulses then a brighter flash… then weak pulses on repeat. So if I’m only looking at the bright flashes, I’m not getting much spark.
I’ve swapped coil, camshaft position sensor, cap and rotor look great. Spark plug wires are… maybe 6 months old, so I’d hesitate to think that’s the issue.
Does this point back to distributor or a computer issue?
Back to spark. Here’s where things are falling apart.
Cap and rotor look good/clean.
Timing light… WTF. Very dim and SLOW flashes. For a 2-3 second crank, I have maybe two flashes and not bright like I remember when I used to work on my Bronco in high school.
Switch to coil wire, more flashes but not a crazy strobe like I’d expect. Wanting to rule out the timing light (brand new), I put the inline spark plug tester back in on cylinder one. It has these very weak pulses then a brighter flash… then weak pulses on repeat. So if I’m only looking at the bright flashes, I’m not getting much spark.
I’ve swapped coil, camshaft position sensor, cap and rotor look great. Spark plug wires are… maybe 6 months old, so I’d hesitate to think that’s the issue.
Does this point back to distributor or a computer issue?
Coil is really easy to swap. Got your original?
And who's to say a timing light works like we're expecting it to work with a PCM fired ignition...but then again a coil is a coil and a spark plug is just that...
But it's a clue!
-Mac
And who's to say a timing light works like we're expecting it to work with a PCM fired ignition...but then again a coil is a coil and a spark plug is just that...
But it's a clue!
-Mac
No change.
Here’s a video I took this morning. It shows how slow cylinder 1 is firing during start up.
20240921_183134000_iOS.MOV *You will likely have to manually change the resolution from auto to 1080P in order to clearly see the light.
Here’s a video I took this morning. It shows how slow cylinder 1 is firing during start up.
20240921_183134000_iOS.MOV *You will likely have to manually change the resolution from auto to 1080P in order to clearly see the light.
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Regardless of what the timing light does, shouldn’t it spark more often than that?
Let’s say the starter turns the engine at 300rpm’s. That would mean 5 sparks per second, correct?
Let’s say the starter turns the engine at 300rpm’s. That would mean 5 sparks per second, correct?
Side note…
The whole reason I replaced the engine a year ago was an intermittent misfire. It was due to mechanical issues (blown head gasket at cylinder six).
Even after replacing the engine, I’ve had an intermittent misfire. That was another reason for replacing both crank and camshaft position sensors.
Reading another post on wranglerforum someone had similar issues with no spark/no start and it all turned out to be a PCM.
Should I be looking at a PCM from Wranglerfix ?
The whole reason I replaced the engine a year ago was an intermittent misfire. It was due to mechanical issues (blown head gasket at cylinder six).
Even after replacing the engine, I’ve had an intermittent misfire. That was another reason for replacing both crank and camshaft position sensors.
Reading another post on wranglerforum someone had similar issues with no spark/no start and it all turned out to be a PCM.
Should I be looking at a PCM from Wranglerfix ?
With a '97, as long as it's not SKIM you can just swap in another 97/98 PCM to test it. Probably more years too.
Thanks for the tag and good morning! I am up testing PCMs at this very moment and will be happy to test another.
Looking at the test service, what’s the supercharge PCM upgrade? I don’t see an asterisk, so is this different than the 2003-2005 optimized PCM?
I want to get this shipped out tomorrow, I’m tired of diagnosing stuff and not seeing any change.
I want to get this shipped out tomorrow, I’m tired of diagnosing stuff and not seeing any change.
I see you just replaced the fuel pump, so had I it went in less than a month. Do you have fuel pressure?