Cranks, fires then dies after rebuild

lol! No it can't be haunted.

no worries. I am going to call it for today. Tomorrow I will double check my 02 sensor connections and look into the 02 sensor data. I may cruise the junkyards in Indianapolis to see if any of them have a MAF for a test article.
 
Not sure if the car can run without the primary o2, but might be worth a shot. I know it can run without the secondary for sure though.
 
I checked the harness connections for the 02 sensors. Theyre connected and no obvious signs of wire damage. Hooked up torque and was looking at the 02 sensor and found something odd (I think).

Should the catalyst temp bk1 sensor 1 be 1000 degrees? No start attempts, only one key on engine off cycle and maybe 20 seconds. Doesn't that seem unusually fast to heat that quickly?

Fuel rail pressure was ~287psi. Just checking to make sure this makes sense. Without a start attempt the high pressure fuel pump hasn't been given a chance to pressurize the system.

Been reviewing the mazdaspeed teoubleshooting manual and wanted to put eyes on my ac cutout switch. It's connected, I almost wish it wasn't. Will break out the meter later just to make sure it's still good.

The work continues. Lol
 

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Haven't done a wiring check off the O2 sensors but it's on the list.

Since I was unsure the quality of the injectors manufacturer, I wanted to check resistance.
Fuel injectors resistance
Manual States 1.0 to 1.2 ohms at 65 degree F
#1 1.3 ohms
#2 1.3
#3 1.3
#4 1.2
Ambient temp is 55 degrees and engine coolant temp says 70. Car is in a garage. Does anyone have a spare laying around to benchcheck? I sent my originals out to get cleaned and checked.

Using Forscan Lite now. So if you can think of any parameters and the name, I'll log them!

Noticed there is a buzzing from the throttle body for 5 seconds after key off. Is this normal?

My next steps are to go through the starts and stops after two seconds troubleshooting tree to start and reveiw the troubleshooting post on this forum some more.

I'm going to create an excel with the various results to make sure I don't miss anything.
 
Decided to get back to basics after not finding anything with the 02 sensor and the ac pressure switch.

The compression test was 160 to 165 psi on all cylinders on the cold engine.

While doing the compression test, I decided to do a spark test. Originally, I used an inline spark tester and only watched for a few moments. This time, I used an alligator clip to ground the plug to the ground of the harness (hpfp area) and watched the spark while I cycled the engine for compression test. Before I started, I removed that ground connection and lightly abraded the terminal and mounting. The spark strength fluctuated from strong to weak to none, and sometimes none to weak to strong and had an irregular pattern. This occurred on all the cylinders, i went one cylinder at a time. I verified the harness ground by measuring resistance to the negative terminal ground. Read 0.0 ohm. I don't have the right pins to test to the pcm. Will make a few up tomorrow at work.

Decided to check resistance on the ocv. It's was 7.0 ohm. Should be 6.9 to 7.9 per the manual.

I also checked my cam position sensor while I was there and took a look at the wheel on the camshaft (what I could see). Nothing abnormal. Will check wiring on this and ckp with some test leads tomorrow to make it easier.

Checked the crankshaft position sensor. Put the pin in to locate 1 tdc on the crankshaft and a bolt in the pulley. Still aligned at the 20th tooth. The only thing I didn't do was check the airgap. Will do that tomorrow.

Last thing I did was check the coil using the igniton coil inspection on 1-18B-3 of the manual. Do I understand it correctly, A to C and B to C should be open or read some resistance? The manual states 0 ohm not normal (infinite ohm is normal).
My readings
Cylinder 1
AtoC 17.98 mohm
BtoC 17.43 mohm
AtoB 1.768 kohm
Cylinder 2
AtoC 17.76 mohm
BtoC 17.68 mohm
AtoB 1.776 kohm
Cylinder 3
AtoC 17.91 mohm
BtoC 17.90 mohm
AtoB 1.772 kohm
Cylinder 1
AtoC 16.71 mohm
BtoC 16.71 mohm
AtoB 1.871 kohm
 
Did you check the fuel pump resistor? I've heard of people bypassing it, but if it's unplugged or just bad, your car will start and almost immediately die.
 
IIRC he had good rail pressure, which can only be the case if the HPFP is fed properly.... Besides, the car WILL idle and drive on ITFP pressure (his was normal HPFP pressure in the log I believe) after a couple of start attempts, normally.
 
All coil harnesses check good to pcm, Bat + when key on, and Ground checks good.

Hopefully these videos come through. Because it's weird. Got the battery on a charger. Strong spark on 1 and 3, weak on 2 and intermittent on 4. In the first video.

Swapped 1 to 4 and 2 to 3 then retest. 2nd video.

Sorry about the glare on the windshield in the picture.

Checked the grounds at front of transmission, pass side eng mount, pass side frame rail. Getting ready to remove battery and box to check top of transmission.
 

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I don't think it's a spark issue. Seems more like some kind of sensor/logic issue than anything, otherwise it wouldn't start at all, especially if you're saying it starts and runs for a few seconds then just dies; this seems like it runs just long enough for the O2 to warm up and kick in, which is why you don't see a change in O2 readings during a cold start.

Also, there's a built in heater circuit for primary/wideband o2 sensors so that it takes less time for them to warm up and become functional, so it's not unreasonable for a sensor to be hot even if the car has not actually started yet.
 
Yeah. Just checked every ground i could find. I'm going to check the crank and cam position sensor per the manual.

Once I verify them, am I looking at a possible pcm. Just based on this thread. I know it's tough to say without being here and putting hands on yourselves.
 
Yeah it's weird. You've got what looks like good crank signal (and cam as well or it wouldn't start and would throw a code), but never does it ever show an AFR number, no matter what. I wonder if it might start with all the o2 sensors unplugged (it *should* have a MAP fallback).

You didn't purchase an aftermarket O2 and install it recently, did you? A lot of them just don't work right in these cars.
 
Enki said:
Yeah it's weird. You've got what looks like good crank signal (and cam as well or it wouldn't start and would throw a code), but never does it ever show an AFR number, no matter what. I wonder if it might start with all the o2 sensors unplugged (it *should* have a MAP fallback).

You didn't purchase an aftermarket O2 and install it recently, did you? A lot of them just don't work right in these cars.
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The o2 is the original when I picked the car up. Which ran, but only on 3 cylinders lol.

Still no codes. :(

I will give unplugging the o2 sensors a shot tomorrow and will report back.
 
No change with o2 sensors disconnected. I have attached a Forscan Lite data log and car information pulled from Forscan.

Would an issue with the condensor (as shown on the same circuit as the Bat + of ignition coils) cause these ghost issues? I see it is a capacitor but what does it do for the system? I also cannot locate it above the crankshaft pulley, but mounted on a bracket near the hpfp (I think).

If I get Forscan for my laptop with license, would I be able to reflash the pcm? Is that even possible with stock map? I bought the lite license ( do not ask me why, I chowder headed and bought the one for my mobile) .

I am at a total loss. I am grasping at straws. I will probably step away for a few days, reset and try again.
 

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While taking time to look at the data while it was attempting to run i noticed a curious thing.

VPWR 11.93v drops to 9.8v at start and stays there until the engine starts to die.
GENVDSD calls for 14.06v and ALTT V(V) is 12.38 but VPWR doesn't start to increase until after the engine starts to die.

Am I losing the engine due to the low voltage and Alternator not reaching 13 to 14 volts for charging?

I replaced the alt connector due to the tab being broken before I reinstalled the engine. I used the sumitomo called out in the connectors post on here.

I verified that the wiring, Grey and blue, are in the right orientation of the connector.
 
A dead cell in the battery can bring the entire charging system to its knees. Could be bad batt that looks good with residual charge but can't handle the load of running.
 
Easter Bunny said:
Have you tried jumping the car to start? Is the battery dying?
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I had the battery charged and tested at Autozone this past weekend. They said it was good. I kind of questioned if it really was.

I don't have jump pack or jumper cables. Something I definitely should have in case of emergency. I'll remedy that tomorrow and give it a shot.
 
I would loan you my deathbox (500 farad cap bank in toolbox formfactor) but you're kind of far away. I'm pretty sure it's empty and trying to charge it straight up would likely set your jumper cables on fire, so there's that too.
 
Enki said:
I would loan you my deathbox (500 farad cap bank in toolbox formfactor) but you're kind of far away. I'm pretty sure it's empty and trying to charge it straight up would likely set your jumper cables on fire, so there's that too.
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Lol. Thank you though!
 
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