car just died, no spark.

[slayne]

My wife was driving our auto p5 and i just died after about 20 mins of running. Got it to a friend's house and started trouble shooting. It has fuel, all fuses are fine, coil packs and plugs were replaced in january, and wires about 2 months ago. I have tried 3 known good coil packs, other wires, plugs.

I testd for spark and it has spark but it only sparks once then nothing. Tried on all 4 plugs and it's the same. Everything I read about this issue was either the 10 amp engine fuse or they had a a pulley or cam gear from a 626 fs. Those are not my problems. All fuses were checked with a meter and are good.

I also checked the crank sensor cuz I read about someone bending or breaking a tooth on the pulley and no start. There is a gap in the teeth and I don't know if it suppose to have a gap or if it's fully toothed all around. I thought maybe the gap is for aligning the teeth properly.

Any idea on what else to check or trouble shoot. It's the only car we have between 2 people right now and paying for rides is getting expensive.

 

[MazdaSpeeder]

Maybe it's the cam sensor itself...I'm not super familiar with the symptoms of that issue, but I know that when that part goes, the car will not run.

 

[slayne]

That's what I thought, at first I was thinking it has some miles on it and the timing belt let loose and the cam is not spinning but it's fine.

Another thing I even seen about the cam sensor is that it controls the firing of the injectors, and the crank sensor does the spark firing.

I just have no clarification on to which one actually does the spark. Not looking to replace both sensors when only need just one.

 

[pcb]

I'm pretty sure that gap is supposed to be there,... it let's the ECU know exactly where the the gear is in it's rotation.

 

[pcb]

Here's more shyte to investigate,... I'll find more.

 

[pcb]

This one sounds like it could help a lot. You don't have to use a "breakout box",.. just test at the right pin on the big ECU connector.

This one could be helpful

 

[slayne]

Most of the troubleshooting on that list seems to be unrelated to my initial issue of only one spark. If i can get the spark for function properly, then I can see what other issues are there but as of now the car won't start because it is not getting proper spark. The air gap is in spec, but I still ned to spec out what the sensor is doing. But didn't know if the gap in tooth was normal or if one broke.

 

[pcb]

Reload the page,.. I'll keep editing that one post.

 

[slayne]

I reloaded it. I ran out of time today but hopefully tomorrow I can spec out what the sensors are reading. I will report back tomorrow on what I find.

 

[pcb]

I remember trying to help Igidy with a misfire issue,.. (It would only misfire when the car was hot) when he probed the inputs at the ECU there was enough interference from either the multi-meter or the scope he had to make it stumble and misfire.

Those two sensors put out VERY low power and the signal can be easily disturbed.

If you disconnect the big plug on the ECU and test at the pins going into the car (not the pins on the ECU itself) then you are testing the wires themselves (and the sensor if it is still plugged in).

It really sounds like you had a wire or sensor failure so this test will let you know for sure. The breakout box is just a big pinout box that plugs in between the ECU and connector plug that allows for easily identifying pins for testing,... it is not needed.

At $47 to $86 for each sensor, it's good to know if it's actually dead or if it's just a bad wire. (or if it's something else entirely)

Note how BECK/ARNLEY doesn't sell a Camshaft Position Sensor,... all the have is an upper and lower crank sensor,... Good work guys,... high end parts my butt. Standard Motor products seems a little confused too.

 

[slayne]

Don't want to fork out for something that's not broke. But im going to teat the sensor at it's connecter and if that checks out I was gonna test continuity between the sensor side of the harness and the ecu plug side. Has anyone ever had an ecu go bad? My foot jam has a manufacturer sticker that says the pcm( which im assuming is the ecu) was reprogrammed in 05 or 07. It's is a dealer service sticker. What's up with that.

 

[pcb]

I remember reading that our car can run with a dead position sensor (I forget which one) but it goes into some kind of limp mode and runs like crap.

Let's hope this is your problem but your car just won't run at all.

Keep us posted.

 

[pcb]

Replacing the ECU (or PCM or ECM as it's also called) seems to be the last step in the FSM and I guess it's quite possible to have it fail.

PM Igidy if you get to that point,... he bought an extra one during his frustrating two week long ordeal trying to chase down a misfire code. (it turned out to be a bad coil,... the bad coil was brand new.)

Don't forget to check your local junk yards too (or online ones),... those things ain't cheap. ($45 to $160 for a used one on EBAY,... probably close to $10,000 at the stealership HAHA).

 

[Installshield 2]

I had the exact same issue (interesting, when a girl was driving mine...too haha) around 2006...

My timing belt tensioner and/or spring had failed, and the belt slipped...the timing belt sync's everything for the ignition to work...so it could be the direct cause of you not getting spark...I think this is much more likely than a sensor failure, or a pcm failure (as that would cause no fuel, no cranking, etc., too) especially if you had no intermittent issues before it just completely failed...

I wish i could give more details, but this happened to my car far enough from my house that i just had it towed to the dealership and repaired there...The parts list was under $100 even for factory OE stuff (i think they actually reused the belt because i had replaced it just months before, but didn't replace the tensioner or spring.........)

So i'd check that out...just by pulling the valve cover; you should be able to see how off your timing is if this is the case...

also, yes there is supposed to be a gap on the crank pulley...only one though, so if you have more than one gap, its related to that...

 

[slayne]

The beck arnley upper I believe is the cam sensor. I believe if the timing belt slipped some teeth it should be getting spark because the sensor would still send a signal, but it would be at the wrong time. So I think I can rule that out unless the ecu reads that the 2 sensors are out of sync and cut spark, but I think that's unlikely.

I read a post that said cam sensor is for injecter triggering and crank is for spark trigger. I don't know if that's accurate or not. If it is correct then the cam sensor shouldn't be causing my issue, unless, again the ecu is cutting it cuz there out of sync.

 

[pcb]

The beck arnley upper I believe is the cam sensor. Yea,... you can tell by the picture. I believe if the timing belt slipped some teeth it should be getting spark because the sensor would still send a signal, but it would be at the wrong time. I agree but I don't get why you would get one spark ??? So I think I can rule that out unless the ecu reads that the 2 sensors are out of sync and cut spark, but I think that's unlikely.Nobody really knows what the hell the ECU is doing or how it handles different situations. That can make troubleshooting difficult.

I read a post that said cam sensor is for injecter triggering and crank is for spark trigger. I don't know if that's accurate or not. If it is correct then the cam sensor shouldn't be causing my issue, unless, again the ecu is cutting it cuz there out of sync. That would be good,.. because the crank sensor is cheaper (or lower sensor if you use BECK/ARNLEY terminology.). I could see the crank sensor failing first because it is more exposed to the elements. The "electrode" on mine has corroded away to a tiny point. The cam sensor is well protected by the housing.
If I were you, I'd consider checking the sensors and harness first then consider removing the valve cover to check the crank/cam positions. (I think removing the valve cover is more labor intensive) You're still not spending any money yet while you investigate. (except for all those rides you're paying for in the meantime.)

 

[pcb]

I just noticed this:

It doesn't list no signal from the CKP sensor which suggests to me that the car won't without crank data. Perhaps it gives one spark then it knows that the crank did one full revolution (perhaps with the CMP data as reference) and kills the spark ??? I'd really love to see the ECU programming information,... I think it's a closely guarded secret.

 

[pcb]

I found this too,... But I don't know if the car has to be running,... maybe just cranked over with the key,... and I guess you need a scope.

 

[pcb]

 

[pcb]

Check for these codes: