Spark on 1,3,5 No spark on 2,4,6?

[gunzandgearz]

That's not exactly true. A lot of pickups are labeled "towards spark plug". There's a reason for that. The pickup coil fires the gate of a SCR in the timing light. It has to be the correct polarity to fire it. If the current is reversed it won't fire. I have a timing light that won't work on the even cylinders unless I flip the pickup over ("towards spark plug" is facing the coil pack). We don't know what type of timing light the OP is using so I wouldn't trust it. I'm not saying he is getting spark on the even cylinders but using the light to check for spark is not a good way to check. I would just pull a wire off of the coil pack, hold it close to the coil pack and check for spark.

Also this is a waste spark type ignition system which means if he cranks on it every other Revolution it is going to fire in the right direction so the timing light will still be picking it up

 

[gunzandgearz]

By the way not trying to argue with you by no means this is just how I've done it over the years and continue to do it just my two cents

 

[DeltaBravo]

Okay the stock coil pack only has 3 coils . It is a waste spark system so when 1 is firing for its power stroke 4 is also firing on its exsaust stroke . So if you have spark on 1/2 your coil pack you should have it on the other side if not your coil pack is toast .

yes, I understand this and why I am posting with a question since I don't understand what I'm seeing with a lack of spark on these other cylinders.

Anyway, the problem I am really chasing is the car will start and then die after 2 seconds. Coil pack has been changed with a known good one, new ignition module, MAF conversion to LT1 style. None of which have made any improvement. (fuel pressure is verified as good at the time it dies).

Similar problem (not the spark thing, don’t know nothing about that) but starting then would die after a couple of seconds...turned out to be my crank sensor.


Sent from my iPhone using Tapatalk

 

[mikestertwo]

Also this is a waste spark type ignition system which means if he cranks on it every other Revolution it is going to fire in the right direction so the timing light will still be picking it up

Not true either. I'm not trying to argue just educate people. The current in the secondary of the coil is always in the same direction no matter what cylinder it is on. The only way to reverse it is to reverse the plus and minus on the primary of the coil which does not happen. Some timing lights are sensitive to the current direction some are not. Depends on the design of the timing light trigger circuit. That's why using a timing light with a pickup coil is not always definitive in determining whether there is spark or not. I have actually designed a timing light to trigger off of the cam sensor so I can adjust the cam sensor with the engine running.

 

[gunzandgearz]

Not true either. I'm not trying to argue just educate people. The current in the secondary of the coil is always in the same direction no matter what cylinder it is on. The only way to reverse it is to reverse the plus and minus on the primary of the coil which does not happen. Some timing lights are sensitive to the current direction some are not. Depends on the design of the timing light trigger circuit. That's why using a timing light with a pickup coil is not always definitive in determining whether there is spark or not. I have actually designed a timing light to trigger off of the cam sensor so I can adjust the cam sensor with the engine running.

Not true either. I'm not trying to argue just educate people. The current in the secondary of the coil is always in the same direction no matter what cylinder it is on. The only way to reverse it is to reverse the plus and minus on the primary of the coil which does not happen. Some timing lights are sensitive to the current direction some are not. Depends on the design of the timing light trigger circuit. That's why using a timing light with a pickup coil is not always definitive in determining whether there is spark or not. I have actually designed a timing light to trigger off of the cam sensor so I can adjust the cam sensor with the engine running.

I know you're not I'm not either one thing about doing this for 30 years as you can always learn something new I've learned that in my 30 Years also what I'm trying to figure out though is the current going through the plug wire should still sit off the timing light correct or you saying this isn't correct the current is going to the plug wire down to the plug it regardless of what the coil is doing if I'm wrong which I'm not saying I couldn't be I would like for you to school me on this

 

[No disintegrations]

I think dank said this earlier. There are really only 3 coils and they fire companion cylinders on every stroke wasted spark system yada yada. So the weird thing is how can it loose 3 cylinder? It should loose 2 or 4 cylinders not 3. If you follow me? Maybe something could cause it but it should fart on ether or squirt some gas in there.

 

[gunzandgearz]

I know you're not I'm not either one thing about doing this for 30 years as you can always learn something new I've learned that in my 30 Years also what I'm trying to figure out though is the current going through the plug wire should still sit off the timing light correct or you saying this isn't correct the current is going to the plug wire down to the plug it regardless of what the coil is doing if I'm wrong which I'm not saying I couldn't be I would like for you to school me on this

I guess what I'm trying to say is that I can see a timing light being polarity sensitive but only the electronic part that gets the battery power, not the inductive pickup side it is just looking for the magnetic field that builds up and collapses which is traveling through the plug wire the same direction every time it fires so maybe we're talking about something completely different but again I'm all about helping people on this site also learning myself but again would like to know your thoughts if I'm missing the point somewhere

 

[gunzandgearz]

Got to give a thumbs up to mikestertwo and sa I learned something new tonight as I did some research and found out that there are some lights out there that are polarity sensitive on the inductive pickup clamp I have never seen this before and have been using timing lights for many years never run across this as I have several lights andnone of them are set up this way anyway kudos to you as even guys that have been doing this stuff for 30 plus years can still learn

 

[edfiero1]

Update. I haven't done any additional troubleshooting on the strange no spark condition, but my primary problem of the car dying after 2 seconds has been solved by replacing the ECU.

 

[captndave737]

Thats how a car acts with an anti theft chip when the anti theft isn't disabled before starting. Did you use the same chip in the new ECU?

 

[edfiero1]

Yes, switched over the chips to the new ECU. TurboTweak said no Anti-Theft.

 

[mikestertwo]

What's the problem now?