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

[ttypetom]

What is up with no spark on the even cylinders and spark on odd cylinders?

Start car, checked with timing light, all front wires on coil pack were not firing, anyone HELP?

Crank sensor?
Module?
Coil Pack?

What needs replacing?

Tom

 

[Bescurred]

which coil pack you got? if you have old school one i'd say coil or module is bad.

 

[Ormand]

Mmm, don't see how that is possible. The coils are wired in series, an odd cylinder paired with an even cylinder. Number 1 with number 4, 2 with 5, etc. So if the even cylinders are firing, the odd ones have to fire, too. One set fires "backward", from side electrode to center, don't know it that would affect how your timing light works or not. Usually, the coils go bad one at a time, and that will affect pairs of cylinders, even and odd.

 

[QuickWrench]

What is up with no spark on the even cylinders and spark on odd cylinders?

Are the wires hooked up?

 

[sackracing]

i had the same problem, bad ignition module.

 

[edfiero1]

Yes, I see this thread is 100 years old, but I have the same problem. I have swapped out the coil pack, and put in a new ignition module, but I have the same problem with no improvement. Like Ormand said above, I don't even know how this is possible since a single coil should fire to both banks simultaneously.

Anyone have any other suggestions??

 

[Nick Micale]

My next move would be to try a new or different ECM?

 

[mikestertwo]

Yes, I see this thread is 100 years old, but I have the same problem. I have swapped out the coil pack, and put in a new ignition module, but I have the same problem with no improvement. Like Ormand said above, I don't even know how this is possible since a single coil should fire to both banks simultaneously.
Anyone have any other suggestions??

How are you determining there is no spark? Are you missing spark on the odd cylinders or even cylinders? Have you actually pulled a wire off of a non-firing cylinder at the coil pack with the engine running to verify there is no spark?

 

[edfiero1]

How are you determining there is no spark? Are you missing spark on the odd cylinders or even cylinders? Have you actually pulled a wire off of a non-firing cylinder at the coil pack with the engine running to verify there is no spark?

Using a timing light. Timing light flashes only on drivers side cylinders.

 

[mikestertwo]

Using a timing light. Timing light flashes only on drivers side cylinders.

That's not a good way to check for spark. A lot of timing lights are sensitive to polarity. Is the engine running normal?

 

[michael evans]

Mmm, don't see how that is possible. The coils are wired in series, an odd cylinder paired with an even cylinder. Number 1 with number 4, 2 with 5, etc. So if the even cylinders are firing, the odd ones have to fire, too. One set fires "backward", from side electrode to center, don't know it that would affect how your timing light works or not. Usually, the coils go bad one at a time, and that will affect pairs of cylinders, even and odd.

Like "Ormand" said the coil fires "backward" so the polarity is reversed so the timing light does not recognize the voltage going through the wire.

 

[michael evans]

Engine will not start ?

 

[dank GN]

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 .

 

[edfiero1]

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).

 

[salvageV6]

Anti-theft in the chip?

What chip is in the car?

 

[edfiero1]

It is a TurboTweak chip, to the best of my knowledge its only there for running the larger than stock fuel injectors. Though I am not its original purchaser.

 

[salvageV6]

I would try starting it with a can of ether, if it runs more than 2 seconds you are losing fuel not spark.

I usually spray it under the rubber coupler into the throttle body after loosening the clamp.

I'd try to verify the chip with Eric as well...

 

[gunzandgearz]

All of the timing lights that I have ever seen are of the inductive pickup style, that is what the clamp that go's around the plug wire is it is just picking up the magnetic field that is built up around the plug wire when current flows through it doesn't care about polarity so your right, if it's not lighting off the timing light,you've got no spark to that side of the engine, either module or ecm

 

[mikestertwo]

All of the timing lights that I have ever seen are of the inductive pickup style, that is what the clamp that go's around the plug wire is it is just picking up the magnetic field that is built up around the plug wire when current flows through it doesn't care about polarity so your right, if it's not lighting off the timing light,you've got no spark to that side of the engine, either module or ecm

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.

 

[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.[/wow I have never seen that maybe the time and laughs I've used over the years aren't set up that way what do you have to do flip the inductive pickup around[

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.

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.

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.

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.

/QUOTE]

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.

I have never seen this but maybe it's just because of the timing lights that I have used aren't set up like this but I still don't see how checking it even if having to flip over flipping over the inductive coil is not going to tell you if it's got spark to the plug