no spark in cylinders one and two?

Hi,

I attached a pic below showing the wiring to the coils. First, with the key on, check if there is power present at the yellow wires on cylinders 1 and 2. If there is, then confirm there is continuity to ground via the white wire with a black tracer.

Note that each of the coils has these color wires. Since you have spark on cylinders 3 and 4, I know both are present. However, there are a few different splices that may have failed for cylinders 1 and 2.

Let me know.

Joe

See pic below.

There are 4 wires on each coil they go to ECM. There is 12 volt and ground at each coil. wiring checks good to ECM connector.

Hi,

How did you confirm ground? If you have power, the ground path is what completes the circuit and fires the coil.

If you have constant ground, that is a problem. If you haven't already, try this. Take a test light and connect the alligator clip to the battery positive. Probe the IGT1 and IGT2 pins with the test light and have a helper crank the engine. The test light should strobe on and off. If that is happening and you have power, something is wrong with the coils.

Let me know what you find.

Joe

Hooked four spark plugs with coil on each one with ground on bottom of spark plug. turned the engine over and 3 and 4 had spark. checked with led test light on 4 pin connectors had red light on left pin and green light on the right pin.

Hi,

I'm not familiar with the tool. Red means what and same with green? When you checked for a ground signal, did you get a strobing light indicating a ground path is present?

Let me know.

Joe

left to right #1 12+volts with red light, #2 pulse red? +volts, #3 no power and #4 green was a ground. Test light with red and black Leeds to battery with led light.

Hi,

I'm not sure where you are looking. There is no green wire on cylinders 1 and 2. Those are the affected cylinders, correct?

If you look below, the yellow wires should have power with the key on. Take a test light and place the alligator clip on the battery neg to check.

Then, remove the test light alligator clip from neg and place it on the positive battery terminal. Probe the IGT 1 and IGT 2 terminals while a helper cranks the engine. Those wires should cause the test light to strobe.

Let me know.

Joe

See pic below.

looking at plug end that goes on coil left to right #1 12 volt +, #2 puls, #3 no voltage and #4 is ground.

Test light is led with red(+) and green(-) light with red and black leads.

Hi,

I just realized something. You are describing the connector and not the schematic. If you look at the wire colors I provided, do they indicate the correct things? If so, just to confirm, perform the test below. If that tests good, the coil pack itself is the likely problem. I say that because you should be getting a strobe from the IGT wire (pink or red). The IGF is the ignition feedback, and you should see that unless the coil is doing its job. If you look at pic 1 below, the numbers of the pins are identified in the schematic I provided. They are just in a different order.

You can also switch the coils between cylinders 1 and 3 to see if then you get a spark. Try this and let me know.

Sorry about the confusion. LOL Nothing was making sense to me. Also, remember that the IGT pins won't power anything. They are what provide a ground patch to complete the circuit and cause the coil to fire at the right time.

Let me know.

Joe

See pics below.

I have swapped all 4 coils and only get spark on 3 and 4.

Did you confirm there is power at the connector as mentioned above?

Let me know.

Joe

yes, on all four cylinders and have swapped coil packs and spark plugs.

Hi,

The ECM supplies a 5V reference voltage on the IGF circuit shared by all coils. Each time a coil fires, its igniter pulls the 5V reference voltage to ground. Check to see if that is present.

Let me know.

Joe

I get a pulse on the number 2 pin on all coil connectors to ground

Are you getting a 5v reference at the IGF pin?

Let me know.

Joe

my volt does not see it quick enough to register 5 volts. the red light flashes about half bright.

Hi,

The voltage is lower, so the brightness doesn't surprise me. Since you are getting that signal, the computer thinks it is working. The only thing I can think of is a faulty ground.

I am going to ask the site owner for his input. Let's see if he has other thoughts.

Take care,

joe

thanks.

Is the coil getting trigger from the PCM when unplugged?

yes.

If you are getting trigger and you swapped the coils out and you have a good ground, it sounds like the coil drivers inside the PCM are bad/weak. I would try a rebuilt PCM or send yours in for testing.

thanks.