No spark at COP connections

[Timmbo]

For those familiar my car is cranking, not starting and soaking the plugs. I ruled out the throttle body for sure. Next thing was checking for spark. I pulled all the cop connectors. The red wire to all the cops has 12v via my voltmeter. One lead to the red wire, the other to ground and showed 12v. Then I placed both voltmeter leads across the COP connector, had my son crank the car and I got absolutely nothing on the meter. First off, I did the correct procedure to check for this issue of no spark correct? Secondly, other than a PCM issue, what else could it be? Is there a fuse in the electrical distribution center?

Thanks guys.

 

[skwerl]

Crank sensor?

 

[86GT351]

Crank sensor?

Probably not. Crank Sensor should shut down the fuel circuit also!

 

[Timmbo]

Crank sensor?

No. I was getting an rpm signal during cranking that I monitored on Livelink and dumping plenty of fuel lol.

 

[BruceH]

Is the reluctor wheel that triggers the crank sensor installed?

 

[8306gt]

For those familiar my car is cranking, not starting and soaking the plugs. I ruled out the throttle body for sure. Next thing was checking for spark. I pulled all the cop connectors. The red wire to all the cops has 12v via my voltmeter. One lead to the red wire, the other to ground and showed 12v. Then I placed both voltmeter leads across the COP connector, had my son crank the car and I got absolutely nothing on the meter. First off, I did the correct procedure to check for this issue of no spark correct? Secondly, other than a PCM issue, what else could it be? Is there a fuse in the electrical distribution center?

Thanks guys.

Instead of trying to use a voltmeter for this take a small light bulb, such as license plate bulb - straighten the wires out and plug it in to the connector. It is difficult to get a reading with a voltmeter as it will only show voltage when the coil driver in the ecm tells it to fire the coil. It is a very short period of time and most volt meters won't react quick enough to see voltage. The bulb will flash as you crank the car. I would think it unlikely that all 8 coil drivers would die at one time.

 

[bcb06gt]

Probably not. Crank Sensor should shut down the fuel circuit also!

I am not doubting you, but I think my buddy had a similar issue on his Marauder (4.6 4V). The sensor connector was bad. New pigtail cured the no start. I think he was getting fuel from what he said - yes, second hand info and my bad memory.

 

[GB10]

The 12v to the coils is constant. The ground is pulsed to fire the coils, so like was said a voltmeter won't work. You could pull out a cop and put the spark plug in the boot and crank the car to see if the plug is firing. You may have to ground the plug to get it to spark. Also, check your fuses labeled pcm power.

 

[Timmbo]

Is the reluctor wheel that triggers the crank sensor installed?

Yes. Remember my car was running perfect when I pulled off my M90 kit to install the Mammoth kit.

The 12v to the coils is constant. The ground is pulsed to fire the coils, so like was said a voltmeter won't work. You could pull out a cop and put the spark plug in the boot and crank the car to see if the plug is firing. You may have to ground the plug to get it to spark. Also, check your fuses labeled pcm power.

I think your right. We have an F150 here at work with COPS so I tried my method with the voltmeter this morning by just disconnecting one COP and putting the meter across the two COP terminals at the connector. During cranking it showed nothing but once the engine started the voltage registered. Then I tried my test light. During cranking it did not light up but once the engine started the test light pulsed. I will try putting the plug in the cop, grounding it and then check for spark.

 

[michael.konor]

Even easier...

Remove COP, plug COP into connector, insert spark plug, ground spark plug outer casing, and then have someone crank your car.

See spark?

 

[Timmbo]

Yep I got spark. As I discovered the voltmeter and test light method don't work during "cranking". HOWEVER, if you have an engine that cranks, starts, continues to run and you want to check for a signal pulse across the connector the voltmeter and test light work fine.

For a crank no start I bought this dandy little 10 dollar coil tester at Oreillys. Turns out I've got plenty of spark.

 

[eighty6gt]

Way too much start enrichment? Have you tried cranking @ WOT to see if it clears some fuel and fires up?

Strange. You have spark and fuel but the car doesn't run. I'm reasonably sure you have compression.

 

[Timmbo]

Way too much start enrichment? Have you tried cranking @ WOT to see if it clears some fuel and fires up?

Strange. You have spark and fuel but the car doesn't run. I'm reasonably sure you have compression.

Yeah the engine fired right up as you see in the video on the first start with the new tune but it was pig ass rich, soaked the plugs and stalled. I ran my new stroker all summer with my old M90 kit and it ran perfect. My only mods this winter was simply pulling off the M90 kit, installing a Fore Level 4 return fuel system with ID1000 injectors and the Mammoth 2.8L kit. No cams or anything internal done with the motor. So nothing mechanical is keeping the motor from running.



And of course the more I cranked trying to restart it I made things worse. I assumed the stall was a lack of air problem because of some throttle body concerns I had. Turns out my TB is perfectly fine but...I ruined the spark plugs in the process. They are permanently fouled. So I pulled them, blew out the cylinders to make sure they are dry and now I have installed new plugs. So now that we know we have good spark, air, compression and obviously fuel Lund sent me a very basic start/idle tune for logging purposes. This afternoon I will know how that goes so I'm keeping my fingers crossed. If i can get a nice long idle log from cold to warm the rest of the tuning is down hill from here.

Here is the thread if you want to follow along. I will update it later this evening or in the morning if all goes well:
http://www.s197forum.com/forum/showthread.php?t=101598&page=22

 

[eighty6gt]

Just because I'm curious, when you first tried to start the car with the ID1000's and flooded the engine you had a start up tune in there for them, right?

 

[Timmbo]

Just because I'm curious, when you first tried to start the car with the ID1000's and flooded the engine you had a start up tune in there for them, right?

Yes. And obviously it was too rich. They reduced the fuel on the next tune revision but I think by then it was too late. The plugs were just totally saturated and ruined because of my continued cranking. Assuming it was air related and not fuel I kept cranking. Not good. Had I stopped at the first stall, pulled the plugs and blew them out I would probably be ok. But continued cranking and forcing raw fuel up to those plugs under compression will ruin them. The new tune I'm loading tonight not only has reduced fuel, but it also takes the Mafia out of the OEM maf. Basically we just want to get the car to simply idle from cold to operating temperature so we can get a nice datalog as a stable platform to build the rest of the tune. With this new tune and plugs I'd like to think we won't have an issue but we'll see.

 

[eighty6gt]

Just a mistake in the start up tune, I see.

You need a Mafia with that giant intake tube and the stock slot sensor?

Good luck, I think you have it beat.

 

[RocketcarX]

Why would the plugs be ruined?

 

[Timmbo]

Why would the plugs be ruined?

"Once a spark plug is fouled, it will not provide adequate voltage to the firing tip and that cylinder will not fire properly. In many cases, the spark plug cannot be cleaned sufficiently to restore normal operation. Therefore, it is recommended that a plug be replaced once it is fouled".


http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqfouled.asp?mode=nml

 

[RocketcarX]

I would think it would take more then fuel soak to ruin a modern spark plug.

 

[Makdaddy]

"Once a spark plug is fouled, it will not provide adequate voltage to the firing tip and that cylinder will not fire properly. In many cases, the spark plug cannot be cleaned sufficiently to restore normal operation. Therefore, it is recommended that a plug be replaced once it is fouled".


http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqfouled.asp?mode=nml

Hmmm Coming from the place that sells Spark Plugs HMMMmmmm