No spark from coil....
- Thread starter 92TyLA
- Start date
BoostedSUV
Active member
Re: No spark from coil....
ECM fuses.
ECM fuses.
BoostedSUV
Active member
Re: No spark from coil....
Coils rarely fail but can happen. As stated above ign module would be the next possible culprit.
How are you verifying spark?
Coils rarely fail but can happen. As stated above ign module would be the next possible culprit.
How are you verifying spark?
Re: No spark from coil....
Correct but it happend before to me so i switch to a MSD
unit and it works great till now i am thinking to replace the MSD
6 AL to MSD digital 6 unit !!
Correct but it happend before to me so i switch to a MSD
unit and it works great till now i am thinking to replace the MSD
6 AL to MSD digital 6 unit !!
IpHoOnDyou
New member
Re: No spark from coil....
Ign moduale, let it sit for a little bit an see if it will start back up. When you do replace the bad ign mod be sure to clean the vents at the bottom of the dizzy! These get clogged more often than not an can comenly cause it to over heat an fail
Hope that helps
Steve
Ign moduale, let it sit for a little bit an see if it will start back up. When you do replace the bad ign mod be sure to clean the vents at the bottom of the dizzy! These get clogged more often than not an can comenly cause it to over heat an fail
Hope that helps
Steve
SY2932
Administrator
Re: No spark from coil....
This is how you check to see if a coil is bad or not:
"This is a brand new MSD coil #8226. The coil does NOT have to be removed from the vehicle to perform these checks. Any connections on the terminals will have to be done with a paperclip or other small object as the test leads won't be able to reach the pins inside. This value should be infinite resistance (open). If not, replace the coil."
"From here on out, the resistive values are not "carved in stone" and are approximate. Here, the value should be very low or zero. If not, replace the coil."
"Here, the resistance should be high but, not infinity (open). If not, replace the coil. *These checks will work on a stock coil as well*."
As mentioned above, the ignition module can be at the root of the problem as well:
"If the chip is installed correctly, and you definitely have both spark and fuel pressure, your ignition module is dead. A bad ignition module won't generate a reference pulse preventing the injectors from firing. Part number is 1048-2827 (located under your distributor cap, BTW). Some auto chain stores can test to confirm it it's good or bad."
If you have it checked by a store, be sure to have them test it *several* times. Sometimes it will pass the first test only to fail subsequent tests as it heats up... HTH's
This is how you check to see if a coil is bad or not:
"This is a brand new MSD coil #8226. The coil does NOT have to be removed from the vehicle to perform these checks. Any connections on the terminals will have to be done with a paperclip or other small object as the test leads won't be able to reach the pins inside. This value should be infinite resistance (open). If not, replace the coil."
"From here on out, the resistive values are not "carved in stone" and are approximate. Here, the value should be very low or zero. If not, replace the coil."
"Here, the resistance should be high but, not infinity (open). If not, replace the coil. *These checks will work on a stock coil as well*."
As mentioned above, the ignition module can be at the root of the problem as well:
"If the chip is installed correctly, and you definitely have both spark and fuel pressure, your ignition module is dead. A bad ignition module won't generate a reference pulse preventing the injectors from firing. Part number is 1048-2827 (located under your distributor cap, BTW). Some auto chain stores can test to confirm it it's good or bad."
If you have it checked by a store, be sure to have them test it *several* times. Sometimes it will pass the first test only to fail subsequent tests as it heats up... HTH's
alwayscode390
pppssssshhhhhtttttttttttt
Re: No spark from coil....
If its the module, wont the stock tach stop fluttering when you are cranking the engine over? ---
If its the module, wont the stock tach stop fluttering when you are cranking the engine over? ---
The Bronze
New member
Re: No spark from coil....
Yes, the same wire that provides the ground to the coil, also signals the tach.
If I didn't have spark, I would split the system first.
1) Put a test light on the white wire at the coil, connect the other leg to a ground. Crank the engine and look for the light to flash. If the light doesn't come on, put the light on the pink wire. If there is power there, then the coil is open-replace. If there isn't power on that side, check to see if the turn signals work. It shares a fuse. If turn signals are inop, chase the fuse/switch. The ignition module shares power through the coil, so no power to the coil, no power to the module either. Note that the coil is not fuse protected, circuit protection comes from the fusible links.
2) If the test light lit up, but did not flash when cranking, then the module isn't providing a ground. Since the module controls the ignition until bypass speed is reached (~400rpm), it isn't a ECM issue. Most likely a bad ignition module, although you can have a stator fail as well (under the module). You can test the stator, but it is just easier for you to switch the module. If you take the module out and have it tested, you stand a good chance that it is a hot-failer, so don't assume the module is defective based off that test. I only trust testing it on the vehicle. A decent check to see that it isn't the module is to see if the injectors are firing. If they are, they are getting a signal from stator (through the module). Coil driver is usually the failure, not the EST circuitry- it typically continues to work.
Yes, the same wire that provides the ground to the coil, also signals the tach.
If I didn't have spark, I would split the system first.
1) Put a test light on the white wire at the coil, connect the other leg to a ground. Crank the engine and look for the light to flash. If the light doesn't come on, put the light on the pink wire. If there is power there, then the coil is open-replace. If there isn't power on that side, check to see if the turn signals work. It shares a fuse. If turn signals are inop, chase the fuse/switch. The ignition module shares power through the coil, so no power to the coil, no power to the module either. Note that the coil is not fuse protected, circuit protection comes from the fusible links.
2) If the test light lit up, but did not flash when cranking, then the module isn't providing a ground. Since the module controls the ignition until bypass speed is reached (~400rpm), it isn't a ECM issue. Most likely a bad ignition module, although you can have a stator fail as well (under the module). You can test the stator, but it is just easier for you to switch the module. If you take the module out and have it tested, you stand a good chance that it is a hot-failer, so don't assume the module is defective based off that test. I only trust testing it on the vehicle. A decent check to see that it isn't the module is to see if the injectors are firing. If they are, they are getting a signal from stator (through the module). Coil driver is usually the failure, not the EST circuitry- it typically continues to work.
92TyLA
New member
Re: No spark from coil....
White wire at the coil does not have a positive pulse when cranking, red one does have constant power, I'm about to replace the ignition module since It looks like it has never been replaced, truck did this to me last week and I replaced the stock coil with an msd one and it still wouldn't turn on, all i did was move the cap and rotor plugs a little and it fired right up. I still have the msd on right now
White wire at the coil does not have a positive pulse when cranking, red one does have constant power, I'm about to replace the ignition module since It looks like it has never been replaced, truck did this to me last week and I replaced the stock coil with an msd one and it still wouldn't turn on, all i did was move the cap and rotor plugs a little and it fired right up. I still have the msd on right now
92TyLA
New member
Re: No spark from coil....
long screw driver touching coil to cap also tried with a separate wire and no spark at all
long screw driver touching coil to cap also tried with a separate wire and no spark at all
92TyLA
New member
Re: No spark from coil....
Great info!!
Thanks Mike
This is how you check to see if a coil is bad or not:
"This is a brand new MSD coil #8226. The coil does NOT have to be removed from the vehicle to perform these checks. Any connections on the terminals will have to be done with a paperclip or other small object as the test leads won't be able to reach the pins inside. This value should be infinite resistance (open). If not, replace the coil."
"From here on out, the resistive values are not "carved in stone" and are approximate. Here, the value should be very low or zero. If not, replace the coil."
"Here, the resistance should be high but, not infinity (open). If not, replace the coil. *These checks will work on a stock coil as well*."
As mentioned above, the ignition module can be at the root of the problem as well:
"If the chip is installed correctly, and you definitely have both spark and fuel pressure, your ignition module is dead. A bad ignition module won't generate a reference pulse preventing the injectors from firing. Part number is 1048-2827 (located under your distributor cap, BTW). Some auto chain stores can test to confirm it it's good or bad."
If you have it checked by a store, be sure to have them test it *several* times. Sometimes it will pass the first test only to fail subsequent tests as it heats up... HTH's
Great info!!
Thanks Mike
Re: No spark from coil....
Modules are service parts just keep a spare in the glovebox !!!
Modules are service parts just keep a spare in the glovebox !!!
tnsyty
Active member
Re: No spark from coil....
Search feature proves useful :tup:
Dealing with no spark myself. No tach flutter on cranking. Truck sits for many months at a time and it didn't start the other day when I tried to move it. I am on the original distributor, so I might as well change out the whole thing instead of just the module (assuming that is what it turns out to be).
I am thinking that in the past, people liked the "ebay" version msd billet distributor? Or am I mistaken?
Search feature proves useful :tup:
Dealing with no spark myself. No tach flutter on cranking. Truck sits for many months at a time and it didn't start the other day when I tried to move it. I am on the original distributor, so I might as well change out the whole thing instead of just the module (assuming that is what it turns out to be).
I am thinking that in the past, people liked the "ebay" version msd billet distributor? Or am I mistaken?