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Mike S.
Mike S., Chevy Mechanic
Category: Chevy
Satisfied Customers: 7568
Experience:  ASE Certified Master Technician
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2003 Chevy 1500, 4.3. No spark at plugs, has spark at coil.

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2003 Chevy 1500, 4.3. No spark at plugs, has spark at coil. The distributor cap and rotor were replaced. Still no spark at plugs. The Crank sensor is good. Checked it with my scanner. The security light comes on and goes off normal. I am getting fuel in the cylinders, but no spark at plugs?????

Welcome! My name is ***** ***** I will do my best to assist you with this problem.Ask me about added features such as phone contact anytime if you wish !

you have confirmed spark out of the coil wire at the distributor when cranking it over ? or confirmed spark at the coil ?

if just the coil do you have it at the coil wire at the distributor when cranking it over ?

Customer: replied 1 month ago.
Coil secondary wire to the distributor is held approximately 1/4 inch from ground; have spark while cranking.
Customer: replied 1 month ago.
There are no codes.
Customer: replied 1 month ago.
Scanner shows 12v at the coil. While cranking voltage drops to 9.5-10 volts at coil

and there is NO spark coming out of the cap when cranking it over confirmed ?

Customer: replied 1 month ago.
No spark at the end of the secondary wire going to the spark plug!

pull the cap when cranking it over is the rotor spinning ?

if it has spark at the coil wire into the car then it is physical from the rotor spinning to send the spark out to the plug wires

it goes in the cap and hits the rotor then the rotor spinning shoots it out the plug wires

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Customer: replied 1 month ago.
The rotor is turning!
Customer: replied 1 month ago.
entered wrong number
Customer: replied 1 month ago.
I am not a novice mechanic. I have done all the tests I know to do. Compression test is good 90 psi all cylinders.
Customer: replied 1 month ago.
Yeah, I would not be contacting you if the spark was shooting out of the spark plug wires at the spark plugs!

if it has spark in but not out use a GM cap and see if that gets spark out

you understand spark in the cap it goes to the rotor and the rotor spins and shoots the spark out

if you have it in but not out and the rotor is turning the cap HAS to be the issue

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you can always get me back for FREE for any follow up any time with this question even after you rate me here at Justanswer

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Customer: replied 1 month ago.
I do understand how the spark moves through the cap and rotor. I have installed a 2 new caps and rotors. Ins BWD and a duralast gold. Checked the posts on the cap and rotor with a ohm meter.
Customer: replied 1 month ago.
Are you saying that only a genuine GM cap and rotor will work on this application?

it goes through the coil wire port which leads to the center of the rotor then when the rotors spinning it shoots the spark out each wire port to the cylinders

we have had alot of issues with these caps the best bet is a GM cap

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Customer: replied 1 month ago.
Just installed genuine GM cap and rotor, no spark at spark plug. Have spark at coil wire????

does not make sense if you have spark into the cap but not out if the rotor is turning

is it good spark ?

Customer: replied 1 month ago.
The spark will not jump over 1/4 inch gap?
Customer: replied 1 month ago.
Blue yellow spark, but as soon as it is pulled away past 1/4 inch, it stops
Customer: replied 1 month ago.
Unless all the spark plug wires failed at the same time????

Since on this cap, the tower for the coil isn't in the center top, the only thing that is could be is that you have the coil wire to the wrong cap tower.

Here is a diagram,

Customer: replied 1 month ago.
I appreciate the diagram, but the coil wire is installed in the right port!
Customer: replied 1 month ago.
When I get back home I will post a video.

Sounds great and make sure you include where that coil wire goes on the cap.

I thought you were going to post a video?

Customer: replied 1 month ago.
I will rate you as soon as I can get a video
Customer: replied 1 month ago.
Posted. I work part time on vehicles on the side. The vehicle is not running. Phantom hunting takes time. And I know you don't believe me when I say there is spark coming out of the coil wire into the cap, but no spark out of the cap. This is what is happening. I am not a novice. I was inquiring for help. Help is defined as getting the vehicle running. And why it is not running. You want a rating? Well you winger one when the vehicle actually runs and you help me figure it out. My customer won't pay me for a vehicle repair tat did not fix it. So, with my work schedule, I will not be able to post a video until Saturday.
Customer: replied 1 month ago.
Trust me the coil wire is installed right!!!!

ok

Mike S., Chevy Mechanic
Category: Chevy
Satisfied Customers: 7568
Experience: ASE Certified Master Technician
Mike S. and 6 other Chevy Specialists are ready to help you
Customer: replied 16 days ago.
Ok, Gary was the closest to figuring out my problem. Upon further inspection, I found that the coil only had one bolt in it. The other mounting bolt was a kotter key??? The coil was not grounded good enough to produce a spark that could jump over a 1/4 inch. Once I securely mounted the coil, the engine fired right up. So Gary was almost there! I almost gave up on this project. I only have 20 hours in labor figuring this one out!!!! So, just because you have spark out of the coil, it does not mean your vehicle will run.
Customer: replied 16 days ago.
Gary should be compensated for at least being close to helping me.