No fire to the plugs

[need boost]

Guys please help if you can!!! I got my new motor back in and all primed up and ready to go. Cranks over good , good fuel pressure, got gas but no fire to the plugs!! Was running when I pulled it out. I had a new crank sensor so we put it on and adjusted it, pulled the ground wires off the back and cleaned them again good, swapped a good coil pack and module from a friends car and still no spark. Open to ANY ideas I really was looking forward to getting this thing running again after spending almost 6 grand in the motor build but now its just pissing me off Thanks guys Daniel Ray

 

[need boost]

Went back up to the shop after a cool down lol. The injectors are fireing, you can hear them click as you spin it over but no fire to the plugs. Help please Daniel Ray

 

[TurboDave]

All wires hooked back up??? Especially the fusable links on the starter, grounds, orange power wire off of battery for ECU.
Fuses all good?

 

[need boost]

yes to all of them. Everything works, lights on dash, fuel pump, injectors click when you are spinning it over and I can smell gas so I know they are firing, just no spark to the plugs themselves. If I had a bad fusable link on the starter something wouldn't be on would it? The motor has been out of the car for about 7 months and I am going to go up to the shop today and pull the wiring off plug by plug and check to see if maybe one of them are dirty and not making a good connecion. I checked yesterday and I had 12 v getting to the crank sensor and I had 2 wires at the coil module with 12v so it seems like I am getting power to everything. Its not the coils or module themselves as we have done swapped them from a friends car with no sucess. I wish there was someone GOOD on these cars close to me in south georgia arrrrrrrrrr. I belive I would load it up and drop it off to them and just say fix it lol. Well let me get to the shop and get busy Daniel Ray

 

[need boost]

Been at the shop all day, ready to throw something The cam sensor is working, tested by plugging in cam tool and spinning over motor. I pulled the plug from the coil pack module and tested wires to cam and crank sensor for cont. all good. Swapped out a known good computer into car no diffrence at all. Checked on cam and crank sensor for good ground on harness and got it on both so they are grounding on the pin they are suppose to on both. Acts just like the coil module is bad but we have swapped it from a friends car and still the same thing. I am getting to hate this car!!!!!! Everything works, including the injectors firing but no fire to the plugs still! Any ideas PLEASE!!! If this keeps up I am going to look for a good shop to fight with it!!!! Any GOOD shops close to south georgia? Thanks guys Daniel Ray

 

[WIKEDV6]

How did you set the cam sensor ??

 

[ITSAV6]

no spark

Cam sens set by book and caspers sens tool. The dand ign module was bad,mine too. Both less than a year old too! WTF both were running when we pulled the engines!

 

[TurboDave]

Wanna know what kills ignition modules in GN's or T/R's??
Many of us are guilty of this, myself included. We all learned over the years that one good way to check for spark was to either hold the plug wire a little way away from the plug and look for it to jump to the plug, or just have the plug out and touching ground and watch for the spark.

Now, understand, I don't know why or how, but for some reason, especially the first one, when the wire is not connected and looking for the spark to jump that gap, it tends to ruin the modules.
As I said, I can't explain it, but it's just something that I've seen happen time and time again over the last 20 years.

For whatever reason, if the plug wires aren't connected solidly at both ends, and you're using old fashion methods of looking for spark it seems to kill them.

 

[ITSAV6]

???

That's some good info,never heard that before!

 

[need boost]

turbodave, I will remember that in the future for sure but when I first tried to fire her up all the plugs was connected. We only put the plug wire on a plug out of the block [ spare plug ] after looking for spark. Weird that both of ours were no good? Mine had only been run on the car for a short time before I pulled my motor out and itsav6's was running good on his car before we pulled his motor. Weird stuff but she is running finally Got 70lbs oil pressure cold and it was still about 55-60 after it had warmed up but I haven't taken it down the road and really ran it for a long time yet. On a roller cam there really is no break in from what I know but I still ran it up and down like I was breaking a flat tappet in for about 15 mins. I don't really think I needed to but it sure wasn't going to hurt it doing it either lol. Thanks for all the help guys Daniel Ray

 

[GN owner]

GM Troubleshooting Tips

On a GM troubleshooting film for DIS systems they use a plain vacuum hose to connnect the spark plug wires to the coil terminal. What I use is a hose (don't remember the diameter) that will fit inside the spark plug female connector and a larger hose to fit over the smaller hose to fit over the coil male terminals. After the car is started use a shorting probe (a grounded insulated probe) and watch the spark jump from the hose to the shorting probe. That way you can compare all the cylinders and see any ignition problems. I noticed that since our cars are of the waste spark type one bank will be weaker than the other since the spark is jumping from the ground electrode to the center electrode of the spark plug on one bank and from the center electrode to the ground electrode on the other bank.

As to why just pulling a plug wire is killing the ignition modules is probably due to an extremely high back EMF voltage being induced across the high voltage solid state switch in the ignition module.