NO Spark...... TBI 88 GMC 5.7 350

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mhelms83

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no pin in the "D" port :( yeah im getting fuel, but still no spark.
 

Jims86

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no pin in the "D" port :( yeah im getting fuel, but still no spark.

Your ECM is good then, and your ignition module is providing a reference pulse. can you take a pic of the top of your distributor for me?
 

mhelms83

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here it is.
 

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Jims86

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Ok, how about the top of the cap, and inside if possible?
 

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It may be a crap shoot, but since you're running out of options here....

Have you by chance cranked the motor with the dizzy cap off to make sure you don't have a broken dizzy shaft, or dizy gear or gear pin??? I'd do that. If the dizzy isn't getting dizzy, you get no spark to the plugs.
 

Jims86

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It may be a crap shoot, but since you're running out of options here....

Have you by chance cranked the motor with the dizzy cap off to make sure you don't have a broken dizzy shaft, or dizy gear or gear pin??? I'd do that. If the dizzy isn't getting dizzy, you get no spark to the plugs.

the injectors wouldnt fire....Im wondering if he has a plug wire on the coil terminal of his cap, and vise versa.
Post some pics of the engine with the air cleaner off too...the more eyes peering in there, the better. Are you comfortable with taking the ECM out and doing some electrical tests with a meter? There is one wire that I am suspiciouse of, considering the ignition is the only problem.
 
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mhelms83

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Yes the distributor is spinning. the dist. cap is new here's an inside view. Yeah im fine with pulling the ECM and doing some tests. pic #2: 1st off, i know my plug wires are a mess right now! The relay, just above the trans dipstick, i heard a "pop" noise come from that. There's no other wires to the dist. cap besides the coil and plug wires. Pic #3. I think this is the oil pressure sensor? I unplugged it and its filled with oil. Is this normal?

I don't know if i mentioned this before, when the truck broke down i was going about 35mph and it backfired 1x and sputtered a little, then nothing.... dont know if that will help
 

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Jims86

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Holy ****!!!!!!!!!!!!!!
that firing order looks way off to me. Are you sure your distributor is in correctly? we have to be sure its correct before you can take it to a shop...it is GMSB regulations!
What do ya say we take it out, and start over!? and then re run those wires?
Did you remove the distributor from the engine when you replaced everything?...We are going to stick with you on this, bud!
 
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mhelms83

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if you need more pics please let me know. and @Jims86 and @hotrodPC, you guys rock! i cant tell you how much i appreciate all the help. times are tough and i really dont have the money to put her in the shop and so far you've helped me keep her out so far. She will roar again...i promise you that.
 

mhelms83

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Holy ****!!!!!!!!!!!!!!
that firing order looks way off to me. Are you sure your distributor is in correctly? we have to be sure its correct before you can take it to a shop...it is GMSB regulations!
What do ya say we take it out, and start over!? and then re run those wires?
Did you remove the distributor from the engine when you replaced everything?...We are going to stick with you on this, bud!
ok, i did remove the dist to replace the pick-up coil because it was bad. ill pull it out and make sure to put it back right in the morning. so what about that "oil pressure sensor?" and the relay on the firewall next to the trans dipstick? would either of those cause my problem?
 

Jims86

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Did you remove the distributor at all when you replaced the parts, if not, we can skip that part....maybe.
 

Jims86

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woops! we need a traffic light in here! LoL
 

Jims86

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ok, i did remove the dist to replace the pick-up coil because it was bad. ill pull it out and make sure to put it back right in the morning. so what about that "oil pressure sensor?" and the relay on the firewall next to the trans dipstick? would either of those cause my problem?

Nope. Are you familiar with finding top dead center? I dont know what your mechanical experience is, and i dont mean to make you feel like an idiot in any way, but you are willing to make the effort, which is enough to get this figured out...even cross country.
 
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mhelms83

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Nope. Are you familiar with finding top dead center?
yeah I think so, using the mark on the flywheel? like you're adjusting the timing?
 

Jims86

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yeah I think so, using the mark on the flywheel? like you're adjusting the timing?

Ok,right, BUT...(unplug the coil, and take the plugs off of both injectors)you need to take spark plug #1 out, put your finger in the hole, and have somebody bump the starter, untill your finger gets blown out.
then line up the timing mark to 0degrees on the timing scale by hand...it shouldnt be too far from it at this point.
You are now at top dead center.
If you go by the mark only, there is a 50% chance that the cylinder is on its exhaust stroke...dont want that. The crank turns twice for each cylinder to do its job.(1/2 a rev equals 1 stroke)

You must be registered for see images attach



when you re set the distributor, the rotor should be pointing at #1, at around the 5 O'clock position.
 
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