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Discussion Starter · #1 ·
87 C4, swapped to vortec heads over winter. Once I got it all back together when I try to crank engine, the crank is totally different sounding. The engine turns over but it’s not trying to start at all- it’s just cranking. Pretty sure I’ve got no spark either to injectors or plugs.
Starter was professionally rebuilt last year, new battery. Fuses are good, rebuilt distributor, fuel pump doesn’t prime for 2 seconds, honestly I’m unsure if I’ve got connections on distributor correctly. Fuel pump was replaced approximately 6 years ago. Thank you for your help😎🇺🇸
 

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87 C4, swapped to vortec heads over winter. Once I got it all back together when I try to crank engine, the crank is totally different sounding. The engine turns over but it’s not trying to start at all- it’s just cranking. Pretty sure I’ve got no spark either to injectors or plugs.
Starter was professionally rebuilt last year, new battery. Fuses are good, rebuilt distributor, fuel pump doesn’t prime for 2 seconds, honestly I’m unsure if I’ve got connections on distributor correctly. Fuel pump was replaced approximately 6 years ago. Thank you for your help😎🇺🇸
Check for spark at spark plugs, Check fuel pressure at rail . Sounds like distributor is off.
 

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Discussion Starter · #3 ·
No spark, fuel relay on firewall of engine bay clicks but no fuel pump priming for 2 seconds w/ key in on position. Vats was disabled years ago. Rail has fuel but is not under pressure from pump. I ordered a fuel pump relay. I even jumped a wire through a 100 amp breaker to alternator. Do u know if there is supposed to be a ground wire connected to rear of left engine head on bracket just below rear lip of left valve cover?
The fuel pump relay had all cracked insulation on wires going into it. Do u know if fuel relay grounds eprom ?
I’m guessing bad relay - led to no spark, no injectors, no fuel pump condition.
I’m on tdc- rotor points on no.1 , I’m on tdc on crank, I tried putting my thumb over no 1 spark plug n could not get compression confirmation
That’s still a mystery
I’m hoping I’m close but I’ll hollar at you in a day or so once relay gets here.
I’m thinking once I install relay, everything in the electric system n fuel will be powered n I should be closer

TY
Gary 🇺🇸😎
 

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I have the same heads and have had none of these issues. Could be a timing issue. If distributor wasn't recalibrated after the install, its definitely worth looking into. You mentioned the VATS had been disabled. Was it removed or had a bypass? If bypassed, Check the method used and is it still 100% operational? If it was a homemade job you might think about a replacement. If needed, I can get you a solid replacement.

Scott Sutherland
 

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Discussion Starter · #5 ·
Vats was disable via a bypass, it’s mounted behind breadbox. If I remember correctly- the symptoms of how the car acted were nothing like today. I doubt it’s vats, I’ve got a custom oak dash I built, but I’ll open it up n look. .I’d like to send pics of how distributor is setup. I was a flight engineer on C-141B’s in the USAF I probably know enough to be dangerous on c4s. It’s possible distributor is not installed correctly. The car doesn’t sound n act like a corvette. When I crank the engine , it is absolutely not trying to start- the motor is just turning over if that makes any sense. t’s a completely different sound, void of ignition. ’ll double check spark, but current status is no spark, no injectors, fuses r all good, fuel pump relay clicks- but no audible priming of fuel pump, fuel present but Not under pressure on rails. Installed a Hotwire from battery to alternator with a 100 amp breaker inbetween n removed factory connection to alternator. 12 volts is sitting on alternator. I’m not sure if my wires r correct on distributor. I screwed pooch n didn’t get pics, n it took six months for weather to improve to work on it. From drivers side, the two connectors - installed r faded yellow/ whitish looking wire on left that’s for tach n red on right or rear part of car. Behind that is a clip of wires.
One thing of note: during this escapade🇺🇸😎 I had to disconnect oil pressure xmitter- it could not be reassembled, n I have a different female end connector on it currently. My understanding is without a 4-5 psi signal to the brain/computer she prevents engine start. It should be perfect but I’ll know when fuel relay arrives. My bro in law owned 19 vettes . He died bout 5 years ago he’d be laughing that this car won’t fire up. Also I bought longer spark plugs n gapped Em at .035”. My original plugs are not long enough for these vortex’s. Also these vortec heads have LS-1 springs on them fyi
Hope this helps
TY
Gary 🇺🇸😎
 

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Vats was disable via a bypass, it’s mounted behind breadbox. If I remember correctly- the symptoms of how the car acted were nothing like today. I doubt it’s vats, I’ve got a custom oak dash I built, but I’ll open it up n look. .I’d like to send pics of how distributor is setup. I was a flight engineer on C-141B’s in the USAF I probably know enough to be dangerous on c4s. It’s possible distributor is not installed correctly. The car doesn’t sound n act like a corvette. When I crank the engine , it is absolutely not trying to start- the motor is just turning over if that makes any sense. t’s a completely different sound, void of ignition. ’ll double check spark, but current status is no spark, no injectors, fuses r all good, fuel pump relay clicks- but no audible priming of fuel pump, fuel present but Not under pressure on rails. Installed a Hotwire from battery to alternator with a 100 amp breaker inbetween n removed factory connection to alternator. 12 volts is sitting on alternator. I’m not sure if my wires r correct on distributor. I screwed pooch n didn’t get pics, n it took six months for weather to improve to work on it. From drivers side, the two connectors - installed r faded yellow/ whitish looking wire on left that’s for tach n red on right or rear part of car. Behind that is a clip of wires.
One thing of note: during this escapade🇺🇸😎 I had to disconnect oil pressure xmitter- it could not be reassembled, n I have a different female end connector on it currently. My understanding is without a 4-5 psi signal to the brain/computer she prevents engine start. It should be perfect but I’ll know when fuel relay arrives. My bro in law owned 19 vettes . He died bout 5 years ago he’d be laughing that this car won’t fire up. Also I bought longer spark plugs n gapped Em at .035”. My original plugs are not long enough for these vortex’s. Also these vortec heads have LS-1 springs on them fyi
Hope this helps
TY
Gary 🇺🇸😎
Great information! Here is distributor and timing info. Better to have than not have.
35372


And setting idle and TPS procedures. I doubt they are related to the issues. But its a good idea to reset them after any major overhaul. Or just to make sure a previous owner hasnt jacked with them... I will go over your info in detail and provide any insight I can muster.
 

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Discussion Starter · #7 ·
Great information! Here is distributor and timing info. Better to have than not have.
View attachment 35372

And setting idle and TPS procedures. I doubt they are related to the issues. But its a good idea to reset them after any major overhaul. Or just to make sure a previous owner hasnt jacked with them... I will go over your info in detail and provide any insight I can muster.
Thanksonce it cranks it’ll help. I have a 93 shop manual, but I need an 87. Aside from shorted thermal fuses, I believe the entire electrical apparatus is controlled via that fuel control relay n comp That’s why it’s all depowered. I’ve owned her since she had 16000 miles. There are a lot of stray wires by dist n oil press xmitter. I’d love to know if one is a ground I can’t identify. Something is keeping the comp n distributor n fuel pump n injectors depowered n that’s what the root of this quagmire is.
I believe the pigtailed wires behind distributor r factory for shop testing to isolate malfunctions.
It’s a great car to learn about vettes. I want a 67/66, n I don’t want to be experimenting on a c2
I rechecked plug wires probably 10x,
N rotor cap points at no 1
Probably a ground I haven’t found or the relay I’m guessing
Do u like ur vortecs, do u have blue ls-1 springs?

TY
Gary
Great information! Here is distributor and timing info. Better to have than not have.
View attachment 35372

And setting idle and TPS procedures. I doubt they are related to the issues. But its a good idea to reset them after any major overhaul. Or just to make sure a previous owner hasnt jacked with them... I will go over your info in detail and provide any insight I can muster.
I’m thinking it’s a ground that might attach to rear portion of heads for computer I can’t find. Or the fuel relay depowers comp n entire elec system. I’ve seen parts of 85 shop manual on videos. Most likely it’s relay. There r stray pigtail wires by dist, I believe they’re for shop testing.
Do u like ur vortecs ?do u have the blue ls-1 springs on ur heads.
I want a c2 big block, getting experience on this beast. In the Air Force we called them pigs, n the pig pens were the portion of the ramp all the hard broke c-5s lived on jack stands. What works is I put her on Craigslist for sale once. She ran perfect for 5 years.
TY
Gary
 
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