Engine 90 gt crank no start

Darius88

Member
Apr 5, 2022
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I have a 1990 that I am restoring that doesnt want to start for anything . It hasn't ran for 14 years. I've installed new fuel pump, tank and filter, injectors,distribution cap and rotor, ignition coil, wires and plugs. And starter solenoid and a starter. I was trying to start it the other day and it would crank fine but would never start. While cranking it would act like it was going to start. I have fuel and spark to each cylinder and I've made sure my firing order was correct. When cranking and with the throttle wide open it would backfire out of the intake. The vehicle timing has never been messed with.

Has anyone ran into this issue of a crank no start and sometimes back fire.?
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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Give it a quick shot of starting fluid, if it starts and runs for a few seconds it's a fuel delivery problem, if not it's an electrical problem.
have you checked fuel pressure?
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
23,742
8,777
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What do you mean by 'checking timing'?
If you mean bring the #1 cylinder to TDC on the compression stroke and checking rotor position, that's the place to start. Then firing order.
Also check to make sure balancer is at the right place, old balancers tend to slip.
 

Darius88

Member
Apr 5, 2022
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What do you mean by 'checking timing'?
If you mean bring the #1 cylinder to TDC on the compression stroke and checking rotor position, that's the place to start. Then firing order.
Also check to make sure balancer is at the right place, old balancers tend to slip.
Yes I am going to put the number 1 cylinder to TDC and check rotor position and after use a timing gun to make sure that it sparks on cylinder 1 at the right time
 
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Darius88

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Apr 5, 2022
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I went off of this but ill double check
 

Darius88

Member
Apr 5, 2022
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after checking timing , fuel pressure and compression . The timing is perfect or near it and fuel pressure is 35 psi bus compression is cylinder 1(120psi),2(80psi),3(80psi),4(80psi),5(60psi),6(60psi),7,(0psi) 8(0psi) so I am going to do a rebuild
 
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CAMTWO1070

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Dec 17, 2021
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Sounds like bent or stuck valves...................Pop the valvecovers and look at the rocker arms and see how many are loose....

I usually get lucky with PB Blaster through the sparkplug hole and a rubber hammer to hit the valvespring............

FYI: A leakdown tester is way more comprehensive at deciphering engine issues than a traditional compression tester plus you dont have to crank the engine over to do it......It just takes a small compressor with 60psi airpressure.

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Whats funny is on my 408 that took a dump badly due to a 50/50 fault between the shop that built the engine plus Holley sending me the wrong injectors that even tuning experts couldnt detect I was running low impedience injectors on a system that was supposed to run high impedience injectors only which is a huge lie as the wrongly boxed 120lb injectors in a 36lb box ran with the Terminator X system I had originally so before it even hit 2k miles the engine just started developing a diesel knock and after I found the issue Holley just offered me 10% discount on new parts which was a huge cactus seeings it costed me $8 grand to build it and swapped out the 120lb injectors for the right 36lb ones but didnt offer a reason why low impedience injectors ran on a high impedience 36lb injector setting.... ...

When I pulled it apart it still had plenty of power and didnt smoke....It just had a diesel-like bottomend knock...Did a compression test and it revealed very little....

Did a leakdown test and the results of the test made me realize my ring seal wasnt as good as my compression test revealed so I stuck a borescope into one cylinder and found scratches in the cylinder wall which turned into all 8........LOL

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Good Luck
 

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