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Discussion Starter · #1 ·
so i replaced spark plugs. wires...optispark. ignition coil. ignition control module. radiator. waterpump. i tested the fuel pump...and it buzzez when connected to prime connector. could it be the computer???? bc when the ICM was bad...the car died on me....and since then no start...could it have shorted out the computer?? bc im running out of optionss to what it could be. thanks. vik
 

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so i replaced spark plugs. wires...optispark. ignition coil. ignition control module. radiator. waterpump. i tested the fuel pump...and it buzzez when connected to prime connector. could it be the computer???? bc when the ICM was bad...the car died on me....and since then no start...could it have shorted out the computer?? bc im running out of optionss to what it could be. thanks. vik
i just did the same thing with my car a few weeks back when i swapped my top end and it didnt start either. i thought for sure i did everything perfect and triple checked myself. you know what it was?....i didnt have the rotor on the opti installed correctly. take the cap back off and verify that your opti is lined up correctly. set your #1 piston at top dead center, and then put the rotor button on. it should fire up then. this is the absolute most common issue when someone has done a opti swap. if that doesnt work then start troubleshooting.
 

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Discussion Starter · #3 ·
how do i set my #1 piston at top dead center? turn the cam over?? and how will i know that that piston #1 is at top dead center?
 

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You don't need top dead center to line up the opti, on the back of the opti there is three slots, two are the same one is different, the different one, line it up with the dowel on the cam and push it on. I have never had to put the motor at TDC to put on an opti right :)
 

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Do not have same engine but would like to share 2 very recent mistakes while trying to fix my LO5 engine.

Car would crank but wouldn't start.

Replaced the ignition distributor and rotor (with an old one) - nil fix.
Towed the car back home and troubleshot ...

Found the fuel pump intermitently not operating.
When operating the pressure was 6 psi cwm3 (normal is 9 - 13 psi on my engine) - flow at injectors was not a "spray" but more a water tap appearance.

Replaced the fuel pump (not fun when tank is almost full)

Pressure checked at 12 psi - GOOD :D

But engine still would'nt start ... :mad:

Replaced the ignition distributor again and rotor. While doing that I found that I was not installing the wires properly. Did it again with correct orientation of service manual cwm5 (bad interpretation of shape of the distributor) cwm5cwm5cwm5

Car started just fine ...
 

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You don't need top dead center to line up the opti, on the back of the opti there is three slots, two are the same one is different, the different one, line it up with the dowel on the cam and push it on. I have never had to put the motor at TDC to put on an opti right :)
So true. I was explaining what i did. Im so used to doing that on older engines that its a habit of mines now.
 

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Just because the fuel pump makes noise doesn't mean is working properly. Attach a fuel pressure guage. 41-47 psi with key on, engine off.
 

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Discussion Starter · #9 ·
ok so i checked the fuel pressure....and it read 42 psi...but only when i connected the prime connecter to battery!!...bc if i wouldnt have done that .....then the reading on it was 0. bc there is fuel in the lines already.....so whats next?
 

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Well the check ball with in the pump sounds like it is failed at the very least, it should hold pressure. 42 pounds is on the low side. Remove the vacuum line on the Fuel pressure Regulator and turn pump on again, what does it go to? In theory it shouldn't matter since the car isn't running, but good time to check this>>>>>> When the vacuum line was removed what there fuel in it?

I can't express this post, posted on another forum, more, it is a great troubleshooting tool, USE IT!!!!!!!!Go step by step and you will find it.
http://www.mainstreamtopics.com/forums/index.php?showtopic=78
 
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