Any body know a thing or two about Lt1 B-body's?
04-17-2011, 09:25 AM
#1
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Any body know a thing or two about Lt1 B-body's? I'm trying to help a friend out, It's a 94 Caprice w/lt1 block stamped 327, STOCK...well except for the 26's is sitting on
The problem is it started intermittently stalling and not restarting, BLAME THE OPTI! right? ...not so fast... the problems i have found are currently these
Curently,When you cycle the key on the fuel pump does not prime ... Yes i checked the fuse and relay in the engine bay PS firewall area.. However , i can supply 12v to the red fuel pump jumper wire and pump will run continuously..after running the pump the system pressure instantly goes away (bleeds off)...normal?
secondly and maybe related
Currently,Engine wont start when pump is jumped and running OR on starting fluid ....i have tested the ICM harness plug and have voltage at A & D and has ground @ C ...but has no pulse @ B
the opti is a stocker with 125,000 miles so is the fuel pump and water pump
when i changed his plugs, wires, coil and icm a day ago it ran better ,When changing the plugs i did notice corrosion packed into the optis DS wire connections.. PACKED! with that powdery white corrosion that you find on battery terminals..I dug it all out ..i also notice that the opti is streaked red & rustly looking ..like maybe it was getting dexcool leaked on it from the pump.. anyhow
I'm sure it could use an opti and a water pump ,.. but that doesnt explain why the fuel pump wont prime on its own when cycleing the key...? I'm stumped, could the no spark be related to the no fuel prime?
or do we have two problems at once?
lil help folks
The problem is it started intermittently stalling and not restarting, BLAME THE OPTI! right? ...not so fast... the problems i have found are currently these
Curently,When you cycle the key on the fuel pump does not prime ... Yes i checked the fuse and relay in the engine bay PS firewall area.. However , i can supply 12v to the red fuel pump jumper wire and pump will run continuously..after running the pump the system pressure instantly goes away (bleeds off)...normal?
secondly and maybe related
Currently,Engine wont start when pump is jumped and running OR on starting fluid ....i have tested the ICM harness plug and have voltage at A & D and has ground @ C ...but has no pulse @ B
the opti is a stocker with 125,000 miles so is the fuel pump and water pump
when i changed his plugs, wires, coil and icm a day ago it ran better ,When changing the plugs i did notice corrosion packed into the optis DS wire connections.. PACKED! with that powdery white corrosion that you find on battery terminals..I dug it all out ..i also notice that the opti is streaked red & rustly looking ..like maybe it was getting dexcool leaked on it from the pump.. anyhow
I'm sure it could use an opti and a water pump ,.. but that doesnt explain why the fuel pump wont prime on its own when cycleing the key...? I'm stumped, could the no spark be related to the no fuel prime?
or do we have two problems at once?
lil help folks
Last edited by defaultexistence; 04-17-2011 at 09:30 AM.
04-17-2011, 09:52 AM
#2
Could be the fuel pump relay not closing to send power to the pump. The oil pressure switch is used as a back up power to the fuel pump if the relay fails. The fuel pressure bleeding off instantly when the pump is turned off is also a problem could be a leaky injector or bad check valve in the pump. The corrosion on the opti connector is not good to say the least. You will never be able to clean it all out so a new jumper harness should be put on. If there is corrosion there you better open up the opti and see how much is in there.
04-17-2011, 12:12 PM
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Could be the fuel pump relay not closing to send power to the pump. The oil pressure switch is used as a back up power to the fuel pump if the relay fails. The fuel pressure bleeding off instantly when the pump is turned off is also a problem could be a leaky injector or bad check valve in the pump.
04-17-2011, 04:22 PM
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The ecu should auto prime f pump. How wever if thee isnt a ingnition pulse it shuts the fuel down. Id def start whit the opti and harness. Verify thet there is a blue/orange spark while cranking.
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04-17-2011, 07:49 PM
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SOLVED! FIXED! I knew it would be an related electrical issue..The extra Battery terminal at PS fender well and fusible links were burnt up/faulty now has spark,primes FP ,and starts despite shitty looking opti
