1994 sputtering no power 5.7 Need advice
Allright I've been reading these forums for a couple months now and am totally lost. I have a 1994 ext cab Z71 4x4 with 5.7 automatic. The problem is it has a miss and sputters with no power when in gear. When you give it gas it just wants to stall and die out but you can feather the pedal and keep it running. The timing is set at 0 with the brown wire unpluged. So far these are the parts i've tried to fix this problem.
Delphi fuel pump and strainer Fuel pressure is 13#
New fuel lines
fuel filter
both injectors
brand new fuel regulator
Throttle position sensor
IAC Vavle
Egr
pvc valve
coolant temp sensor by thermostate with perfectly cleaned grounds
195 thermostate
ac delco spark plugs
autolite spark plug wires
msd ignition coil
Brand new distributer
knock sensor
Ecm
O2 sensor
Map sensor
New y pipe and cat
I bought this truck from a friend of mine who experianced the same problem so he replaced the map,cap & rotor
So after all this i still have the same problem so I pulled the motor out and found a really sloppy timing chain, New cam and lifters,bores were in excellent condition for 200,000 miles so i left them alone, cleaned up the heads, took the valves apart cleaned them and a quick polishing to the valve seats then put the heads back together with all new seals. New one piece rear main and put her back together. Took #1 plug out and put my finger in hole and brought the motor to compression stroke. Then manually turned the hb until the lined was lined up with the timing tab. Then put my dist in num 1 pos. Unhooked the brown wire and timed it to zero.
Now even after all this the truck still runs the same. Slight miss at idle and when you put it in gear and give it throttle it want to stall right out and fall flat on its face. give it more throttle and you can barely get it up to speed but definitely not drivable. from the cat back it has a 3" with fairly new muffler on it. I'm lost her guys I've replaced everything on this that I can and still have the same problem before I started working on this beast.
No ses codes as well.
I'm baffled because after timing is set to zero I plug in the brown wire and ecm advances the timing to 32 degrees. This I can't figure out.
Now all grounds have been wire brushed and cleaned as well as all bolts when reinstalled.
So after doing all this work I'm back to the same problem the truck had when he sold it to me, definitly regretting this purchase. i could of bought a good running Z71 for what I have into this.
I have not changed the prom yet!
Allright I've been reading these forums for a couple months now and am totally lost. I have a 1994 ext cab Z71 4x4 with 5.7 automatic. The problem is it has a miss and sputters with no power when in gear. When you give it gas it just wants to stall and die out but you can feather the pedal and keep it running. The timing is set at 0 with the brown wire unpluged. So far these are the parts i've tried to fix this problem.
Delphi fuel pump and strainer Fuel pressure is 13#
New fuel lines
fuel filter
both injectors
brand new fuel regulator
Throttle position sensor
IAC Vavle
Egr
pvc valve
coolant temp sensor by thermostate with perfectly cleaned grounds
195 thermostate
ac delco spark plugs
autolite spark plug wires
msd ignition coil
Brand new distributer
knock sensor
Ecm
O2 sensor
Map sensor
New y pipe and cat
I bought this truck from a friend of mine who experianced the same problem so he replaced the map,cap & rotor
So after all this i still have the same problem so I pulled the motor out and found a really sloppy timing chain, New cam and lifters,bores were in excellent condition for 200,000 miles so i left them alone, cleaned up the heads, took the valves apart cleaned them and a quick polishing to the valve seats then put the heads back together with all new seals. New one piece rear main and put her back together. Took #1 plug out and put my finger in hole and brought the motor to compression stroke. Then manually turned the hb until the lined was lined up with the timing tab. Then put my dist in num 1 pos. Unhooked the brown wire and timed it to zero.
Now even after all this the truck still runs the same. Slight miss at idle and when you put it in gear and give it throttle it want to stall right out and fall flat on its face. give it more throttle and you can barely get it up to speed but definitely not drivable. from the cat back it has a 3" with fairly new muffler on it. I'm lost her guys I've replaced everything on this that I can and still have the same problem before I started working on this beast.
No ses codes as well.
I'm baffled because after timing is set to zero I plug in the brown wire and ecm advances the timing to 32 degrees. This I can't figure out.
Now all grounds have been wire brushed and cleaned as well as all bolts when reinstalled.
So after doing all this work I'm back to the same problem the truck had when he sold it to me, definitly regretting this purchase. i could of bought a good running Z71 for what I have into this.
I have not changed the prom yet!
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