Ls1 swap won't start I'm stumped
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Ls1 swap won't start I'm stumped
So here is a little background. I did a swap into my 93 vette for an ls1. I have a psi harness all wired in. The Injectors are firing. It has spark plenty of air and no codes are being thrown. Any input will help I have done a lot of troubleshooting and I just can't seem to find a problem. I did however notice the spark is not a nice blue it's more of an orange, I don't really know if it is supposed to be that way.
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So here is a little background. I did a swap into my 93 vette for an ls1. I have a psi harness all wired in. The Injectors are firing. It has spark plenty of air and no codes are being thrown. Any input will help I have done a lot of troubleshooting and I just can't seem to find a problem. I did however notice the spark is not a nice blue it's more of an orange, I don't really know if it is supposed to be that way.
#4
What was your method of verifying the injectors are pulsing, have you tried a squirt of starting fluid in the intake? If engine has been sitting awhile the injectors can be stuck, it is a common problem on junkyard engines.
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Cover your basics. Is it getting fuel? (are the plugs wet or smell like gas) Does it have good spark (spark should be bluish not orange, indicates to me you have a weak ground or a weak positive connection or something) and does it have compression (this would be very apparent)
#7
Need to eliminate the injectors as a cause for a no start condition, my suggestion was to try a squirt of starting fluid just to see if it will pop or fart, I would hope the OP is smart enough not to empty a can of starting fluid in the intake. But then again I see your point I've seen mechanics pressure wash a radiator.
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Ok as for the injectors I have already taken them off and cleaned them myself with gum out and seafood using an old fuel pump and hose with a switch I wired to pulse the injectors and they are all shooting plenty of gas now. I have visually watched the fuel injectors while cranking fire independentlty so I don't see fuel being a problem. I have not used starting fluid but ill give it a shot I'm thinking ill use two and a half cans or so lol I'm kidding. As for grounds I will check those tomorrow that might be my issue but I show the block has ground with my voltmeter however I will ohm it out.
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I did that and that is how I came up with having an orange spark all around. I am going to add more grounds just in case. You can never have enough grounds
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Ok as for the injectors I have already taken them off and cleaned them myself with gum out and seafood using an old fuel pump and hose with a switch I wired to pulse the injectors and they are all shooting plenty of gas now. I have visually watched the fuel injectors while cranking fire independentlty so I don't see fuel being a problem. I have not used starting fluid but ill give it a shot I'm thinking ill use two and a half cans or so lol I'm kidding. As for grounds I will check those tomorrow that might be my issue but I show the block has ground with my voltmeter however I will ohm it out.
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2nd the pop and fart w some carb clean, starting, brake clean, gas.
also pull an injector connector and connect a test light. the pink should be hot at all times and the other side should flash when turning the motor over
also pull an injector connector and connect a test light. the pink should be hot at all times and the other side should flash when turning the motor over
#16
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Also wanted to add, here is what your pinouts should be. Double check your low reference and your grounds. The low reference wire is basically a ground coming off the PCM so that it can tell what the resistance is across the circuit etc etc. Basically it should also be a ground when the key is on.
Drivers side
Passengers side
Drivers side
Passengers side
#17
Keep in mind the OP is using PSI's harness...which is not exactly like factory. In fact talking with Jon at PSI, its proprietary on how the harness is wired.
OP, did you go through the trouble shooting tips on the last page of the manual?
"NO-START
1. Red Ignition Wire (From back of Fuse/Relay Center) has 12-volts with the Key in the ON position and CRANKING positions. This cannot be stressed enough, most NO-START conditions can be traced to this wiring issue.
2. Check Fuel Pressure for correct value (Approximately 58-psi).
3. Check that Fuel Injectors are firing. In many cases, engines which have been sitting for a few months have old fuel which has turned to varnish and clogged the injectors. A simple way to check if the injectors are clogged is to place a NOID LIGHT (Available at most autoparts stores) in the injector plug while cranking the engine. If the plug lights up, then the injectors are being commanded to fire. If the spark plugs are firing, the fuel pressure is correct, then the injectors are clogged and must be cleaned."
OP, did you go through the trouble shooting tips on the last page of the manual?
"NO-START
1. Red Ignition Wire (From back of Fuse/Relay Center) has 12-volts with the Key in the ON position and CRANKING positions. This cannot be stressed enough, most NO-START conditions can be traced to this wiring issue.
2. Check Fuel Pressure for correct value (Approximately 58-psi).
3. Check that Fuel Injectors are firing. In many cases, engines which have been sitting for a few months have old fuel which has turned to varnish and clogged the injectors. A simple way to check if the injectors are clogged is to place a NOID LIGHT (Available at most autoparts stores) in the injector plug while cranking the engine. If the plug lights up, then the injectors are being commanded to fire. If the spark plugs are firing, the fuel pressure is correct, then the injectors are clogged and must be cleaned."