Fuel, spark and no start
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Fuel, spark and no start Hey everyone, first post! I'm sending out an SOS
Back story:
Keeping a long story short: I swapped an LS1 into my E30 BMW, the engine is rebuilt and has never run before. First go around I go to crank it and it doesn't fire at all. Pulled the plugs on #1 and 2 and they've got good spark, and I can see fuel misting out of the exhaust ports as it cranks (manifolds aren't on). The only thing I can think of is ignition and/or injector pulse timing, but I'm really unfamiliar with these engines so any help is appreciated greatly appreciated.
Back story:
Keeping a long story short: I swapped an LS1 into my E30 BMW, the engine is rebuilt and has never run before. First go around I go to crank it and it doesn't fire at all. Pulled the plugs on #1 and 2 and they've got good spark, and I can see fuel misting out of the exhaust ports as it cranks (manifolds aren't on). The only thing I can think of is ignition and/or injector pulse timing, but I'm really unfamiliar with these engines so any help is appreciated greatly appreciated.
Thread Starter
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So the engine is pretty much stock with the exception of an LS6 intake, and the ECU is flashed with a stock tune. I thought about that too but what gets me is that it doesn't fire at all. Even if the tune was off it should at least misfire or run rough or give at least some sign of life.
Just wondering because of VATS. (vehicle anti theft system) If it’s not turned off, an ECM that’s been pulled will not allow the engine to fire. If you had it flashed however, this should have been the first thing that was done.
If he's got fuel and spark then VATS isn't the issue. The PCM will shut off the injectors and the fuel pump if vats isn't reading right.
If you've got good fuel and spark... and we'll assume it's good fuel (pressure, clean injectors, correct air/fuel ratio) then the only other thing is compression. Out of curiosity, did you time any of the spark to see if timing is correct?
Was anything changed internally to the motor when you did the swap? or is it a stock (factory parts) ls1?
I would check fuel pressure at the rail, and then do a compression test on all 8 cylinders.
Also, any codes showing up? What MAF are you using?
If you've got good fuel and spark... and we'll assume it's good fuel (pressure, clean injectors, correct air/fuel ratio) then the only other thing is compression. Out of curiosity, did you time any of the spark to see if timing is correct?
Was anything changed internally to the motor when you did the swap? or is it a stock (factory parts) ls1?
I would check fuel pressure at the rail, and then do a compression test on all 8 cylinders.
Also, any codes showing up? What MAF are you using?
Are you saying that the motor doesn't fire at all? Not a sputter, but just spins over? If so that would be strange. Even if the timing is off, the motor should pop when the spark fires on a wet cylinder regardless of the timing. Even if the compression were low, the motor would fire. Are you sure it is getting spark?
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I've had a few with spark and fuel that didn't fire over. Check compression and also check firing order very carefully. One of them that I had someone put the flywheel on 90 degrees off and it was firing 90 degrees off for each cylinder. It didn't sputter, spit or anything. Just didn't fire. (this was a volkswagen and the crank sensor read off the flywheel)
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Verdad Gallardo Thread Starter
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I got it figured out. Full disclaimer I'm an idiot. It wasn't fuel I saw misting out of the exhaust ports it must've just been water vapor from cylinder compression. The fuel pump fuse was burning up from the 9amp current draw at 60psi, it's a 7.5A fuse. Now I've gotta figure out if I can retain the stock wiring with a bigger fuse or run new wiring. From the schematics it seems like it's a 1.5mm wire at the smallest point so it should be good for 20A, but I'll ask BMW people what they've done. Thank you everyone for the responses and help!!