Help!! New engine cranks but doesn't fire
11-12-2010, 10:50 AM
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Help!! New engine cranks but doesn't fire I've just installed a new crate LS1 from Crate Engine Depot into my LS1 miata conversion to replace an engine in which I spun a bearing 2 weeks ago. It's the 99-00 vintage. Everything was running fine (well, except the bearing!) on the old engine when I removed it.
The engine cranks but doesn't seem to want to start at all. We pulled a plug and confirmed we're getting no spark. We have plenty of fuel pressure at the rail, but the plugs are completely dry, so it seems the injectors aren't firing.
We're getting a couple strange behaviors:
1) The tach is jumping all over the place when we're cranking the engine, and then ends up sitting at some random RPM after we stop cranking, then it usually drops back to zero.
2) The check engine light is staying on all the time, but SOMETIMES after cranking, we're getting no DTC codes at all.
3) We're occasionally getting a P0335 - Crank Angle sensor. We've tried two different sensors (the known good one off the old motor and the new one that came with the crate motor).
I've confirmed that the reluctor wheel is, indeed, still the 24 tooth wheel. I've inspected the crank sensor connector and wires between the sensor and PCM for damage. Nothing visually stood out, but we haven't checked for connectivity between the sensor plug tips and the connector at the PCM. We did disassemble the sensor connector and verified that connection is good.
Any suggestions?
Cheers,
Dean
The engine cranks but doesn't seem to want to start at all. We pulled a plug and confirmed we're getting no spark. We have plenty of fuel pressure at the rail, but the plugs are completely dry, so it seems the injectors aren't firing.
We're getting a couple strange behaviors:
1) The tach is jumping all over the place when we're cranking the engine, and then ends up sitting at some random RPM after we stop cranking, then it usually drops back to zero.
2) The check engine light is staying on all the time, but SOMETIMES after cranking, we're getting no DTC codes at all.
3) We're occasionally getting a P0335 - Crank Angle sensor. We've tried two different sensors (the known good one off the old motor and the new one that came with the crate motor).
I've confirmed that the reluctor wheel is, indeed, still the 24 tooth wheel. I've inspected the crank sensor connector and wires between the sensor and PCM for damage. Nothing visually stood out, but we haven't checked for connectivity between the sensor plug tips and the connector at the PCM. We did disassemble the sensor connector and verified that connection is good.
Any suggestions?
Cheers,
Dean
