No spark to engine
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No spark to engine
I am building a project car using a 2002 S2000 engine.
The engine did not come with key. I have since purchased steering column and key but it is not tied to ECM. I have the Honda Electronics manual and have studied the immobilizer system. Based on their documentation, the only thing the immobilizer does is cuts power to fuel pump if you do not have matching key. If key matches, it simply sends ground to PGM-FI relay to activate power to fuel pump. I have simply grounded the relay and pump works fine. I do get the green key on dash saying I do not have matching key.
My question is does the immobilizer do anything else that would prevent the engine from starting?
The engine will crank but i am not getting any spark from the coils. I do have power to ground and injectors.
I did check MAP sensor, Throttle position sensor voltage and vacuum lines. The timing chain has never been touched so no changes there.
The three wires going to coils are ground, power and signal from ECM to fire the coil.
Manual says the signal coming from ECM to coils is a pulse signal. I connected trouble light to output from ECM to see if i got a signal. nothing. I don't know if pulse is supposed to be power or closes a ground loop.
My suspicion at this time is that in my initial efforts to install the wiring harness and trying to find power to the gauges, I had provided battery power to the IGP1 and IGP2 connections on ECM but found out later those supply power from ECM. This may have fried it although other functions seem to work.
Suggestions?
The engine did not come with key. I have since purchased steering column and key but it is not tied to ECM. I have the Honda Electronics manual and have studied the immobilizer system. Based on their documentation, the only thing the immobilizer does is cuts power to fuel pump if you do not have matching key. If key matches, it simply sends ground to PGM-FI relay to activate power to fuel pump. I have simply grounded the relay and pump works fine. I do get the green key on dash saying I do not have matching key.
My question is does the immobilizer do anything else that would prevent the engine from starting?
The engine will crank but i am not getting any spark from the coils. I do have power to ground and injectors.
I did check MAP sensor, Throttle position sensor voltage and vacuum lines. The timing chain has never been touched so no changes there.
The three wires going to coils are ground, power and signal from ECM to fire the coil.
Manual says the signal coming from ECM to coils is a pulse signal. I connected trouble light to output from ECM to see if i got a signal. nothing. I don't know if pulse is supposed to be power or closes a ground loop.
My suspicion at this time is that in my initial efforts to install the wiring harness and trying to find power to the gauges, I had provided battery power to the IGP1 and IGP2 connections on ECM but found out later those supply power from ECM. This may have fried it although other functions seem to work.
Suggestions?
Joined: Oct 2013
Posts: 356
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From: Coningsby, Lincolnshire
I had this issue when doing my turbo build but on aem V2 ecu.
It turned out to be the crank sensor. I had the timing cover powder coated and they coated the seat for the sensor so it didn't seat properly. I cleaned up the sensor seat and made sure it was in there firm and bolted in properly. It was only a few mm but turned out to be the problem.
Also check your G101 ground on the back of the head. Without this ground the coils get no power.
It turned out to be the crank sensor. I had the timing cover powder coated and they coated the seat for the sensor so it didn't seat properly. I cleaned up the sensor seat and made sure it was in there firm and bolted in properly. It was only a few mm but turned out to be the problem.
Also check your G101 ground on the back of the head. Without this ground the coils get no power.
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