Hello Everyone,
I'm new here.
I have a '92 Cavalier RS Convertible with the LH0 and 5 speed manual. Some friends and I have been preparing this car for 24 Hours of Lemons endurance racing. The motor will not start. Our first race is in a month. Important details below:
This car did run when we received it though it was leaking fluids from just about everywhere (two failed head gaskets, leaking PS, leaking oil pan, leaking camshaft cover, leaking valve covers, leaking cooling system). It has been completely disassembled, with the exception of the transmission internals and the bottom end, stripped of all items unnecessary for racing, and reassembled after a full cage build.
All that remains in the interior is: cage, seat, FE, battery, shifter, steering column, 3 pedals, instrument cluster, and the ECU.
Concerning the engine we eliminated: power steering (kept the pulley), heater and A/C components and simplified the cooling system (kept the A/C compressor and pulley), all emissions control items (we have catch cans for the front and rear banks and the transaxle breather), EGR system, radiator fan.
Last year the engine ran great on track and the brakes, motor mounts, and suspension bushings failed. In April of this year the engine ran for two 20 minute sessions on track perfectly. After that we couldn't get it to run properly so we started throwing parts at it including: fuel pump, battery, plugs, coils, ICM. At various times after the first no-start condition the motor would start and run indefinitely at idle, not start at all (hot or cold), start when cold but not hot, start and stall after a few seconds, start and run for 5 minutes of driving then stall. Now it won't start at all.
Part way through the build I replaced the ECM and swapped over the MEMCAL. At that time the motor would start and run for a while then stall with both the original ECM and the remanufactured one. The "original" ECM was also remanufactured so it had been replaced at least once before the car came to me.
The only codes displayed by the self diagnostic were fuel pump low voltage and MAP sensor something. We had rewired the fuel pump for direct control via switch, relay, and fuse because the original relay was melted. The fuel pump low voltage made sense because I didn't connect the relay output to the fuel pump voltage sensor pin on the ECM. I have since made sure that the fuel pump voltage input on the ECU is receiving B+ and replace the MAP sensor.
When the motor was out I replaced (among other unrelated items): IAC valve, TPS, CPS, ICM, coil packs, plugs, wires, knock sensor, coolant temp sensor, oil pressure sensor, IAT sensor, MAP sensor.
At this time the fuel pump runs and we have adequate pressure at the rail. The plugs are sparking. Neither ECM will tell the either bank of injectors to open as confirmed by NOID light. We verified continuity in the wiring from the ECU connector to each of the injector connectors.
I have the factory service manual and have been going through the diagnostic flow charts and keep coming to "replace ECM" and if still no injector pulse then "replace MEMCAL".
Also the self SES/CEL no longer lights up and will not even display code 12 so I have no idea what codes it might be throwing.
So...here are my questions: Is the MEMCAL a part that is known to fail? I can't find a replacement part anywhere online. Where can I buy one? Could I now have two non-functioning ECMs? Are there any sensor inputs to the ECM that can cause it to decide not to pulse the injectors?
My next steps are to: purchase another reman ECM, return the fuel pump control wiring to stock, test the "on" voltage of all the inputs to the ECM and compare to the factory service manual ranges.
What have I missed? What more information can I provide? What additional steps should I make?
Thank you in advance,
Jason
I'm new here.
I have a '92 Cavalier RS Convertible with the LH0 and 5 speed manual. Some friends and I have been preparing this car for 24 Hours of Lemons endurance racing. The motor will not start. Our first race is in a month. Important details below:
This car did run when we received it though it was leaking fluids from just about everywhere (two failed head gaskets, leaking PS, leaking oil pan, leaking camshaft cover, leaking valve covers, leaking cooling system). It has been completely disassembled, with the exception of the transmission internals and the bottom end, stripped of all items unnecessary for racing, and reassembled after a full cage build.
All that remains in the interior is: cage, seat, FE, battery, shifter, steering column, 3 pedals, instrument cluster, and the ECU.
Concerning the engine we eliminated: power steering (kept the pulley), heater and A/C components and simplified the cooling system (kept the A/C compressor and pulley), all emissions control items (we have catch cans for the front and rear banks and the transaxle breather), EGR system, radiator fan.
Last year the engine ran great on track and the brakes, motor mounts, and suspension bushings failed. In April of this year the engine ran for two 20 minute sessions on track perfectly. After that we couldn't get it to run properly so we started throwing parts at it including: fuel pump, battery, plugs, coils, ICM. At various times after the first no-start condition the motor would start and run indefinitely at idle, not start at all (hot or cold), start when cold but not hot, start and stall after a few seconds, start and run for 5 minutes of driving then stall. Now it won't start at all.
Part way through the build I replaced the ECM and swapped over the MEMCAL. At that time the motor would start and run for a while then stall with both the original ECM and the remanufactured one. The "original" ECM was also remanufactured so it had been replaced at least once before the car came to me.
The only codes displayed by the self diagnostic were fuel pump low voltage and MAP sensor something. We had rewired the fuel pump for direct control via switch, relay, and fuse because the original relay was melted. The fuel pump low voltage made sense because I didn't connect the relay output to the fuel pump voltage sensor pin on the ECM. I have since made sure that the fuel pump voltage input on the ECU is receiving B+ and replace the MAP sensor.
When the motor was out I replaced (among other unrelated items): IAC valve, TPS, CPS, ICM, coil packs, plugs, wires, knock sensor, coolant temp sensor, oil pressure sensor, IAT sensor, MAP sensor.
At this time the fuel pump runs and we have adequate pressure at the rail. The plugs are sparking. Neither ECM will tell the either bank of injectors to open as confirmed by NOID light. We verified continuity in the wiring from the ECU connector to each of the injector connectors.
I have the factory service manual and have been going through the diagnostic flow charts and keep coming to "replace ECM" and if still no injector pulse then "replace MEMCAL".
Also the self SES/CEL no longer lights up and will not even display code 12 so I have no idea what codes it might be throwing.
So...here are my questions: Is the MEMCAL a part that is known to fail? I can't find a replacement part anywhere online. Where can I buy one? Could I now have two non-functioning ECMs? Are there any sensor inputs to the ECM that can cause it to decide not to pulse the injectors?
My next steps are to: purchase another reman ECM, return the fuel pump control wiring to stock, test the "on" voltage of all the inputs to the ECM and compare to the factory service manual ranges.
What have I missed? What more information can I provide? What additional steps should I make?
Thank you in advance,
Jason