GVR-4
Well-known member
Ok, guys. I've been trouble shooting for a week or two and can't figure out what I got wrong with the wiring.
Background: This is a 4g61t swap into a 1990 AWD Colt Vista wagon. It's 1990 turbo ECU configuration; essentially a SOHC NA to DOHC turbo swap. There were 18 conductors out of the 52 on the ECU that were different. I was very careful with the wiring, but clearly I must have gotten something wrong or missed something. Engine will turnover, but no spark. Once I have the ignition system working properly, I can see if there are any issues with the fuel system.
Below is what I know.
* ECU is good (ran my 2.3 Mirage turbo)
* coil pack is good (ran Mirage)
* PTU is good (ran Mirage)
* there is +12v power to the coil pack when ignition is in the RUN & START positions
* tried another plug wire on #3, still no spark
* no voltage change on coil pack when key is in START (verified with analog meter)
* CAS is good from bench test
There's a lot more to unpack, but I'll start here. I'm trying to go back to the fundamental question "What has to be true for the coils to fire?", but I'm stumped. If anyone has any ideas, please let me know.
Thanks.
dp
Background: This is a 4g61t swap into a 1990 AWD Colt Vista wagon. It's 1990 turbo ECU configuration; essentially a SOHC NA to DOHC turbo swap. There were 18 conductors out of the 52 on the ECU that were different. I was very careful with the wiring, but clearly I must have gotten something wrong or missed something. Engine will turnover, but no spark. Once I have the ignition system working properly, I can see if there are any issues with the fuel system.
Below is what I know.
* ECU is good (ran my 2.3 Mirage turbo)
* coil pack is good (ran Mirage)
* PTU is good (ran Mirage)
* there is +12v power to the coil pack when ignition is in the RUN & START positions
* tried another plug wire on #3, still no spark
* no voltage change on coil pack when key is in START (verified with analog meter)
* CAS is good from bench test
There's a lot more to unpack, but I'll start here. I'm trying to go back to the fundamental question "What has to be true for the coils to fire?", but I'm stumped. If anyone has any ideas, please let me know.
Thanks.
dp
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