i just brought a 1998 honda prelude sh very nice looking car and i think i got it at a good deal (1500.00) the owner before had it turbo and at some time it blew the motor, he had a used motor (h22a) from a 1997 prelude installed with 86k miles on it but no one can get it to run all it will do is spin over, i was looking and i found the that some one wrote on the ecm OBD1 and in fact it is a p13 being this thing is all stock now can i use a OBD2 on it now, i also was told i could use a ECM from a SOHC ??? true or not ??? can some one PLEASE tell me what to do to get this car going again ??? what should i do about the immobilizer being i'm changing the ECM ? thanks

 

if you are OBD2 you need a OBD2 ECU. A OBD1 ECU will not work. Using a sohc ecu will have a diff. air fuel ratio and will cause the engine to run very rough and possibly blow up. You will need a Prelude SH ECU to make this car run again. From what I remember tho's ECUs are very pricey b/c they are rare

 

where would be the best place to get one and what about the immobilizer how do i get around that because i do not have the red key but the owner before me was runing OBD! because it was turbo and they blew the motor and they put a new in and was tring to use the old ecm (OBD1) with a H22A4 which is a OBD2

 

if you don’t have emissions you can run a p72 ecu. You will just need a OBD2 to OBD1 harness. Witch if that’s what the previous owner was running you might still have it in the car.
What happen to the old ECU he was running...just use that if you still have it. If you run a p72 (GSR ecu) you can buy one from ebay or hmotorsonline.com chipped with CROME or HONDATA (tuning software) You can get it with a h22 base map Then you will need either a street or dyno tune to insure your air fuel ratio is 100% correct.

 

the guy was running a p13 using a OBD2 to OBD1 but that ecm has 2 broke items inside of it, do you think i can have it repaired and then use it but should i have it retune because they were using it with a turbo ? thanks