ECU or wiring?
bb4
05-03-2005, 07:47 PM
i recently did a motor swap with my prelude s, sohc to h22a the motor swap was a successful job. butt i used the same SOHC harness on my h22a motor b/c it didn't come with h22 harness. well my question after installing my p13 ECU my car will bogg out while just reving at 2000-4000 rpm is it b/c of my ECU or my wiring SOHC wiring harness? n e ever had this prob?..
kaimanson
05-03-2005, 08:05 PM
I think it's the harness what's giving u troubles...
ludeguy
05-06-2005, 01:26 AM
i recently did a motor swap with my prelude s, sohc to h22a the motor swap was a successful job. butt i used the same SOHC harness on my h22a motor b/c it didn't come with h22 harness. well my question after installing my p13 ECU my car will bogg out while just reving at 2000-4000 rpm is it b/c of my ECU or my wiring SOHC wiring harness? n e ever had this prob?..
i swapped from a h23 to the h22, but i imagine a swap from the S is rather similar... it's been covered on this forum many times - and there is a good write up by aceshigh if you simply search for "h22 engine swap" - with photo's and the whole 9. In any case, i'll outline a few things - I imagine your harness should work fine for the most part - but you would have to run a couple of extra wires.
when you swap to the p13 ecu - did you run the extra wires for the vtec pressure switch, and the vtec solenoid? the pressure switch should be wired to D6 on the p13 ecu, in addition the black wire that comes out of the pressure switch should be grounded to the engine block (i believe some people also route this thru to A26 - but the same result is achieved and it's one less wire to run thru the firewall if you simply ground it to your block) the vtec solenoid has to be wired to A4. It is possibly that if the ecu isn't seeing inputs from the pressure switch it is running in somewhat of a limp mode - but it is surprising that you are bogging so early in the powerband. I would ensure that the injectors you are running are the correct ones for the h22a, back when i had my swap done - the idiot shop that I unfortunatley had to use - used my old h23a injectors on my jdm h22a!!! - while basically pocketing my new h22a injectors - with the p14 my car still ran fine - but as soon as I chucked in the p13 it would bogg out like crazy, I finally figured out what those idiots had messed up and called them on their shit until they fessed up. also make sure that the cap and rotor are in good shape - and also that the engine is timed correctly - a poorly timed engine can have a terrible amount of bog in the 2 - 3g rpm range - i know because i was troubleshooting some hesitiation/bogg in that region on my 92 lude.
If you are not throwing any CEL's - I would assume your harness is doing it's job, if you are throwing CEL's - your solution is simple - pull the code and start there, tackle each CEL code at a time until you have none. I'm pretty sure there is a CEL code for the vtec pressure switch, and since you didn't mention that you threw a CEL for that perhaps you have it wired correctly....it's rumored that a faulty knock sensor (possible with a shipped engine?) can cause bogg/hesitation without throwing a code also.
anyways... best of luck. and perhaps someone who has swapped from a S rather than the SI can help you further.
i swapped from a h23 to the h22, but i imagine a swap from the S is rather similar... it's been covered on this forum many times - and there is a good write up by aceshigh if you simply search for "h22 engine swap" - with photo's and the whole 9. In any case, i'll outline a few things - I imagine your harness should work fine for the most part - but you would have to run a couple of extra wires.
when you swap to the p13 ecu - did you run the extra wires for the vtec pressure switch, and the vtec solenoid? the pressure switch should be wired to D6 on the p13 ecu, in addition the black wire that comes out of the pressure switch should be grounded to the engine block (i believe some people also route this thru to A26 - but the same result is achieved and it's one less wire to run thru the firewall if you simply ground it to your block) the vtec solenoid has to be wired to A4. It is possibly that if the ecu isn't seeing inputs from the pressure switch it is running in somewhat of a limp mode - but it is surprising that you are bogging so early in the powerband. I would ensure that the injectors you are running are the correct ones for the h22a, back when i had my swap done - the idiot shop that I unfortunatley had to use - used my old h23a injectors on my jdm h22a!!! - while basically pocketing my new h22a injectors - with the p14 my car still ran fine - but as soon as I chucked in the p13 it would bogg out like crazy, I finally figured out what those idiots had messed up and called them on their shit until they fessed up. also make sure that the cap and rotor are in good shape - and also that the engine is timed correctly - a poorly timed engine can have a terrible amount of bog in the 2 - 3g rpm range - i know because i was troubleshooting some hesitiation/bogg in that region on my 92 lude.
If you are not throwing any CEL's - I would assume your harness is doing it's job, if you are throwing CEL's - your solution is simple - pull the code and start there, tackle each CEL code at a time until you have none. I'm pretty sure there is a CEL code for the vtec pressure switch, and since you didn't mention that you threw a CEL for that perhaps you have it wired correctly....it's rumored that a faulty knock sensor (possible with a shipped engine?) can cause bogg/hesitation without throwing a code also.
anyways... best of luck. and perhaps someone who has swapped from a S rather than the SI can help you further.
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