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Hey guys Vaught this car with the swap already done h23a bluetop guy told me it has a p12 odb1 ecu. Haven't seen this before and noone seems to have done it in forums... To me car seems kinda slow till 5k where vtec kicks in. And revs passed 8k which is obviously pointless as I can feel power drop off at 7200ish. Point being is this ecu wrong for my build could I benifit from a different ecu say p06 or something I prefer to stay odb1 honestly.. anyways thanks for any input
P12 is a non VTEC ECU that is used in the SOHC F22A1 Prelude. If your H23A is a true blue top then it would be VTEC. your VTEC H23 would run much better with a VTEC ECU, possibly an OBD1 P13 or a chipped and tuned OBD1 VTEC ECU. If VTEC is kicking in, it's not a P12 ECU
Best bet would be to confirm what ECU is installed.
If it is a P12 - replace it with a VTEC ECU.
If it is a VTEC ECU you could then try and retrieve any stored codes from the ECU.
Cel lights up when I'm on the highway and shuts off when I come to a stop... Speedo is slightly off so I was assuming it was a vss issue I can't really retrieve the codes as all my equipment is odb2 I've never had a odb1 car before
Yes it will be marked on the ECU.
there should be a bar code and part number sticker on the outside. part number will always start with 37820 the next three numbers are the ECU/Chassis number, P13, P12, P06, P28 etc etc... the last three digits have to do with the transmission and ECU version.
example 37820-P75-A01
Also there is one that can be found once you remove the cover, it is on the grey 3 plug connector.
The OBD1 P13 (H22A1) doesn't have any tuning capabilities that I know of. Now what you need to find out is what injectors you are running. Stock H23A VTEC are OBD2 295cc or the OBD1 345cc H22A1 . If they are the stock H23A injectors the P13 is not mapped correctly for those injectors. You would probably benefit from trying to find a set of H22A1 OBD1 injectors.
Alright so I'm assuming pulling injectors from a 1991 to 1996 prelude is what I need I'll give them a check. dude I bought it from said it was a chipped p12 ecu so I'm guessing he just messed up on the number but it's actually chipped. should I still go ahead and swap the injectors if they are stock h23? Anyway to tell off the ecu is chipped for real?
You will have to take the cover off the ECU and check to se if there is an EPROM installed.
I have read a few threads where people had ROM chips installed in P12/P13 ECU's. There is no real time tuning capabilities for these ECU's but they do seem to have the ability to accept tuned ROM chips.
It's a p2a8 tranny I'm good with swapping in a trans but taking one apart to change the gears is unknown territory to me and prefer not to unless it's a simple unbolt and revolt type deal?
So there's the inside of the p13 not sure how to tell if it's chipped or not any pointers? Anyone know what this wire is yellow with Green stripe it's been slpliced into and the splice isn't connected to anything
That is a stock JDM P13 OBD1 ECU. If it were tuned/chipped the 28 pin OKI chip that has E6 on it would have been replaced with an aftermarket chip.
That ECU is meant to run an OBD1 92-95 H22A with 345cc low impedance injectors. It uses a resistor box for the injectors. Not knowing anything about your swap, or what has or has not been done. That's about as much as I can tell you.
As far as that spliced wire goes. I am guessing that is a picture of your OBD2 ECU connector....
Is that wire Yellow and Green or Yellow and blue?
I'm going to guess that is the smaller grey "D" connector and that wire is at Pin 10.
YEL/BLU = VCC2 - sensor voltage.
Ok guys quick question I’ve been hearing is the 37820-P13-A12 ecu is great for swaps because it’s doesnt have the immobilizer plus it’s doesnt throw any cell codes since it’s obd2? But are hard to come by... Question is does this ecu have a crank angle sensor option? I’ve been told if it has no crank angle sensor I have to run obd1 🤔
The P13 ECU makes use of three cam/crank sensors, top dead center, cylinder position and crank position. What is a crank angle sensor....... is that a civic term for CKP/crank position sensor?
I am getting ready to put in a H23A (blue top) in my 94 Accord Ex auto. What ECU should I run. Was told a P28 won't work well if at all. A chipped P75 with VTEC functionality is what I need but I can't seem to find that anywhere.
The guy that will be helping me and knows a helI of a lot more (than myself) said P28 but he based that on his H22 which he runs. I know the 2 engines are close but clearly different. He said he's going to look into it. But if I could help get an answer the better.
If you want my p06 converted to vtec chiped and tuned for the h23 bt im selling mine getting rid of the car... 150 for the ecu with the odb2 to odb1 harness lemme know
Yeah, I'll probably be wanting that if that is the only way to go. See I tried researching and aside from you, only one other person said that is the way it will work on a H23A. I've read countless people using a P13 or even a P28 which is why I am totally confused.
I'll be hitting you up in a couple days. I have to order the Engine still.
03-10-2018, 10:32 PM
H23a bluetop running p12 ecu
