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I bought a 2002 HX with a D17A2. I had a non vtec ecu and harness. I bought a vtec ecu and harness and have hooked up as much as I can except for one plug. I cannot find where it goes. I’ll attach a picture, can anyone help? Car will turn over but won’t start. It will start and run with old ecu. Wire colors attached to plug correspond to: EGR valve/position, and VTEC solenoid.
I found this picture online but do not see the connector with the green sticker on my car.
the chip in the key is programmed to the ECU.
Look in the internet, there are some key shops that do programming.
Else, need to drive to dealer using non-VTEC ECU, swap to VTEC ECU and have them program key
If you use a different car's ECU, even if another HX, you would have same issue.
the chip in the key is programmed to the ECU.
Look in the internet, there are some key shops that do programming.
Else, need to drive to dealer using non-VTEC ECU, swap to VTEC ECU and have them program key
If you use a different car's ECU, even if another HX, you would have same issue.
Excellent info here guys, if 100% an immobilizer issue, won’t be terribly hard to correct just a pain, THANKS GUYS!
If the green key in the cluster is flashing it's an immobilizer issue.
EGR isn't on every 7th gen Civic, I never understood which ones have it and which don't. Since the D17a2 harness has a connector it's safe to say the ECU will be expecting it and likely throw a fault.
Is it possible you have the wrong ECU? The ECU model changed on the integra when the facelift model came out; did the same thing happen to the civics? It’s possible that the car has an ‘04-‘05 engine and you bought an ‘01-‘03 ECU, or vice versa.
Is it possible you have the wrong ECU? The ECU model changed on the integra when the facelift model came out; did the same thing happen to the civics? It’s possible that the car has an ‘04-‘05 engine and you bought an ‘01-‘03 ECU, or vice versa.
I assume that’s possible, I’m hoping somebody with some knowledge sees the ECU picture posted and can tell me if it’s the correct computer or not.
ECU and harness were bought from a guy running a D17A2 in his 02 EX.
what is different is that 03-05 uses wideband O2, narrow band for 01-02.
The rear O2 sensor is NOT hooked up. The plug is not long enough to reach. We can work around that, but that shouldn’t keep the car from starting, correct?
Im not a Honda guy but that looks like precat upstream sensor you got circled. Are you saying if I have a downstream then it’s not a A2 motor?
Sorry this is the upstream sensor. However A2 has both sensors under the car. see this video.
I don't know if you can mix A2 engine block with other exhaust.
Sorry this is the upstream sensor. However A2 has both sensors under the car. see this video.
I don't know if you can mix A2 engine block with other exhaust.
-Shouldn't be any issue using the A1 exhaust with the A2 engine. May not make as much power but that's it.
-When I look up your ECU part number it says it's for a 2002 EX so you should be okay with the primary 02 sensor.
-In another thread a few weeks ago we figured out that jumping the fuel pump relay will not bypass the immobilizer.
When you turn the key on does the green key in the cluster come on at all? Should come on for a few seconds then go off. During this time you should also hear the fuel pump run for two seconds then shut off. If that checks out have someone crank while you're checking spark. We have to figure out what's missing before we can troubleshoot why.
Excellent. No there is never any green key illumination in cluster. I tried to hook up my OBD2 code reader. I assumed if it says all clear then ECU is ATLEAST being detected. I am getting a link error, do you think the ECU could be bad? I will do a little looking around to find out if the fuel pump is turning on or not and report back.
The strangest thing to me is that it runs on non-VTEC ECU but won’t even start with VTEC ECU.
No there is never any green key illumination in cluster.
That is suspicious. Check fuse number 9 (10 amp) in the under-hood fuse box. That makes me think the immobilizer system isn't powered on at all which would definitely prevent starting.
Originally Posted by MattH
I tried to hook up my OBD2 code reader. I assumed if it says all clear then ECU is ATLEAST being detected. I am getting a link error, do you think the ECU could be bad? I will do a little looking around to find out if the fuel pump is turning on or not and report back.
The strangest thing to me is that it runs on non-VTEC ECU but won’t even start with VTEC ECU.
Usually when a code reader fails to communicate it is caused by a loose alternator which can fry the ECU. Possibly you got a bad one? Check engine grounds as well.
That is suspicious. Check fuse number 9 (10 amp) in the under-hood fuse box. That makes me think the immobilizer system isn't powered on at all which would definitely prevent starting.
Usually when a code reader fails to communicate it is caused by a loose alternator which can fry the ECU. Possibly you got a bad one? Check engine grounds as well.
I also jumped the fuel pump relay (blue one behind glovebox). Still no start!
The immobilizer disables fuel and either ignition and/or the injectors. Jumping the fuel pump relay does nothing except verify the pump works.
Originally Posted by MattH
Engine grounds are all okay, also remember car runs a small drives like a CHAMP on non VTEC ecu.
If you put in the original ECU and change nothing else it starts and drives still?
The immobilizer light not coming on makes me think the system isn't powering up either. It could just be a burned out bulb but the fact that you said the fuel pump isn't priming and you can't talk to the ECU with your scanner indicates bigger issues. I know you said you checked the engine grounds but check G101 again (see below). Comes off the engine harness and grounds to the water passage/thermostat housing. Looking back through your pictures I can see the ground from there to the radiator support but not the one from the engine harness. The troubleshooting for the immobilizer light not coming on is also below.
The immobilizer disables fuel and either ignition and/or the injectors. Jumping the fuel pump relay does nothing except verify the pump works.
If you put in the original ECU and change nothing else it starts and drives still?
The immobilizer light not coming on makes me think the system isn't powering up either. It could just be a burned out bulb but the fact that you said the fuel pump isn't priming and you can't talk to the ECU with your scanner indicates bigger issues. I know you said you checked the engine grounds but check G101 again (see below). Comes off the engine harness and grounds to the water passage/thermostat housing. Looking back through your pictures I can see the ground from there to the radiator support but not the one from the engine harness. The troubleshooting for the immobilizer light not coming on is also below.
That is correct, if non vtec ECU is plugged into harness, car starts and runs. Car has been driven back and forth to work 400+ miles total since VTEC wire harness has been installed.
I’m not familiar with immobilizer systems, but at this point I’m betting on immobilizer malfunction, ECU needs professionally flashed to match key, or ECU is bad. Is there a way to permanently disable the immobilizer?
Excellent info and your response time is incredible! I will respond after I look around a bit, thanks again!
I checked the ground from the battery to the bracket on transmission and the ground from the harness to thermostat casing. All is good.
In troubleshooting the immobilizer, where is the immobilizer control unit receiver? If there was an open in the wire between fuse box and cluster there would be more wrong than just the green key light not working, correct?
Let me mention the car that we bought this harness/ECU from was in a pretty hard hit accident. Figured that may play a roll in some of this, not sure.
