orangecivicsi

My friend and I recently purchaced a 2000 honda civic si. It has a factory B16A2 in it and the guy that had it before thought he would try his luck at some wiring on the ecu. well needless to say it didnt turn out very well. It has been burning rich since day 1 and we have been troubleshooting since day 1. The cel code is P0108 hich is M.A.P. sensor high input low vaccum. Only thing is the vaccum is perfect and the M.A.P. sensor is also. I found a couple of the wires from the ecu to the sensor were chopped so i twisted them together and shrink wrapped them. The car is still burning rich so far was hoping someone had this problem before and can give us a heads up on what they did to fix it. Oh, and i have continuity from all 3 wires to all 3 pins on the harness going into the ecu.


Modified by orangecivicsi at 10:42 PM 6/5/2007

ABK

Car prolly had a VAFC hack on it. Somebody didn't know how to take it out properly and messed it up. Get a wiring diagram and make sure wires go where they are supposed to go on ecu side. Worst comes to worse get a new harness. Shouldn't be more then $100 used if you look around hard enough.
Or you could just be desperate and completly rewire from map sensor to ecu.

orangecivicsi

Do I have to get a 1999-2000 Honda Civic SI harness or can i use another 1999-2000 harness such as another civic with VTEC? Also, if i decide to go the rewiring route can i cut into the old harness and just soder (not good at spelling) and shrink wrap or is there a place i can get new ends to go into the connecters?

blackKready

any 99-00 civic with vtec should hook you up. integras are different , although the same.

blaze the chemi

I would help you, but I left my helms at home. There is a complete troubleshoot in the book for your situation. I'll try and help you out tonight if no one else chimes in. It's been a while since I've been down by the ECU. I can't remember the wires exactly.

klungemonger

If it comes down to replacing the harness I would save yourself the hassle of using anything other than the 99-00 Si version. The EX 5-spd is the only other one with all the same connections but some branches are located differently and you'd have to modify them to fit. Plus you aren't going to save much money to justify hacking it up.

orangecivicsi

When i re-connected the wires and shrink wrapped them i didnt use the solder (again...i should look that word up) on the wire underneath. The guy did have something aftermarket on the harness because he bared some wires and had other cut wires connecting too the bared wires going to the ECU that were just dangling there. I bought the car from a dealership so I have no idea who the previouse owner was. Would make life easier if i knew what the heck the guy did too it. I have the harness almost all the way out because the person who owns it want to make sure it is all good. If it is too bad he is just going to spend the 400 or 500 bucks and get a new one.

klungemonger

You can get good used ones on Ebay for $150-$200 on the high end.

orangecivicsi

I looked there last night and they didnt have any 2000 Honda Civic SI wiring harnesses

klungemonger

Well I don't know how you searched but I found these ones in 3 seconds...

http://cgi.ebay.com/ebaymotors...ZWDVW

http://cgi.ebay.com/ebaymotors...ZWDVW

http://cgi.ebay.com/ebaymotors...ZWDVW

http://cgi.ebay.com/ebaymotors...ZWDVW

blaze the chemi

The MAP has three wires
1: Yel/Red that goes to C19 on the ECU, this is the reference voltage
2: Red/Grn that goes to C17 on the ECU, this is the input from sensor
3: Grn/Wht that goes to C7 on the ECU, this is the ground.

Hopefully the previous owner didn't switch the wires, but I highly doubt that because your car would be running like poo otherwise.

Get a scan tool and conduct the following:
Step 1. Let car warm up and let it idle. Does the MAP read 30 in. Hg or higher?
yes- go to step 2 no-intermittent failure

Step 2. Turn car off and disconnect MAP sensor. Get a paper clip and jump term 3 and 2 on the connector. Turn ign on (II) Check MAP with scan tool. Again, is the MAP read 30 in/ Hg or higher?
yes- goto step 3. no- replace MAP

Step 3. Remove jumper wire and measure voltage on connector on terms 1 and 2. Is there approx 5 V?
yes- go to step 4. no- repair open between C7 (ground) and MAP

Step 4. Ing off. Make jumper between C7 and C17 and turn ign on (II) Check MAP with scan tool. Reading 30 in Hg?
yes- get another P2T ECU and see if problem goes away. no-repair open between C17 (input) and MAP

Good luck. The C connector on the ECU is blue if I recall. It's next to the empty slot where the automatic sensors would plug if the Si were auto

ABK

Do not ghetto rig ****. Either put in the whole harness or fixed the map connections on the other. Either job is not hard. Don't just and solder on the piece of the harness. You will cause yourself too much headache.

Replacing the harness is easy. EX one will work, just extend couple of wires here and there and you are done.

orangecivicsi

The troubleshoting guide that was posted is the same one i used. The map hg was between 11 and 26 which is where we found the wiring issue at. I managed to get the rest of the harness out last night and found thatthe other owner plugged some vaccum lines ( very poor blocking job ) so when i fixed the wires to the ecu it blew one of the vaccums he blocked off thus creating the same problem but only low vaccum now. I am going to solder and shrink all the bare wires and figure out where that vaccum is supposed to go to. I will post more when i get it figured out. Oh, and for everyone that made the good suggestions thanks. I am sure it helped someone out.

orangecivicsi

Well i have some good news. After fixing the few wires on the harness that go to the map sensor it fixed it for the moment. As soon as i started her up it made a vacuum leak. After repairing that i found it was still burning rich. So after some lloking around i realized the guy had a regulaor on the passenger side of the fuel rail and had the pressure boosted all the way up. so after re-adjusting that we took it for a test drive and all i have to say is wow. The vtec kicked in right at 5500 and it gracefully jumped up to 120 MPH as if it was nothing. so after the major problems from that i have more. Ill probably have a new post on here for some more help tomorrow. Thanks everyone for all your help and taking the time to read and answer my forum.