js0616

i just bought a 00 civic si, and i think it has a low temp thermostat, so it takes forever to warm up the car, and when i start driving the temp goes down again. is it normal with the low temp thermostat? also the engine idles at 2000 or 1500 even after i drive the car for a while and rarely goes down to 900, or 1000. I guess being in such cold weather in ohio, this might not really help the situation. is it all because of the low temp thermostat? or is there something else that's wrong with it? and also i have a check engine light and the code read was p0131. would this cause the problem? please let me know.

Sean @ ESG

iTrader: (1)

I believe that's an o2 sensor code. Try taking a look at it, it may need to be replaced. Try replacing the spark plugs as well, make sure they are gapped correctly. May as well clean the IACV too. All those might help to smooth the idle out.

mwaedow

I'm having an idle issue with my B16A2 engine. I am running it in a '96 lx sedan, and in addition to the engine and SI harness, I have swapped the dash and cabin harness, so everything is obd2b now. I recently fried my ecu by incorrectly pinning the green cabin harness plug near the ecu, and had to purchase a replacement ecu. Prior to my mistake with the wiring, the car was running just fine. I had no CEL, VTEC functioned normally, everything. Since receiving the new ecu, I can't get the vehicle to run properly. When I start it, it dies out almost immediately unless I keep my foot on the gas. CEL comes on soon after starting, and it will only run on its own when I pull the cruise control vacuum line off the manifold so it can breathe. I know it's not good to run with a vacuum leak, but it will run no other way. Also, as I give it throttle, the RPMs bounce between 1100-1500 RPM. If I rev higher, it revs smoothly. I drove it only briefly around the block, and it was misfiring badly, bucking and bogging. my plugs are carbon fouled due to the rich condition. I have cleaned and inspected the IAC, and it appears fine. I ran power and ground to IAC, and the pintel moved as it should, so I am prepared to dismiss it as the culprit. I have run compression tests, suspicious of a head gasket leak, and compression is fine, about 210 lbs/sq. in. per cylinder. I have bled the coolant system, checked all fuses and relays, and have found no smoking gun related to my problem. Could this new ecu have been reflashed at some point, maybe for someone's turbo setup, or is it perhaps at fault in some other way? There are no visible damages or modifications inside the computer, but I still don't trust it. I would appreciate somebody to point me in the right direction.

mwaedow

also, I'm still unsure about the green cabin harness connector by the ecu. It's a 22-pin connector, but only utilizes ten wires. six of them are unique, but there are two solid green wires, and two green with a black runner. I don't know which to pin where, and I apparently had it wrong, as it fried my ecu, sent power to the wrong wire. I was missing speedometer, instrument lights, and my Data Link Connector won't communicate with the computer. Also, my cooling fan doesn't turn on automatically, I had to jumper it in the underhood fuse box to stay on at all times. I assume that this green connector controls most if not all of these things, but I had left it unplugged, not knowing if I had it right. Does anybody know for sure what is controlled through this connector, and how I can make sure I pin it correctly?

mwaedow

bump

mwaedow

bump again, please help, anyone?

mwaedow

bump

dale m.

mine did that recently but worse

i changed the spark plugs and plug wires
cleaned the iacv

was throwing an 02 code
cleared the code
and has been fine since and that was about 2 months ago

mwaedow

I tested the IACV connector plug for power and ground. I found power, which I believe comes from the main relay, but there was no ground present at the connector, which should come from the computer, correct? I stuck a paper clip in there like a t pin, grounded it to the battery, and my idle became erratic. Now what should that tell me? Is that a telltale sign that the IAC is bad?