TMan91

Hi, all. This is a long post, but I'm trying to be as informative in regards to what happened and what I've done as possible, so please do bare with me.

So, I have a bit of a problem. My 98 Integra GS with the original B18B1 in it was doing fine up until the other night when I was traveling down Chippenham following my friend in his tC to a local meet spot. I noticed that my headlights seemed dimmer than usual reflecting off his rear bumper. I then looked at my cluster and noticed it too had dimmed, as well as the A/C and heater controls and every other light on the car. I also noticed that my speedometer and odometer had stopped working. Finally, the Check engine light began flashing, followed by the ABS light, which after a few seconds started flashing, followed by the SRS light, but no battery light. I know it is something power related. On a fully charged battery, the car runs strong and healthy, but after 30 minutes of idle, it begins to lose power, the tach starts bouncing around and those same cluster lights come on in the same sequence again and again.

Now before I go any further, let me say that this happened 3 days after my catless test pipe was installed. I already checked the upstream and down stream O2 sensors to see if they had been severely twisted and/or were showing or touching bare wire and they are fine. I checked all my grounds as well and they are all good. I have thoroughly cleaned all contact strips inside of all connector clips all the way down to the IACV, TPS, MAP, and CPS, and all other clips that exist on the harness. All were fine.

I went ahead and tried the famous "Alternator Diagnostic" of jumping the car, letting it run for a few to warm up, then having a friend rev to 2k while I pull off the negative battery cable. When we did this, the car instantly died as soon as the negative cable was disconnected, which tells me that the alternator was not getting power to the ECU and the car was running solely off of battery power. Seeing that it is mandated by Federal manufacturing laws that every vehicle produced in the US must be able to run off a secondary power source, the car should stay running when the negative terminal is disconnected, as the alternator should be powering the car with the battery as a secondary as soon as the need for extra energy is met.

I went ahead and pulled the old original alternator out thinking that the diodes had failed. Took it to AutoZone and had them test it. Results came back that diodes were good, voltage regulator is good, and overall, it passed with flying colors. However, being that their external tester doesn't put a heavy load on the alternator, I assumed the worst and replaced the alternator. Even after a brand new alternator, same thing, same sequence, but the speedometer and odometer never did start working again. Then figured "Maybe the battery dropped a cell", so I replaced the battery as well. All was well, then again, same exact thing happened AGAIN! I then decided to plug in an onboard global diagnostics tool to the car and pull the codes. The codes were one for fuel trim bank 1 (Knew that was going to happen since I have a Walbro 255 pump, injectors, and test pipe), one for "A/F Heater Circuit High Voltage Input" (Which is why I assumed that somehow current was sent the wrong way, burning out the diodes), then another for "ABS Vehicle Speed Sensor High Voltage Input". I would provide the actual code digits, but I have since lost the piece of paper that I had written them down on.

So I am stumped. I heard that it might be an "Alternator Fuse", but I'll be danged if I can find it. My fuse panel cover has no diagram on it from years of being in the trunk and years of sun bleaching, so I have no idea which fuse I'm looking for. I do know that this fuse is said to also be tied with the VSS (Vehicle Speed Sensor), which would explain the speedometer and odometer not working shortly before this fiasco happened.

I would greatly appreciate it if someone could tell me where this fuse is so that I can check it and ensure that it is indeed bad. My only other question would be this... What in the actual world would cause that fuse to blow and cause those codes if I didn't have any short circuit situation? More than anything though, if anyone has a 1996 - 01 Integra GS fuse box diagram, or knows the location of the Alternator / VSS fuse, PLEASE let me know immediately. Also, if you have experienced a similar problem, please let me know what your findings were, as they would help me out in my quest to fix my car.

Thanks!
-Terence.

TMan91

****EDIT****

Disregard! Found the fuse and the issue. The wires running up through the floorboard and under the drivers seat for the Down-Stream O2 Sensor had been worn out and twisted, causing bare wire contact in which they created a circuit and blew the fuse. Replaced the entire sensor (Which was not reading correctly anyways), replaced the 7.5A fuse, and now speedometer works, alternator is providing full input to the car and the battery again and life is good! Thanks anyways, guys!