Fired up my '97 Impreza OBS last night to leave work. Let it high idle for a few minutes. Put it in gear, gave it a little throttle, it goes forward for about 2 seconds then starts bogging down and wants to stall. I let off the throttle, idles fine, even idles in gear and will roll. Gave it a little more gas, again it went for a couple seconds then bogs way down, almost dies, I let off and it idles fine. This goes on for about a half mile and even stalls once. I can barely get any momentum. Finally I just park it in a parking lot and get a ride home. I was thinking the tranny was finally gone. It's had some erratic shifting issues since I bought it a few months ago but nothing this bad. So this morning I buy a bottle of ATF and a bottle of Lucas transmission repair. Fired it up, let it warm up to temp, put in half a bottle of the Lucas as it says, and it idles like a champ the whole time. Now I'm sitting in park, hold it at 1,000 RPMs and in less than 10 seconds the RPMs drop, it bogs down, and I let off the throttle so it comes back to idle. Then I hold it at 2,000 RPMs with the same result. Now I rev it to 3,000 and it's fine; holds 3,000 + RPMs with no bogging or anything. After farting around for a half hour I just put it in gear and go; drives as normal as it always has. I've only driven it about a half mile though. Best guesses? =)
Yeah I was thinking IAC or TPS as well. Know where I could find the OHMs resistance values to check against? Maybe a How To on doing a sweep test and resistance test on the TPS? It is throwing a code for O2 sensor but it's been like that a couple weeks now; had my share of failed O2 sensors and never a problem like this.
Vacuum leaks effect the idle as well but this thing has a rock solid idle. Valve train does make a little noise. Some chatter from it before it's at full temp. Ordered an O2 sensor and Knock Sensor; I'll be putting those on tonight.
After work it behaved itself; no problems and I hadn't really repaired anything. Last night I did the O2 sensor and knock sensor. Taking special care to make sure the knock sensor was at the 45 degree angle. Everything seemed normal this morning and the CEL stayed off. I guess it's fixed.... for now =P
