kgkern01

I've had an SES light for about a month since the new trans and clutch, and Sat night I finally got WOT a few times on the xway then it started running as if on 7 cylinders. Now runs that way in open loop on startup too. Finally got a laptop yesterday and scanned w/DataMaster and got DTC 13. So does this mean my driver's side O2 was bad?
Also, would that have caused it to run very rough like it is now?

SC/TA

If the light came on after the trany swap, it could just be a loose connection where the o2 sensor plugs into the harness. If it has came unhooked that would explain the rough running. Also make sure the o2 wires haven't touched the exhaust anywhere. It could have burned the wire causing a short.

kgkern01

I'll check the connections. My other question is if it just a bad O2, why is it running real bad on startup and open loop as well? Fouled plugs or something else?

kgkern01

The SES light was a loose O2 connection. Replaced the plugs on that side also. Still runs terrible. Also has a loud tick. What could it be?

BlazinREDZ28

I just got through fixing my car. It would idle rough no matter what. I had several problems but the final problem was my left o2 sensor. The car ran like crap from start up on. The reason yours has probably started to run rough is probably because the pcm has made changes, based on the information gathered from the faulty o2 sensor or bad wiring which every it may be, and the fuel trims are probably off. What was the long term fuel trim on bank1 when you used data master?

kgkern01

short and long term fuel trims are all 128.

Injuneer

In what cells, and open or closed loop?

kgkern01

I believe was closed loop because it had been running about 15 min before I scanned it , can't remember for sure though. All 4 fuel trim cells (L & R, short & long term) showing 128.

Injuneer

Then there's a good chance it wasn't in closed loop. If it was in closed loop, the short terms should be changing about 9 times per second, swinging above and below 128. If you have a dead sensor, it won't go into closed loop, and the short terms will remain fixed at 128. If at any time you were working on the vehicle you pulled the battery power, it reset the long terms to 128.

The circuit is open, either a dead sensor, a burned wire or a loose connector. What is the voltage for the driver's side O2 sensor?

A bit of extra info... there are 18 cells, each covering vairous combinations of RPM and engine load (MAP), plus idle, open loop fueling and decel. The "cells" contain only the long term (learned) fuel corrections. And each cell contains both left and righ long terms. Short terms are called that because they are used once and not saved. Your long term data is for a single cell, not 4.

Online scanning guide:

http://members.aol.com/InjuneerZZ/ScanMast.htm

kgkern01

So do I need to disconnect the battery to reset the PCM after the O2 problem is fixed to correct the rough running problem, or is it something else?

Injuneer

Resetting the PCM won't help. That will just return everything to "128", and if it runs poorly now at 128, its going to continue to run poorly in the future at 128. The idea is to get the O2 sensor problem fixed, then let the PCM go into closed loop and start "learning" the long term fuel corrections to put into each of the cells. That may fix the problem, or it may not.

Apparently you have had the O2 sensor problem for a while and the engine was still running OK. So the O2 sensor may not be the cause of the single cylinder misfire. The fact that it happened only after a WOT excursion may indicate a problem with a plug, wire, injector, bent pushrod, faulty lifter, loose rocker, damaged Opti rotor, etc.

Fix the O2 problem, and if it doesn't fix the problem (I'm guessing it won't), start looking for the cause of the misfire.

kgkern01

I also just noticed oil leaking from my timing cover. I bet the freakin opti seal is leaking! The opti has only been on a few months! I guess I'll check for spark at all of the plug ends first. Is there any way to detect for a bad lifter because of the ticking I hear?

kgkern01

Started this morning about 33* and while still missing, didn't start ticking until it got warm, getting louder the warmer it got. would that mean it may be exhaust related due to the missing?