Yesterday when I was driving the car I came to a stoplight before it had completely warmed up and it shook while idling. Once I got moving it didn't shake anymore and didn't shake again until today. I started driving before it was completely warm and this time it was shaking under normal acceleration. When I came up to a stoplight it still shook and the exhaust was popping too. No pattern to it, just kinda popped here and there. It was idling lower than usual probably about 600-700rpm or so then it surged up to about 1100rpm and the check engine light came on. The prompted me to check for a trouble code and the scanmaster read dtc 44.

I pulled over into a parking lot and checked the all the readings at idle. I didn't have anything to write with so I'm going from memory here:

MAF - 6 (normal for my car)
SP - 40 (usually 20-22. It seemed to slowly go from 40 to 30's to 20's then back up to 40 for a while)
LP - 4.0 (usually ~1.3 It did the same thing the SP did, sometimes slowly move down then go back up slowly and stay)
rP - 1.3
dtc - 44 (O2 sensor lean. Could be bad sensor, wires, vacuum leak, low fuel pressure)
LBL - 160
rBL - 108 (while driving, these would do the same thing the LP and SP did above, move slowly toward equalizing then go to crap again)
CEL - 16 (under my *extremely* light acceleration on the way home I noticed CEL 18 while cycling through the readings)
Lin - 122 or 136 and it did not move at all
rin - can't remember the number, but it didn't move
O2L - it was either up between 800-900 or between 100-200 and didn't bounce between any other numbers. Not the usual 100-900 range.
O2r - it was either between 400-500 or 200-300 and didn't bounce between any other numbers just like O2L
IAC - 70 (usually 40)
MAP - 8.7 (usually 9.0)

So there they are. While sitting there at idle, it shook and popped like before. I didn't see, smell or hear anything different under the hood or inside the car. The exhaust smelled extremely rich, or maybe it was oily I can't quite distinguish, like a lawnmower.

Once the car warmed up the symptoms were the same. SES would go off and come on. The readings wouldn't go back to normal with it off but they did improve slightly. Please help, this is my dd! (odometer just hit 198,000 miles btw)

 

Just watched it idle for about 15 minutes. It seemed to start having problems once it warmed up. The numbers would quickly get as bad as mentioned above. It would shake, the exhaust would pop occasionally. I noticed a few things, the pen I had ran out of ink so going from memory again here:

The IAC was higher this time, at 49. The MAP was higher too, at 10.4. The O2L was bouncing around from 100-900 like normal, sometimes staying high, but not like before. O2r was low, either between 100-200 or 200-300. Not 100-300. If I tried increasing rmp's, all readings would get worse and stay that way. It gave a couple good pop's when I let off the gas from 2000rpm too. Once the engine surged 100rpm's or so and the SES light went off but the readings didn't change. After a few minutes they went back to normal and the car felt and smelled like it was running fine. After a few more minutes it went to crap again. Look out the windshield with the hood up I could see heat coming off the engine and even smelled a little coolant when I went to take a look but the engine temp never got above 190*

 

Something wrong with the fuel control on the left side of the engine. The PCM has jacked up the left side long term fuel correction (LBL) to the maximum possible value (160 = +25% extra fuel) and its still running lean on that side. The left side pulse width is jacked up in response to the apparent lean condition. From the misfiring and the heavy fuel smell, this may be a "false" lean condition, where something is making the left side O2 sensor indicate the engine is running excessively lean, when it really isn't. This can be the results of a faulty O2 sensor, faulty wiring, exhaust leaks before the O2 sensor or excessive misfires. If its due to a misfire, the O2 sensor picks up the air that isn't being used to burn the fuel, tells the PCM its running lean, the PCM pours in extra fuel that side of the engine doesn't need, and now you have one cylinder misfiring and the other three running pig rich, and probably starting to misfire as well.

The long term for the right side (RBL) is going the other way, bottomed out at 108, the lowest it can go. That means the right bank is having 15% of the fuel pulled out, to correct what it sees as a rich condition. What you have is "split" long terms. You have to track down the cause.

You also need to familiarize yourself with the "Cell" concept. Cell 16 is used only at idle. Cell 18 is used for open loop acceleration. Cell 17 is used for deceleration. The cells from 01 to 15 are used for various combinations of RPM and MAP. Each of the cells has its own stored left and right block learn multipliers (BLM's). As you vary the throttle and RPM, the Cell is going to move through the grid of combinations, and the BLM's are going to change as it moves to another Cell. That's why they are changing as you drive.

The disadvantage of the ScanMaster is that it can only show you one Cell at a time. You could run through various combos of RPM and MAP, and try and jump back an forth between the Cell and LBL and RBL screens, but that's pretty awkward to do. Scanning software, with data logging capabilities makes it a whole lot easier. For the cost of a cable, you can data log your PCM using FreeScan (toatlly free) or TTS DataMaster (first 20 uses free). That way you can drive around and vary the driving conditions, to record as many of the Cells as possible. That may give insight into the cause of the problem.

If its in closed loop, the O2 reading should never be in a narrow range. They should always be cycling from below 100 to over 900. If the sensor is sitting in a narrow range, its either indicating a "true" lean or rich condition, or a "false" lean or rich condition. The trick is to figure out which it is. The fact you have a heavy fuel smell in the exhaust would tend to indicate at least the left bank of the engine is experiencing a false lean condition. If its severe, the excess fuel may end up in the oil and start to dilute it. Check to see if that is happening (fuel smell in oil).

"Split" BLM's generally result from a moderate to large cam, or an aftermarket throttle body. Since you don't have either of those, is sort of odd for it to occur.

For more detail on the Cells, and how they are used, read the "A/F" section of this:

http://www.injuneer.com/ScanMast.html

 

Sounds just like what mine does when it gets warm or you beat on it a little while.

 

I swapped O2 sensors to see if the readings would swap along with them. When I pulled the passenger O2, it looked brand new, totally clean. When I pulled the driver O2, it was black. When I started it with the O2's swapped, the passenger side varied from 100-900 and the driver side wouldn't go above 300 and didn't move around. There were pops coming from the driver's side header while it was idling. All the other scanmaster readings were the same. The driver's side was maxed out at 160, and while it was idling, it did another one of its small surges and the passenger side is now maxed out at 160 and I have a dtc 64 with the 44. I replaced the driver's O2 (the one that was clean and originally from the passenger side) with a brand new O2 and nothing changed. The readings don't vary.

So now both banks are maxed at 160. Why didn't the new O2 change anything? Is it possible my luck is horrible and I bought a bad O2? I suppose it could be the wire, I'll check that with the voltmeter. Why is my IAC so high?

I took out the PCM BAT fuse to clear it and I'll see what happens after about 20 minutes. This sucks.

 

Sounds like its running so horribly rich that the IAC has to open up more to try and keep the RPM's up to the specified idle speed.

 

After starting with the PCM reset, O2L is reading 003 and O2r varies between 0-100. The exhaust is still smelling rich and the oil kinda smells like gas too I suppose. There isn't any smoke or anything. That's all for today, I'm taking it to a shop.

 

A steady 003 mV would indicate either the PCM has not switched into closed loop, and the AIR pump is still running, or the sensor is shorted to ground. Doesn't sound like the other side is in much better shape.

 

As I drove it this morning, it started misfiring as it warmed up and presenting the usual symptoms. This time rBL was at 160 and LBL was at 108. All readings were the same as the first set except right and left are now reversed.

 

Just tested the O2 wires. Both had the same readings:

Gray: 1.56v
Black: 0.0v
White: 0.0v
White: 12.53v

I'm going off the colors on the sensor itself, not the wire it plugs into since those are too dirty to tell. Are these normal?

I'm gonna check the grounds.

 

I tested two grounds, one on the front of the engine on the drivers side and one above the k member on the passenger side, they were good. I swapped PCM's and fired it up, O2L is still at 003 and O2r is staying below 100, both banks are maxed at 160. It was actually idling normal with the scanmaster reading normal values except for the O2's until I gave it some gas then it quickly started to idle like it had a huge cam, the exhaust was burning my eyes and nose, and all the readings went bad. Please Help!!!!!!!!

 

You can't keep running it with the fuel pouring into it like that. The oil is getting diluted with fuel and you are going to see bearing damage.

The wire colors you noted on the sensors do not match the factory O2 sensor colors. Look at Shoebox's PCM wiring diagram, pcm2. Tan is the signal ground, purple is the signal positive, black is an engine ground, and pink is the heater 12V power supply. All sensor wire colors show the same as the harness wire colors, except for the heater power supply - brown harness wire connects to pink sensor wire. Appears someone may have swapped in a different brand sensor.

Also bad to probe the wires that connect to the sensors, or to the PCM, since using the incorrect multi-meter can damage both.

Hard to follow the sequence of events.... you had (post #1) 160 left, 108 right. You swapped O2 sensors the first time (post #5), and you got 160 left and 160 right.
Then you drove it (post #9) the BLM's had swapped, 108 left, 160 right. Seemed to indicate the long terms followed the sensors. Then in post #11, both banks are now max'd at 160.

Doesn't match anything I've ever seen. There would appear to be an intermittent short in the wiring, coupled with faulty sensors. But that's just a guess. Can't think of any other reason that would have the BLM 160 one day, 108 the next day, 160 the next day... etc.

 

The block ground is only for the heater element power. It has nothing to do with the signal portion of the sensor. The PCM supplies both the ground wire and the signal wire for the sensing portion.

 

I checked the ground on the block that the O2 uses and it was good to go. I'm stumped. Thanks for all your help Injuneer I really appreciate it. Now it really IS going into the shop.

You've got the order of events correct. I don't have the knowledge or patience to go digging around my wires, chasing down a short. I probably shouldn't have done all the stuff I already did.

 

This is the last ground I checked: http://shbox.com/1/g103.jpg

Also checked:

http://shbox.com/1/battery_cable_ground.jpg

Couldn't find a pic of the PCM harness grounds but I'm sure you're familiar. I was wanting to check all the grounds in the PCM wire circuit, I thought there were some under the dash but the sun went down and I have bruises from rolling around on concrete all day so I'll save it for later.