I'm looking for a little insight here. My '97 Formula has been tossing off SES lights since I got it a month or so ago.

I currently have the following codes stored:
P0171- System too lean (bank 1)
P0013- Exhaust camshaft position actuator circuit/ open bank (no idea what that is- didn't turn up on a search here)

And I have these codes pending:
P1351- Ignition Coil controll circuit high voltage
P0002- Fuel Volume Regulator Controll Circuit Range/ Performance

The car is a 6 speed with 80K miles and no mods. It test drove like a dream and then lost the opti within 200 miles.

I replaced that and damaged the ignition coil weatherpack connector in the process. After fruitlessly replacing the OEM ignition module and coil, I repaired the connector. I kept the old coil and module and left the Autozone replacements on ( I know, I know... but I was desperate to get the car moving and the store was near bye.) The car ran so, so. A couple of days later I was looking around under the hood and saw I never reconnected the MAF or IAT sensors (Doh!) I hooked them up and went to the track to run a blistering...16.3@89mph. Back to the drawing board. Had a P0100 code. Troubleshot the MAF back to the 20 amp fuse servicing the MAF and all 4 O2 sensors. I guess that it shorted while dangling free under the hood afetr I forgot to hook it back up. Replaced the fuse and realized true joy: I could force the car into TCS management by downshifting and punching it with abandon... at a 60mph roll!

The car ran great for a week or so. At that point I added Moroso Blue Max Wires and new NGK TR55 plugs. The car ran even better for about three days, when the #6 plug wire finally burnt through ( I had it too close to the manifold; I just did a bad job of getting it tied out of the way.) SES light came back on and the car missed badly.

I have since replaced the #6 wire with the original GM 7mm (which tested out fine- certainley better than the fried Moroso unit.) After doing this I reset the computer and drove the car. I made it through about 5 minutes of idling and a 1/2 mile of driving before the SES came back to taunt me.

And that is where I am now. I got the codes using my AutoEnginuity scanner. I think I need a 3rd party opinion here. Any help or ideas would be appreciated.

Thanks.

 

Those codes don't look right.... there are no codes under P0100 for the OBD-II LT1's. There is no such thing as a "Exhaust camshaft position actuator circuit", or a "Fuel Volume Regulator Controll Circuit " on an LT1.

The "lean" code is frequently caused by:

-exhaust leak before the O2 sensor
-misfires
-faulty sensor

 

OK, so tossing out the 2 codes below P100, I have a P0171 that is stored and a pending code that I think I can ignore for the time being. So I'll concentrate on that.

A bad O2 sensor seems to go along with the driveability issues I have. On cold start-up and at WOT the car runs strong as hell. Once it is warmed up I get the SES light flashing at me under heavy load, light throttle conditions (going up a slight grade in 6th gear at 70mph).

I can try swapping O2 sensors out. That's simple enough. I have the abiltiy to watch real-time O2 voltage or fuel trim % values on any of my four sensors. What kinda info would I be looking for here?

 

Only the "pre-cat" sensor can set the "lean" code, so you need to concentrate on the readings for the Bank 1 pre-cat.

But, you need to consider the other possible causes of the "lean" condition also.

When you hook up the scanner, take it for a drive. Observe the fuel "cell" number, and the corresponding long term fuel corrections, both left and right banks for that cell. Get as many of them as you can, ranging from Cell 16 at idle, the low load/rpm cells like 02, 02, 04, and some high load/rpm cells like 14 and 15. One or more of those long term fuel corrections will be max'ed out at 160. That's the cause of the code. Or, the sensor is stuck at a very lean level, and isn't moving... e.g. 0xx-3xx mV.

The after cat sensors can't set a "lean" condition because they are just there to tell the PCM if the cats are working. The after-cat sensor mV's track the swings of the pre-cat mV's, but over a much narrower range, closer to 450mV.

Have you read this:

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

If the SES light is flashing, you should also be getting the random misfire code (P0300), or some cylinder specific misfire codes. Using the scanner, look at the misfire counts for each cylinder. That will tell you which cylinder(s) is missing.

 

OK. First off, great link. I especially like how you boiled down the MAP explanation. Simple without overstating things.

The scanner I have is not a Scanmaster. If anybody is interested, this is it ( I have the Palm version):
http://www.autoenginuity.com/

I just got it, and don't yet know if I can check individual cells. What I can do is look at either primary O2 sensor info and short or long term fuel correction values as a % of the base programming. I can also log the data and save it in a few different formats. So I'll spend some more time looking at it while driving under different conditions this weekend.

The only thing that is really making me go ape is that no misfire codes are being reported, although what I understand is that a flashing SES means ther is a misfire. It's just one more thing to look into. Time will tell.