After months of troubleshooting and pulling my hair out, with computer programs and such, I finally fixed my knock problem. I always got knock and stumbling in the car, up to 16 degrees at first at part throttle about 2-5 at WOT.

I tried to disable the knock sensor with a resistor, didn't help. i sent the PCM to madz28, he disabled all the knock sensor values in the PCM and it went from 16 degrees timing pulled at part throttle to 8 degrees at part throttle, 0 degrees at WOT. But it still pulled timing and no one had an answer for me. I emailed Ion a few times back and forth no clue.

I changed the entire ignition, the 02 sensors themselves, and various other sensors made no difference. I then forced the car to open loop by disonnecting both 02 sensors, and guess what, no knock retard at all. And the car runs 10 times better, almost all major stumbling is gone.

So, this leads me to believe I have some shotty wiring between the 02 sensors and the PCM, this can be due to my header heat, and/or my tapping into the signal wire for my A/F guage. I have to examine all the wiring now.

So, just FYI, screwy signals from an 02 sensor can cause your PCM to pull timing no matter what you do to the PCM to disable knock retard.

Brian

 

Hmm... thats interesting. I'm having sort of the same problem with retard. I might try this.

But I wonder why would the PCM pull timing with no knock? Even if a LEAN condition if detected, it will throw a SES light first.

I'm trying to tune each cylinder individually with a temp gun, it seems like 3&5 and 4&6 are running 100 degrees hotter than the rest... but I think it might be because the primaries are next to each other...

Alot of tuning to do...

 

Hey ZPaul2Fresh8 what temp numbers are you getting? and what headers and are they coated? very interested as i was trying to do this also and was getting big differences like you said. Hawk, thats good to hear, ive been following your problem for awhile now, glad to see you finally figured it out, now just to fix it

 

Off the top of my head They were something like this:

Bank 1:
1: 160*
3: 270*
5: 270*
7: 160*
Bank 2:
2: 150*
4: 280*
6: 240*
8: 160*

Now this was after I let the car idle for about 20 minutes or so. They are Dynatech Longtubes with coating (BTW isn't the best coating, need redone)

But as you can see there definately are some differences in cylinder temps. A more accurate way would be to buy some header wrap and cover each one so the exsisting heat doesn't cause false readings.

 

Does the CPU take out timing when the SES light is on?

 

I think it has more to do with the fact that the exhaust valves and ports are right next to each other moreso than just that the primaries are next together.

I saw a thread in advanced tech about tuning spark for individual cylinders... lemme find it.

 

Unsure, haven't had the light while logging. I would say NO, that is what the knock sensor is for. If you get a "Fuel system lean" code, you'll probably get some knock under a load,

 

No, when the SES light is on the timing stays the same.

I've unplugged almost every sensor on the car had like 8 codes, hehe, no timing was being pulled.

The only O2 code I ever got while troubleshooting my car was one that read "transition time" error or something. I never got rich/lean codes or an actual 02 sensor failure code. I know my car was running rich cuz my gas mileage really blew and the car would backfire, and sometimes I could smell fuel.

Anyways, I'm happy my car is finally running like a champ can't get traction in 1st or 2nd again Time to fix the wiring and hook up the juice

Brian

 

Oh, Someone was telling me that when the light is on the cpu goes into limp home mode and takes power out?

 

My 96 Formula has always had a tendency to pull timing, even without increased knock counts showing on Autotap, even basically stock.

Even now, it shows pulling some timing (small amounts < 1 degree) when just maintaining and slowly accelerating.

 

That's interesting, but I think your problem is not with the O2 sensors...
If you simply unplug your knock sensor, or there's no ground, the PCM will pull max allowed knock retard, but only after it enters closed loop!
So my guess is, your wire going to the KS or the sensor itself is bad, causing you to pull timing in closed loop.

By unplugging both O2's you are running in open loop now, all the time (no KR).

Just my $.02

 

nope, I've had it disabled through programming by madz28. Also, before that, I've tried to replace it with a resistor, I bought another knock sensor and hooked up up and installed it out of the block(yes I put on a ground wire). I also ran it disconnected to see if that made a difference. NO matter what I tried the knock stayed the same, and if it's disabled in programming there is no way the knock sensor can couse timing to be pulled, so thats what I'm saying here. It has to be something else.

Also, I'm pretty sure the knock sensor is used in both closed loop and open loop, just the 02 sensors are added when the car enters closed loop from what I understand.....

Brian