Connexion2005

Ok. The other day I put on my LPP headers and Y as well as some new plug wires and a new starter. I took the liberty of re-routing the passenger side harnesses that run down to the starter, ks, grounds for the block and the ABS harness along with the o2 harness. I also re-wired a bit and cleaned things up as the previous owner used tacky strips of header wrap which looked ridiculous. Unfortunately in the process I must have been a tad rough with the knock sensor pig tail as it no long carries voltage to the end of the connector. I have voltage all through the wire (4.5-5v) but at the connector it is shorted. I've gone ahead and ordered a new pigtail off of eBay to wire in so I'm not worried about it. In addition to this, I have pulled out about 5 degrees of timing in my tables all over the place and set the maximum knock values to 0 to prevent the constant maximum retard that will occur when DTC 43 is set. Here are the symptoms I have been experiencing and I'm not sure if they are caused by this DTC or not.

1) It has been very cold here lately and the car runs very poorly until it hits around 145 degrees and it begins to straighten up a bit.

2) I pull a consistent 900mv on both o2's and they don't appear to be switching. These are brand new along with the upgraded heated o2 conversion I did during the process. They are getting voltage and correctly grounded.

3) My BLM's stay at a consistent 128 value without changing one bit during all conditions even though the car is running as rich as it is.

4) I had to bump up idle 200rpm in the tune to compensate as the car tries to slowly idle down to around 500rpm when coming to stops. Idle is set at 1000rpm for operating temp.

What I mean by rough running in the cold is that it is very stumbly and if I hold the car at 2,500rpm or so during the first few minutes of a cold start I can actually get it to pop a bit.

I'm just curious as to whether anyone has any knowledge as to whether this could be expected from the KS or whether I may be experiencing ignition issues. This happened directly after all of the mods I just listed. My opti is a genuine AC Delco unit w/ 3000 miles on it, the coil has been ohmed out within the past month and passed but my ICM has not been checked since most places tell me they can't check it. I may read up on checking it myself.

Thanks for any insight and I will be sure to update after I install my new pigtail this weekend so future DTC 43 guys can know to expect these issues.

nhill_05

900 mV would mean it is running very rich. You probably already know this but for those who don't 02 sensors are generators that produce 0-1V or 0-1000mV. 0mV=lean 1000mV= rich. Most cars should be around 450 mV or so. 02 sensors work best when heated to a very high temperature. IMO would guess that most of your problems are because of this. However, If the knock sensor was pulling a ton of timing it could also cause it to run poorly.

Connexion2005

Like I said though, I have the knock tables set to 0 so it pulls absolutely no timing right now. My question is what is the computer going to do with efficiency of the tune other than pull timing. I'm hoping it just dumps excess fuel to prevent a lean out condition. I will see when my new pigtail comes in.

94Firehawk161

If the O2 is reading "full rich" then the PCM will most likely start pulling fuel (leaning out).

Connexion2005

Guys I know how the pcm should work. I'm asking whether anyone has thrown the DTC 43 code and driven around and to whether the symptoms are normal from it. Sorry for being blunt but I'm not looking for answers as to what my conditions mean but as to if they stem from the DTC code. The pigtail will be here in a couple of days so I'll report my findings.

Connexion2005

Little bit of an update here. The temps here have gone from 25-30 degrees to around 45-60 degrees and the car does incredibly better on cold starts. It is simply something that affects the car when it is at or below freezing. My Ls1 would slightly do it as well when it was extremely cold. I just don't know what it could be. I'm going to look at my tables for that temperature and see if that's what it may be. As far as the richness issue, I believe that will be settled with the new KS pigtail.

Connexion2005

Weather is back up to around 60 degrees at a minimum here and the car is performing outstanding. Hopefully the pig tail will be in soon and I can report on the o2's and blm situation.

marshall93z

When this DTC sets on my car, it won't even start without me holding the pedal to the floor. And runs like sh*t when you get on it pretty hard.

Connexion2005

Sorry for the delay but here is the follow up:

The pigtail came in and I crawled under the car to crimp in the new pig tail. Tested for 5v at the connector and all was good. The code has not tripped since these issues. Here is the summary:

1) It has been very cold here lately and the car runs very poorly until it hits around 145 degrees and it begins to straighten up a bit. (THE CAR HAS NOT SEEN THIS ISSUE SINCE THE NEW PIGTAIL. BELOW FREEZING IT WILL STUMBLE MAYBE 15 SECONDS MAX AND IT STRAIGHTENS UP BUT WITH THE TUNE AND A 383 I'M NOT SURPRISED AT ALL WITH THAT.

2) I pull a consistent 900mv on both o2's and they don't appear to be switching. These are brand new along with the upgraded heated o2 conversion I did during the process. They are getting voltage and correctly grounded. (THE O2'S COMPLETELY SWITCH NOW. IT'S CLEAR THE TUNE IS STILL RICH BUT THEY BOUNCE AS EXPECTED.)

3) My BLM's stay at a consistent 128 value without changing one bit during all conditions even though the car is running as rich as it is. (BLMS REACT TO CONDITIONS AGAIN. THERE ARE NO CONSTANTS AS YOU WILL SEE WHEN DTC 43 IS THROWN.)

4) I had to bump up idle 200rpm in the tune to compensate as the car tries to slowly idle down to around 500rpm when coming to stops. Idle is set at 1000rpm for operating temp. (A GOOD IDLE HAS BEEN COMPLETELY RESTORED AFTER THE PIGTAIL INSTALL)

Basically, if you are throwing DTC 43, you WILL experience these issues. The car will stumble and run terribly do to an extreme rich condition caused my interference with feedback from your oxygen sensor system and it will run even worse if your knock tables are not set to zero since maximum knock retard will be enforced allowing you to in some cases barely run. So, if you are throwing a code and experiencing these symptoms, here is your answer as to what to expect.

Thanks for all replies in the thread and happy holidays...

Josh

speedracer2j

My car was running without this knock sensor working for two weeks. My terminal was also busted. All i did since it was a saturday, and I was leaving for Iraq again Tuesday, was soldered a wire, on the connector inside the sensor, and used spade connectors to link it with the harness. Worked just fine. I experienced no real side effects, although I was ensuring the car had 93 in it only. I ran datamaster while the sensor was off too, and it was not pulling any timing out, although I never ran the scan with the sensor back in, so maybe I was losing timing? I believe it was still running at about 44-46 degrees advance at WOT. These symptoms you are reporting I had no experience with in my car, with DTC 43 present. I really didn't notice too big of changes with or without the sensor connected. But, my datamaster also showed very rich readings during this time, upwards of 900 at WOT. I blame that on lack of a dyno tune. Ill see if I cant get my buddy to run a scan now that all my codes are fixed, and see what I come up with.

Connexion2005

You still had some sort of connection present though possibly allowing you to get around the issue? Also I'm sure a tune with a small knock retard would have helped. I'm willing to bet your 900mv readings were from the code being thrown...

Injuneer

Data logs I've reviewed with DTC 43 set show almost constant knock retard (stock programming), up to 15-degrees. I've never notice any major side effects as described above.

speedracer2j

I had nothing hooked up, as a matter of fact the wire was just hanging there. It took me a little time to figure out what was going on. As for the tune, mine is far from stock, which is why im guessing I wasn't pulling any timing. It only showed knock on initial startup. I hope the 900mv readings go down. I was like WTF. I guess we will find out whenever SpeedInc weather gets above 40 degrees...cant wait to put down some numbers.