urbaNHunter44

I just finished an HCI swap in my LT1 car. LE2 heads, ported intake, 32lb injectors, 22x/23x, .6xx/.6xx, 10x camshaft.

It gives me alot of low RPM sputtering (no misfire counts on the scanner) and the driver's side plugs are black, #7 is actually wet with gas.

I keep getting DTC codes P0134 and P0154. The bank 1 code always sets before bank 2 and it's always within a minute of starting the car. At idle (open loop) both sensors are pulling 350ish mV, under load (cruising, 20% load) bank 1 is around 400-450 mV, bank 2 is 10-200 mV. I'm also getting 4 degrees of KR at 20% load.

Could the cam swap have killed the O2s this quickly? I'm going to swap the O2 sensors but I'm afraid it's just going to kill the new ones.

The car has a PCMforless tune on it. Is this something that could be fixed with just tuning or is it another issue?

I did find that my EVAP system wasn't hooked up properly so I hooked it back up, but I doubt that could cause a problem. The car has an EGR valve on it but it is not hooked up to a vacuum source.

Any ideas?

2QUIK6

Were the injectors also swapped at the same time? Not clear from your post above but it sounds like multiple things were done at once.
Was the PCMforless tune for those injectors?
Whats the LT integrators/BLMs at idle and 30 mph cruise? (I take you have a scan tool since quoting the O2 mv, which aren't much help if the BLMs are way off of 128.

Yes, running real rich can kill O2s very quickly, especially if they already had quit a few miles on them already.

urbaNHunter44

Yeah the injectors were swapped at the same time, they're 30lb SVO red tops. The PCMforless tune did include the injectors.

I'll get those numbers tommorow morning when I can drive the car. It's pretty damn loud, don't want to wake everyone up tonight Yeah I've got a snap on scanner, damn useful.

The o2s were the stockers, 70k exactly on them. I did have to solder extension wires onto them for the LT headers.

thanks

2QUIK6

Make sure the solder job on the extensions are covered very well and the connections are dam good and not too messy, the more solder the more resistance is introduced making the readings skewed. If your Long Term Integrators/BLMs are buried one way or the other, say 108 or greater than 140..I forget what the upper limit is, I'd start to look at the connections....but you still can't rule out the tune in the PCM being off.

You can put in new AC Delco O2s only, don't use Bosch, and if the reading are still way skewed, cut the car off and put the old ones back in until you can figure out the cause of the LTI/BLMs being off because you don't want to ruin 2 brand new o2s.

Also, if you still have cats on the car, you don't want to drive it too much like this either as you can burn the cat up running rich too.

urbaNHunter44

Honestly I don't think my solder job was too good, I'll pull them all back apart and redo it properly. Maybe I'll just buy some extensions if they aren't too much.

No cats, just open headers.

I'll get those numbers tomorrow, tempting to go start it tonight lol.

WS6T3RROR

Open headers can screw up your blms to with reversion from overlap on the cam. it'll read atmospheric o2 and think its lean and set both your blms to 108, = wet trashed plugs in no time. Also if your headers are new i'd heat cycle them a few times before you put new sensors in cause the fumes from a coated header will make o2's react sluggish and set a code.

urbaNHunter44

oh really, i didnt know that. if i put extensions on them will that fix that issue?

WS6T3RROR

It should, really it depends on how good your tune is and if all your sensors are reading correctly. Also in my experience, soldering extensions onto your o2 harness is hit or miss. A good indicator of if your o2's are screwed or not is to just turn the key to the on position after its all cooled down, and let it sit until the sensor gets heated properly should be somewhere around 440-450ish range. You shouldnt have to remove them from the headers to do that with the way you have it sitting now with no exhaust on it. The only other thing that can happen is a sensor becomes sluggish and will skew the blms due to time spend in rich/ lean ranges.

2QUIK6

Yeah, I was wondering how close the O2 was to the end of the header collector. Mine were about 5 or so inches back and didn't seem to effect them. Either go ahead and finish up the exhaust so its not open headers or add about a 1 foot extension pipe on each.
O2 wiring extension are about $25 each from Caspers.
http://www.casperselectronics.com/mm5/merchant.mvc?
Not sure which ones, mine came with my headers. I'm sure if you call up John at Caspers he can tell you, great folks to deal with.

urbaNHunter44

Okay, I couldn't find a reading for BLMs in my scan tool.

Key on, no start:

B1S1 - 340ish mV
B2S1 - 415-440 and dropping

Start Idle:
B1S1 - 400ish mV
B2S1 - 430ish mV

LTs at 30 mph:
B1 - 25
B2 - 5

When the low RPM sputtering started it didn't log any misfires but did give me some interesting readings. ONLY when it sputtered, the injector pulse width rose alot on bank 1.

Idle (sputtering):

B1 INJ PW: 4.0ish ms
B2 INJ PW: 2.9ish ms

On the gas (cruising, sputtering):

B1 INJ PW: 10-12 ms
B2 INJ PW: 4ish ms

I'm guessing that is my problem? Question is if the faulty o2 caused it or if it just needs a tune..

2QUIK6

The o2 numbers by themselves don't tell me much as they maye be all over the place, LT integrator/BLM gives you a good idea as thats basically an "averaged" reading as the O2 mv will be bouncing over and under the lamda 14.7 afr.
In order to test your wiring/soldering, try the test above that WS6T3RROR mentions with the car off, cold, and turn key to the "on" position but so not start the car and after the O2 get hot (because they are heated, not because the engine is on) then see what the mv reading is.

What is the LTs at 30mph above?? 25 and 5 would not be a BLM/Long Term Integrator reading, they would be somewhere between 108 - 14x with 128 being perfect afr.

Let me look at a few scans and see what my O2 mv readings are at idle and such...its been so long since I've looked at them since I use a wbo2 for tuning I've forgotten, not to mention every car I have, the o2 reading is a little different range for each...

WS6T3RROR

Perhaps his scanner shows the lterms in percent rather than counts, although 25% is off in left field and would be a blm of 160 which is possible i suppose but its the max. 02 millivolts till tell you jack about how the car is functioning they fluctuate WAY WAY too fast even to catch all of them with a logger at 10 records a second although you can see some of the sinusoidal wave.

Are these readings with the extension on the headers or no? I'm guessing no. Also what are your iac counts.

urbaNHunter44

YES, my bad, those are LT percentages!

No header extensions.

Kevin Blown 95 TA

I think one of those wires is stainless or something cause when I soldered one of mine back when I first did headers, there was one wire I couldn't solder. I had to crimp it. Also the sensors get an oxygen reference thru the jacket of the wire, so it's possible to mess that up depending on how you did it. Better to just extend the main harness, not the sensor wires. Or get the extensions.

WS6T3RROR

Yeah one of the wires is stainless. Also you have your answer for why your plugs are pure black the computer thinks its running lean from the extra oxygen and giving it 25% more fuel than it needs on one side. That can be for a whole laundry list of reasons but first things first get those extensions on there, read your iac counts and report back. Also pull your pcm batt fuse from the block in the end of the dash for a minute or two to clear the crazy fuel trims you racked up while the o2's were malfunctioning, and the car should come around a lot quicker.