Hi Guys, Yesterday, I finally fired-up my engine. Cam has about 50 degrees of overlap (seat timing). Other than idle, the performance is not bad. No back-fires or hesitation when throttle is moved. During initial start-up, had to move the throttle-blade set-screw to keep engine running at an idle. Just a temp band-aid until I can figure out what is going on. Running TunerPro has a tuner platform with a WB02. Please look over the following Excel file and comment. To me, it looks like the car is lean. The exact opposite of what I expected! INT : Saw-Tooth Response BLM : Maxed NB O2 Voltage : Low WB O2 : 17:1 to 18:1 , small periods are higher. Exhaust smells clean. Headers not glowing. Maybe I have a bad (brand new) Bosch NB O2 sensor? No Trouble-Codes Set. The Excel file highlights the open-loop startup and the closed-loop idle run. Best Regards, Bruce

For some reason i am not able to open zip files posted on this site. Internet Explorer sucks i guess.

But from the symptoms, and that WB readout, your way too lean on startup. Bring in more fuel to get it closer to 14.5-15 to 1.

My car was starting up near 17-18 to 1 and i had to keep throttle up abit to keep it alive. It needs more fuel.

Low NB voltage i do believe is confirming the lean condition. So add some idle fuel

Hi Guys,

Completed some trouble-shooting today.

Set the Base-Timing to 6° BTDC. The headers started to glow when the "bypass" connector was pulled apart.

Set the Throttle Body set-screw so the Idle IAC counts were in the mid 50 range mark. Just tyring to get close during the preliminary trouble-shooting.

Injectors are Bosch-III 24 Lbs/Hour @ 39 PSI.

Based on 2 different O2 measurements (NBO2 & WBO2), the car looks fairly "lean" at idle.

Running full emissions. So the Air system will effect the WBO2 during "open" loop when the air is sent to the "port" (headers). After "closed" loop is engaged, I believe the air is routed to the CAT. Correct?

The WBO2 is installed before the CAT input. The NBO2 is installed in Edelbrock Jet-Hot coated TES headers.

These headers are about 13 years old and have been used without any problems with stock un-heated O2 sensors.

At Idle, the WB O2 indicates around a 18:1 to 19:1 AFR. After searching the boards, many guys have experienced typical idle WB02 measurements (after tuning) in the 17:1 to 18:1 range. I assume this is with cams much more radical than mine.

The problem I have is the NBO2 sensor cross-counts is very low and the nominal voltage is also low.

Please reference the attached files.

The only way that I can get the NBO2 to move (relative to very low nominal voltage) is to move the throttle. Notice that the NBO2 starts to function when I move the throttle. Also, the BLM moves closer to 128.

Comments on the data?

What is the preferred approach to change the idle fueling?

A full pressure change is not enough. Tried that method.

I understand that the MAF tables are grms/Sec vs. Volts.

What is the easiest way to figure out what MAF parameter to move?

Based on reading the threads, it looks like Table 1 is the one in question.

Best Regards,

Bruce

table 1 MAF is the right one. increase those a few gr/sec and see where that gets you.

with it going that lean, and the EST disconnected, your without alot of timing and that will cause it to run very hot and start glowing headers.

give it some timing, probly closer to 10 degree base and richen it up alot.

Thanks Orr89RocZ,

I will play with table 1.

Any way to calculate the Grms/Sec offset from the data within TunerPro?

How does a Grms/Sec offset (to get the fueling correct) effect the LV8 calculation and the Ignition side?

Best Regards,

Bruce

That I am not 100% sure off the top of my head. It was posted here along time ago and i think i have some of those threads saved. I'll have to look thru.

But I dont believe your gonna beable to calculate your correct gm/sec for a desired air fuel ratio. I just played with them until i got it where the air fuel looked good and made the motor happy. where ever you are lean or too rich than what you want to be, record the MAF grams/sec value and then go into your table to find that value or one thats close to it. Then increase it to richen, decrease to lean out. Pretty simple

Orr89RocZ,

Thank you.

Given my Cam, what type of vacuum should I measure @ 900-1000 RPM?

LSA 111

Dur = 218/224 @ 0.050"

Dur = 268/276 @ 0.006"

Lift ~ 0.570"

Overlap = 50°

Just want to make sure a vacuum leak is not causing the NBO2 to act up.

Tomorrow, I will try some MAF Table 1 tests.

Best Regards,

Bruce

at 900 rpm, that cam should read some good vacuum. I dont know an actual figure, but i dont think you'll have ANY issues with brakes It should have some high vacuum.

Talk to 1989GTATransAM and Kevin91Z. They have run similar cams on 350's and Kevin tunes them. He may beable to give you some good pointers.

Be sure you do not have a header leak near o2 or before o2, will pull in fresh air casuing 02 to read false lean.. Being that car barely ran on start-up I would assume you are actually lean.. But glowing in headers is always rich or way retarded timing, 6° is low, but does not really matter once esc is connected and prom is set correct. You probably want around 18°-20° with esc connected. Be sure to reset TPS since opening T/B. Look at IAC counts now with T/B opened, If they are way high - like 100+ open it more. I am thinking it probably is.. Its normal to require more idle air when cammed - open throttle body till IAC counts are near 20-30 in gear.. I run mine very close to 0, but not best for everyone. I just like as little influence as needed - an old trick from Grumpy (R.I.P.).. check your plugs at idle, look at color and threads - how far up threads are black, don't always trust 02.. cam should not cause issues with its size, but some here fail to understand that theer is more overlap below .050, like with gradual ramps. Had that problem with a 230/230 cam on 110, had to run open loop always, much less at .050 than current cam, 30° more at .006... Current cam is 248/254 no issues in open loop.

Thanks 87_TA,

Good point about the header leaks around or before the NBO2. I will check.

The 50° overlap is based on seat (0.006") timing.

The present idle timing at 900 RPM is around 25° BTDC.

Will check the TPS voltage.

This cam is fairly small compared to what you are running.

Been wondering about vacuum leaks?

The idle BLM approaches 158. About a 23% fueling increase over the calculated fueling. I assume the caluclations are based on mass air flow and MAT?

For many years, I ran the car with the Crane 2032 grind and a calibration that I purchased and then slightly tweaked.

For this latest cam, I have also purchased a "starter" tune and plan on finishing the tune myself.

Presently, I am looking at the difference between the MAF Table #1 calibration for the final 2032 tune and the preliminary new cam tune.

The new cam engine configuration idles at 900 rpm, 27° advance, 2 mS PW, and 8.4 grms/sec.

Here are the closest "old" and "new" MAF Table #1 numbers.

Voltage Old New Delta

0.73 8.16 7.48 -8.3 %
0.91 10.91 10.14 -7.1%

The new calibration may not reflect the vendors knowledge of the MAF modifications. Gutted screens and heat sink. The MAF is old and has run fine for many years. The old configuration reflects flow numbers that are large than stock GM.

From what I have learned, with MAF cars, there are two ways to arrive at the Base PW. By table or calculation.

Found the equation from RBob on the MAF BPW calcs.

Interesting, the MAF flow rate, desired AFR, and the Injector Flow Rate are utilized.

Not the MAT?

The bottom line is I can not see where the MAF Table #1 calibration is 20% off. At least to cover the BLM change.

Am I looking at this situation the correct way?

Is there another programmed variable that I should also compare between the old "optimized" and new "preliminary" bins?

What is the difference between the following?

Injector PW Offset vs. Battery Voltage

Injector PW Offset vs. Base PW

Not sure about the second table?

Starting to serious look a the possibility of vacuum leaks. Many possibilities!!

This is the reason why I am going to measure the idle plenum vacuum. If the vacuum is low, i plan on checking the following.

PCV System for vacuum leaks.

Throttle Boddy conections for the canister and EGR.

AFPR.

Heater / Vacuum sphere.

Fuel Injectors.

It is interesting to note that I set the AFPR to ~ 3 bar (43.5 PSI) with no vacuum. When the engine is running at idle, the puel pressure is around 39 PSI.

Conclusion is the vacuum must not be too bad. Comments?

One final note, I am running the Bosch-III (24 lbs/hr @ 39 PSI) injectors.

Thanks again for the help.

Fairly confused at this point.

Best Regards,

Bruce

I raised (richer) the first 6, maf 1 table values (arap bin), by this amount to get to 128 from 158 blm at idle.

volts grm dif
0.91 11.41 0.54
0.73 8.98 0.63
0.55 7.10 0.90
0.37 5.12 0.63
0.18 3.68 0.45
0.00 8.36 0.00

Something like this should get you close.

The O2 volts being low and the limited cross counts are going to leave you in open loop. So the open loop tune will need to be closer, or a heated sensor installed.

Hi Pandin,

Thank you for your suggestions.

I would also think the system would never go into closed loop.

However, we I look at the status flags (after warm-up), the system appears to be in closed loop.

Today, I checked over the exhaust system (from the headers to muffler) and I do not think there are any sealing issues before the NBO2 and the WBO2.

From the exhaust system perspective, the AFR data looks real.

Also, I measured the plenum vacuum at my rough tuned idle. The selected port was the AFPR vacuum fitting.

The idle plenum vacuum was around 12. Was expecting 15. However, the system is not well tuned.

Tomorrow, I will determine if any simple vacuum leak root-causes exist.

Also, I will update the MAF Table 1 per your suggestions.

It just occurred to me that my system system is running in double fire mode.

I would think that if each injector pulse is off by 10%, the cumulative fueling error would approach 20%? Therefore, small changes in the MAF tables change the AFR fairly quickly.

Yes, I may not actual have a mechanical problem after all.

Best Regards,

Bruce

how much total timing are you running at idle? Give it 24 degrees and it will help that vacuum and help stabilize the idle characteristics. Get the MAF tables to report good air fuel ratios and then reset the TB idle screw/IAC sensor to get your IAC counts below 20 at idle. I'd say give it 850rpm idle speed in the chip and then adjust the TB idle screw for that speed.

Hi Orr89RocZ,

The total timing I am running ( ~900 RPM ) is around 26 to 27 degrees.

Tomorrow, I will update the bin.

Thanks for the help.

Another update report tomorrow.

Best Regards,

Bruce

As said by others, my guess is that the modified MAF is the culprit, and as such, the MAF tables need the flow to be corrected (it's getting more air than it thinks).

INT and O2 in a sawtooth pattern means it is reaching 14.7 according to the narrowband. The BLM maxxed means the MAF tables need to be increased.

Now, how to get the wideband and closed loop to match up will be an exercise (and possibly futile).

26 degrees should be fine at 900. Thats what i ran with my big cam to smooth out the idle. 26-28 on my cam at 1000 rpm

Thanks RednGold86Z and Orr89RocZ.

Yes, I am convinced the MAF tables are wrong.

With the Old Cam (Crane 2032) the revised tables for the modified MAF worked great.

Today, I am going to put those tables back in and implement some idle logging.

Just wanted to check for a potential mechanical problem before changing (or chasing) the calibration.

Thanks and Best Regards,

Bruce

Hi Guys,

Another round of trouble-shooting is complete.

Although the data is interesting.

Bad News:

Even after changing the MAF Table 1 entries as follows:

Voltage Old grms/Sec New grms/sec

0.0 5.5 6.79
0.18 3.09 3.78
0.37 4.04 4.98
0.55 5.41 7.13
0.73 7.48 9.20
0.91 10.14 12.29
1.10 13.49 15.98
1.28 17.02 20.11
1.46 21.40 21.40

The NBO2 is still lazy. It only switches when the Throttle is moved or the engine is run at a constant 1600 RPM. However, the switching waveform looks somewhat lazy.

Please see the attached word document.

The NBO2 waveform peak to peak switch amplitude should be at least 2.5 vertical divisions.

Notice when the RPM was raised, the WBO2 indicated an AFR slightly lower than 15:1. The BLM is about 110.

Somehow, the computer was able to read the NBO2 switching and reduce the fueling.

I am really starting to wonder if I should upgrade to a "heated" NBO2?

If so, can you suggest some vendors and model numbers?

Do I require a seperate DC power relay or can I run the "Heated" NBO2 off of another relay?

Given the old cam (Crane 2032) I did not have problems with the NBO2. I wonder if the EGT was higher with that cam?

Good News:

With the increased fueling, the idle IAC counts are around 30 and the plenum idle vacuum has increased to 14 mm Hg. Not bad.

I checked the PCV system and found the idle vacuum did not change when I plugged the base-plate hose with my finger.

The AFPR vacuum port appears ok. Without any vacuum applied to the regulator, the fuel pressure is ~ 49 PSI. With the AFPR vacuum port connected to the plenum vacuum port, the fuel pressure is around 44 PSI. does the rate of change sound ok for an idle vacuum of 14 mm Hg?

Next time I run the car, I will check the Throttle body EGR vacuum port system for leaks.

At this point, i do feel the idle fueling should be increased any higher. My values are higher than the reference provided by Pandin.

Comments?

Next Steps:

I am seriously thinking about the "heated" NBO2.

Could my cam upgrade from the Crane 2032 cause the EGT at idle to fall to the point where the NBO2 is just not hot enough?

Maybe I have a bad brand new NBO2? It is a Bosch unit.

Further suggestions are greatly appreciated.

Best Regards,

Bruce

Hi Guys,

Additional thoughts for my post yesterday.

1.
I am still confused how the ECM can go into Closed-Loop when the NB02 sensor switch counts are so low?

Maybe RBob can shed some light?

I can see closed loop effects in the WBO2 indicated AFR. When Closed-Loop starts, the WBO2 indicated AFR decreases.

2.
Let's assume the indicated WBO2 is 17:1. The 50 degrees of overlap (cam seat timing) is fooling the WBO2.

What is the NBO2 AFR dynamic range? Maybe 13:1 to 15:1?

I would think the NBO2 would be fooled just like the WBO2.

Since the AFR dynamic range is not high, a lean (low voltage) condition would be indicated?

If the above is true, I would increase the MAF Table 1 until the WBO2 would indicate a 14.7:1 AFR.

Am I correct in assuming the car would smell very rich and the NBO2 would switch properly?

There are many examples of much bigger cams then mine running fine. The CC503 is an example.

The Cam valve events are as follows:

CC503

IVO = 30.0° BTDC
IVC = 66.0° ABDC
EVO = 76.5° BBDC
EVC = 24.5° ATDC

Overlap = IVO + EVC = 54.5° (seat timing).

My Custom Cam (modified CC 268XFI : LSA = 111°)

IVO = 27.0° BDTC
IVC = 61.0° ABDC
EVO = 73.0° BBDC
EVC = 23.0° ATDC

Overlap = IVO + EVC = 50.0° (seat timing).

A couple of points are worth noting.

• My cam has much less overlap. However the lift is significantly higher.
• My IVC is earlier. Less MAF reversion than the CC503.
• My EVO is later. Better low-RPM cylinder pressure.

Would it be possible for someone running a CC503 to comment on my tuning issue? The cams are similar.

For those with bigger cams, what maximum WBO2 indicated AFR was noted when the NBO2 started to switch normally?

3.
How can I detect a cold NBO2?

Does the response look lazy (very slow) and lean?

Since I can see the O2 bias voltage of 0.45 Vdc, I believe the system wiring is ok.

4.
The only way that I have found to get the NBO2 to switch is to either quickly increase the throttle or increase the steady-state RPM.

Usually, the throttle jab works every time.

The steady state RPM increase works if the RPM is high enough.

Check out the attached (Trouble_Shooting_2_090321.doc) performance chart.

This chart highlights steady-state idle, RPM increase, and ends by going back to steady-state idle.

The MAF Table 1 was set-up as I indicated in the prior post.

Steady-State Idle, the parameters are as follows:

RPM = ~ 1000
BLM = 138
WBO2 AFR = ~ 17:1
NBO2 Voltage = ~ 31 mV

During steady-state 1500 RPM.

RPM = ~ 1500
BLM = 108
WBO2 AFR = ~ 12.5:1 to 15.0:1
NBO2 Voltage = ~ 0.9 early to actual switching

The final idle parameters

RPM = ~ 850
BLM = 138
WBO2 AFR = approaching 17:1
NBO2 Voltage = approaching 30 mV

Did the NBO2 start functioning as a result of the AFR change or higher EGT or both?

Another example of the above test process.

This time, the NBO2 did not function well.

Please reference the “Trouble_Shooting_3_090321.doc”.

Each vertical division within the LC-1 WBO2 graph represents in increase in the WBO2 reading of 2.5:1.

Check out the area where the WBO2 indicated an approximate 15:1 AFR. The narrow band O2 voltage hardly moved.

Also, the BLM decreased from 138 to roughly 128.

Given the lousy NBO2 voltage, how could the BLM move without the proper O2 feedback.

The NBO2 sensor does not appear to be switching?

How can the NBO2 give up so close to the 14.7:1 goal?

5.
Within the TunerPro ALDL Data-Stream definition, the NBO2 is set-up as follows:

ECM : 165 ($32B)

Byte = 17

Operation = Multiply[(X*factor)+Offset]

Factor = 4.40

Offset = 0

Is the above setup correct?

6.
The main issue that I noticed is the NBO2 gives-up for indicated WBO2 AFR values greater than 15:1.

Is this normal?

The NBO2 just flat-lines.

Keep in mind that I am running a Bosch NBO2.

It seems like this is the only vendor that most auto-stores carry in my area.

7.
How would a heated NBO2 perform differently?

The bottom line is how can I differentiate between the AFR dynamic range and an EGT issue?

The RPM increase in the above tests should have prevented the cam overlap from corrupting the indicated WBO2.

What other experiments can I try?

No sure if I should increase the MAF tables any further? The MAF tables ran just fine with the 2032 cam.

Best Regards,

Bruce

I would start with put in a heated NBO2

/N.

Thanks GTA324.

I am leaning the direction of a heated NBO2.

What has been your experience with the idle NBO2 performance vs. the WBO2 AFR?

Many on the board have indicated that a 17:1 to 18:1 idle AFR may be normal with a cam that exhibits 50° of overlap.

Best Regards,

Bruce

On all cars I have tuned I have recommeded a Heated O2,

I do all my tuning on my car according to WBO2 (open loop) and EGT.

some reading

http://www.thirdgen.org/techboard/di...m-results.html (Idle tuning with cam, results.)

http://www.thirdgen.org/techboard/di...t-mixture.html (Best way to adjust Mixture)

Gotta take the dog for a walk now.......

/N:

For heated NB o2 sensors:
Delco, AFS-73 is the three wire
A= Heater Power (Red)
B= Heater ground (Red)
C= Signal Output (White)

This uses the exhaust parts to make the ground for the signal.
I run one of these and have not had any issues with that.

Delco AFS-74 is the four wire version from LT-1 apps.
A= Signal Ground (Tan)
B= Signal Output (Purple)
C= Heater Ground (Black)
D=Heater Power (Pink)
This unit has a wired ground to eliminate the possibility of signal ground problems.

The letters designate the weatherpak connector IDs that are molded into them. Colors arethe std but may be different, just a reference.
Jp

Edit: I might have my numbers incorrect.
I'm thinking the 74 = 3 wire and 75 is the 4 wire. My notes from when I bought them are not clear anymore.
Double check me on that.

Thanks JP86SS and GTA324,

Still attempting to wrap my head around the 6" vertical stack of posts from this Website!.

Regarding the AFS-74 and AFS-75 heated NBO2 sensors, what is the best way to obtain the mating weatherpack connector?

I am going to install one of these heated devices. I read on this board that the AFR-47 may have a slightly slower switching response when compared to the AFS-75. Which one would be better to integrate with my 165 ECM?

I looked over the NBO2 transfer function (Voltage vs. AFR). It looks like the NBO2 sensor is not very useful above a 15:1 AFR. This is very similar to the data I have posted. How does EGT effect this curve? Does EGT shift the curve to the right or left?

What is the advantage of the heated NBO2 over the single wire NBO2? Less sensitivity to EGT?

Regarding tuning techniques,,,,,,,,

From reading the posts on this board, it seems like the false lean O2 readings that result from Cam overlap is a real effect. The intake charge O2 fools the O2 sensors into measuring a high AFR than really exists in the combustion chamber.

Given this effect, why would we adjust the MAF Tables to achieve a 128 BLM at idle?

Why not run the RPM at 500 RPM or greater above the idle speed to implement a rough check on the MAF Table 1 transfer function? Maybe check a few RPM points? the goal would be to see if we are in the ballpark. If the slightly higher RPM BLM performance is in the ballpark, would it be a good idea to play with the idle O2 constants at this point? As opposed to increasing the MAF Table 1 idle values?

My existing MAF transfer function worked great with my old engine combination. Other than intake reversion, I am not sure why I would need to update the MAF tables?

Just wondering if I am being fooled by the idle BLM correction and the indicated WBO2 readings?

Thanks again for the help.

The funny thing is the car seems to idle great. The engine responds well to throttle input. No lean pops or idle troubles after a throttle pulse.

Also, I can not detect any surge at idle.

Thanks again for the help.

Best Regards,

Bruce

What are the plugs showing at idle?

Tperature can shift the output of the o2 sensor but I don't know the direction or magnitude.
The only ill effect I know from running a single wire o2 is that during idle it can cool down and put you back into open loop. Once you get going and it heats back up you'll go back to closed loop. The actual readings between the two when warmed up are the same (technically)
Each has thier own little quirks as I understand.

One of the big challenges trying to tune the GM TPI is the relationship between the Maf vs true air flow, Injector flow vs injector constant, and the NB/WB output vs AFR.

None of the "variables" are "perfect".

They are only a "best guess" and you have to pick something to anchor your tune to.

The most accepted is, in Closed loop and at a steady cruise speed, use the BLM (128) as the anchor. Adjust the injector constant to match the injector flow. Then adjust the Maf/VE tables to bring the BLM to 128. This is not the only successful way to tune but is what quite a few TGO people have used.

The issue is you have 4 different items and not all of them, when set to a "proper amount", will give 4 acceptable numbers.

I have found, with my set up, is each is a compromise. If the afr/ BLM is at 128 then either the Maf or the injector constant is way off. And the NB/WB don't always read the same. AFR 14.7 and 128 BLM are not always together with each other.

This inconsistency really makes tuning a big challenge, because I never really know which "number" is "correct" and which is "fudged".

BWilcox

If your steady speed 1500 rpm BLM is at 108 then you are at the limit of what the ECM can adjust for and will need to adjust the injector constant and/or Maf table to level the difference from Idle to cruise.

I shoot for a 14.7 AFR/128 BLM at 55 mph, then move the Lower maf tables for a good idle rpm. The idle may or maynot be 14.7 AFR.

Thanks Pandin,

The posts on this board are really good.

Requires a fair amount of time to put all of the information together.

Thanks to you and the other guys for helping me.

Your tuning experience / process steps really helped me out.

I will send another update soon.

As soon as I get the idle worked out, I will drive the car around the block.

Nice and easy. Then process the datalog.

Thanks again,

Bruce

Hi Guys,

I purchased an AFS-75 NBO2 sensor and the associated pig-tail connector.

I plan on soldering the wires. Some time ago I saw a post from Grumpy on the effects of soldered vs. crimped wires.

Suggestions?

Best Regards,

Bruce

IMO,crimp them and then solder too.
After fully remaking my engine harness from scratch with that method I have had zero electrical issues. Including not having the grounding offset problem during cranking that many LC-1 users have observed.
I just don't like worrying that something wasn't done right when I had all the time in the world to be sure that it was.

Ps, can you post the wiring connections and color of the AFS-75.
I don't have any info on that one.
TIA

For the average guy making harness modifications, soldering + heat shrink is probably the reliable solution vs cost and effort. For OEM, NASA and F1, a calibrated crimp is best. Soldiering tends to make joints somewhat brittle (weeps up under the insulation and also damages the insulation), or is "cold", or full of slag, and can't always stand up to 100k+ miles, and is time consuming. A crimp, if done right, can stand up to much more abuse. If done wrong, a crimp will either fall apart, corrode, or be too tight and cause the wires to fail. A pos crimp tool and plastic butt connectors are a definite no-no.

One thing I see on our O2 sensor wires is that they're high temp, stiff, and can't take solder very well. Also, for the sensor, the backside of the O2 sensor needs O2 as a reference, and the source of O2 is usually through the wire - weird but usually true (I do know of some of our sensors with a membrane opening, like "Gortex" or whatever that was called, and then the wires aren't needed as a source).

Just some info to consider. I almost always solder - sure beats twisting and taping!

i don't recommend soldering the wiring on the O2 sensor side of the O2 connector for the reasons given. i've not had any problems soldering the car side of the O2 connector.

when im repairing a harness, i look at where the repair has to be done at. how many wires have to be repaired, and how much room i have to work with. also, if its some place that the harness will see very much vibration or
movement, i use bare crimp connectors with 1 wrap of tape and top it off with heat shrink tubing.
if the harness is in a place where it isn't going to see movement or vibration, i will either crimp & solder, or twist and solder, then a wrap of tape and finish with heat shrink tubing.
then i tape the harness back up and put wire armor on it.
if its a heavy power or ground, i crimp and solder. when i tape that part of the harness back up, i reinforce the area by cutting the lock end off a couple of tie wraps and tape the tie wraps into the harness.
it doesn't matter if im crimping or soldering, i always clean the bare wiring with a red scotch brite pad.
before the first wrap of tape goes on, check for and fix any sharp points.
under the hood or body, i use self sealing heat shrink tubing.
under the dash i use regular heat shrink tubing.
also, always stagger out the repair joints when ever possible.


JP, i believe the ASF-75 is for 96 & up vortecs and some other later model GM vehicles, so i think this what your looking for.

Thanks Guys,

Yes, my soldering would be on the "car" side of the NBO2 connector.

Thanks for the information on soldering vs. crimping. My professional background is on the soldering side. Never thought about the ability of the solder to stand up to mechanical stress.

I am planning on obtaining power from the ESC feed. How much power does the heater require? Maybe 18 Watts? The goal is to place a heater fuse between the ESC power feed and the O2 Heater.

Given a "cold" non heated NBO2 sensor, I would think the output voltage would be low (lean). Correct?

Thanks Guys,

Bruce

Here's a GM 4-wire O2 sensor wiring diagram if you prefer a lower-tech version than the one posted earlier.

Thanks Guys,

Over the last couple of days, I managed to datalog.

Interesting results.

1.
Given the MAF Tables and Scalers that were set-up with the 2032 cam, the cruzing BLM were 128 +/- 8. Not bad for a start.

2.
The LC-1 WBO2 sensor 14.7:1 seems to correlate well when the BLM is at 128 or the integer is stable at a non 128 BLM value.

3.
The car drives great during part throttle and off idle.

4.
So far (no PE work yet), the only problem is at the 900 RPM idle.

The OBO2 voltage is around 45 mV to 50 mV. The WBO2 AFR is around 17:1.

The idle is fine. A fair amount of lope (sounds good) but very well behaved.

Of couse, the idle BLM can be high, depending on how I set the Maf Table 1.

5.
For you guys with bigger cams, what is your idle NBO2 voltage?

Presently, I would have to add way too much fuel to bring down the BLM.

6.
I have not experienced any "lean" type idle effects. ie. off idle hesitation or intake pops.

Confused??

Best Regards,

Bruce