Bonneville and massive error

[Karpov]

you have a scantool that pulls o2 volts so diagnose the sensor - not that hard, then check injectors

O2 sensor shows 400-700mv. Not stable.

[96 SSEi]

the front, pre cat is supposed to fluctuate from very low to high - my 2000 is from .03 to .75 - if it stays steady within a range then it is slow or going bad. the post cat sensor stays in a range around .450

[95naSTA]

Post cat O2 sensors didn't exist until OBD2 96+

I'm not sure what the stock mv reading should be for the O2s or how fast it should oscillate.

[Karpov]

Your opinions about videos? (Aijaa.com links)

Tps adjust did tcc to work smoother!

I must order new 02 and injector o rings.

But can faulty 02 do heavy cutting on engine at higher rpm?

[95naSTA]

Which videos?

If the O2 sensors are worn/old it won't be able to adjust the fueling correctly, causing a drop in gas mileage.

[Karpov]

Which videos?

If the O2 sensors are worn/old it won't be able to adjust the fueling correctly, causing a drop in gas mileage.

Now i have video what car does in acceleration and idle. I have aldl connected on idle when car sputters.

https://aijaa.com/AlMOQK idle poor running with tuner pro on

https://aijaa.com/hOUFp1 sputtering was mild. Its usually worser

When you open link, there is video

[95naSTA]

I would not revving the engine with no load that high in idle or park. It's really lean up there BLM of 150+ but I would expect that since there's no load.

The driving video showing the shift seems like the transmission slips or the engine hits a limiter at the top of the shift.

[Karpov]

I would not revving the engine with no load that high in idle or park. It's really lean up there BLM of 150+ but I would expect that since there's no load.

The driving video showing the shift seems like the transmission slips or the engine hits a limiter at the top of the shift.

In drive its usually same that park. Rev limiter is just after 5000rpm and its smooth. Not in 4000rpm. It seems like slip but engine surges and then rpm drops.

I know its not healthy to rev in park, but there is some problem its not that kind when its working correctly.

In carb engines lean mixture pops and bangs in heavy throttle. So if you see lean mixture on that rev video it can be the problem.


But what makes engine lean on high rpm?
Fuel filter is good and new like fuel pump. And fuel pump gives healthy pressure.

[95naSTA]

The only thing I can think of is the O2 sensors then.

[Karpov]

Now i have new delphi o2 sensor and i cleaned injectors.

Now o2 volts are 90-900mv in idle. Afr was 13.7 until i pressed gas.

Block learn multiplier was 105 and fine fuel correction 135.

[Karpov]

Today measuring and testing. Now car is open loop all the time even its warm. Restart didnt effected or just ecm fuse reset.


What can cause that? No fault codes

[95naSTA]

I'm having a rough time with this one.

Low coolant temp and an unplugged O2 sensor can keep the car from going into open loop but I'm not sure what else.

[Karpov]

Temp sensor is pretty new and it shows like it should.

New o2 sensor has been in now about 100miles.


Every day when i look thru my homes window and see bonneville in parking slot, i wonder what so bad i have been done that american engineers punish me like this :D

[Karpov]

I tried to take fuel regulator hose off which richened idle etc. Blm was 105-110 and fine fuel same.

Why fine fuel correction wont try fix it 128 or why stock adjust is all the time rich (only 4000rpm it was lean)

[95naSTA]

If you were in closed loop, the BLM being low with the vacuum reference off makes sense. Vacuum helps open the regulator to return the fuel and give lower fuel pressure.

You have a base fuel map the the BLM tells the ECU how much more or less fuel to deliver from that base map. The INT is the short term memory and it's trend changes the BLM. The closer you are to 128, the less your ECU is compensating and generally should run better.

From what I understand, if the ECU is in open loop, the INT never tells the BLM how much to adjust.

[Karpov]

In normal situation i had 120-110 values both. Vacuum of it dropped, it was just test.

It has not been in open loop befote ar warn engine, now it is


So many things are wrong :(


What all causes and things effect blm and int? Sensors etc

[95naSTA]

The only thing that impacts the BLM and INT is the O2 sensor input.

[Karpov]

Maf does not effect?

[95naSTA]

Think about it as a feedback loop. Initially, fuel is determined by LV8 (load) and rpm. Load is determined by MAF, air temp, etc. The O2 sensor sees whether or not the fueling is correct, assigns an INT number (short term memory), trends the BLM (long term memory) and then fueling is adjusted from the base map accordingly.

The MAF doesn't have a direct influence on the INT/BLM. Only after the O2 sees how much oxygen is in the exhaust, does the INT and BLM change.

[Karpov]

New o2 sensor is coming to me. I just wont believe that new o2 sensor fixes my problem


This car's engine management system is mess and im very much out for that :(


I dont understand why its open loop in hot engine and aometimes not. I understand if there is some "2minutes aster start closed loop if engine is hot" but it wont do it even 30minutes on driving, if its bad day.