Smog problem

[Bill]

Having trouble passing California smog. I think I have made significant progress, but have questions about some parameters. Have any idea what these mean?

O2 Crscnts L & R

Intgrater L & R

Requested idle is 650 RPM
Actual idle 800 RPM
IAC is 0

I'm using an Arotron CP9145 scanner

Thanks for any help
Bill

[scottfab]

Having trouble passing California smog. I think I have made significant progress, but have questions about some parameters. Have any idea what these mean?

O2 Crscnts L & R

Intgrater L & R

Requested idle is 650 RPM
Actual idle 800 RPM
IAC is 0

I'm using an Arotron CP9145 scanner

Thanks for any help
Bill

Does the scanner indicate you're running in "open loop"?

[Bill]

Negative Scott shows closed loop, engine idling for about 20 minutes. no codes indicated.

[tccrab]

Bill:

BennieC is still around over by you although he closed his smog shop a couple years ago.
I can dig up a phone number if you need it.

What are the smog nazis' giving you grief on?

TomC
'Crabs

[scottfab]

Bill:

BennieC is still around over by you although he closed his smog shop a couple years ago.
I can dig up a phone number if you need it.

What are the smog nazis' giving you grief on?

TomC
'Crabs

Because the IAC is 0 I'd say you have air leaking in somewhere.
Start with the throttle plates. Take the bellow off and see if you can pres them shut more.
What is the failure slip say? Too high of an idle or HCs to high or CO2 or?

[scottfab]

I'm using an Arotron CP9145 scanner


I think this is suppose to be
actron cp9145
right?

[Bill]

A number would be great Tom. Been fighting this for almost a year. the current problem is NO2 last test was 770 ppm and spec has been lowered to 541. I cleaned up a pretty severe vacuum leak and things look much better. I just hate throwing away $50 to fail again

[Bill]

I think this is suppose to be
actron cp9145
right?

OK My eyes aren't as good as they used to be. Problem is low speed NO2

[scottfab]

A number would be great Tom. Been fighting this for almost a year. the current problem is NO2 last test was 770 ppm and spec has been lowered to 541. I cleaned up a pretty severe vacuum leak and things look much better. I just hate throwing away $50 to fail again

With NO2 high could be the EGR is not opening. With it not opening the burn temps will be too high creating more NO2. You could force open the ERG to see.
Problem of course is you need a sniffer to tell you when you've got it.
That will be shop time.

[ittlfly]

[QUOTE=Bill;89267]Having trouble passing California smog. I think I have made significant progress, but have questions about some parameters. Have any idea what these mean?

O2 Crscnts L & R

Intgrater L & R

Requested idle is 650 RPM
Actual idle 800 RPM
IAC is 0

I'm using an Arotron CP9145 scanner

Thanks for any help

O2 cross counts is showing the O2 passingabove or below 450mv. It is sensing the exhaust gases and either adding or removing fuel depending which side of the 450 its' on. The L-R intergrator is the fuel trim the PCM is adjusting for in the short term. 128 is the center mark for the intergrater for an ideal 14:1 A/F ratio. The PCM will use the intergrator to make adjustments to the BLM's or log term fuel trim IF the intergrator is scewed constantly to one side of the 128 mark.

[Bill]

Good thought Scott, unfortunately the '90 does not have EGR, so no joy. any other thoughts?

Thats good info ittlfly It sounds like what I'm seeing is close to normal. The cross counts are constantly changing and intergrator (both l&r) varies between 120 and 130

[FULLPWR]

Hi, I just wanted to share some info of what i had happen to me just recently with trying to pass emissions here in tx.

when mine failed:
I had a bad coil, bad sec vac leak, fouled plugs, and tried to pass my
(i didnt know all that was bad when i desired a sticker badly)
the report readings were:
HC (ppm) 334 low speed 403 high speed
CO (%) .51 low speed .56 hi
O2 (%) 1.1 lo 1.2 hi
Nox (ppm) 1239 lo 1726 hi


when it passed after i found out both my cats were hollow empty
i put it new cats then readings were:

HC (ppm) 67 low speed 80 hi speed
CO (%) 0.03 lo 0.03 hi
O2 (%) .30 lo .3 hi
Nox (ppm) 6 lo 13 hi


Luis

oh, when it passed it passed with new cats and it was also before i fix the bad stuff.....go figure huh.

[Bill]

Thanks Louis,
Thats good, passing with all that bad stuff. I think my major problem was a vacuum leak where the PCV line go into the throttle block. I've fixed that and I hope all else is well. Enjoy driving your beast!

[ittlfly]

you might check your readings on your long term fuel trims (BLM"S) on both banks to be sure they aren't to far scewed on either side of 128. You should be checking at low RPM (idle) in cell 16 if your scanner shows your cell #'s. One bank that is 'out of wack'' will at least point you in direction. If you have an exhaust leak (lean condition), I would suspect that the BLM(s) will be headed way north of 128 and would be locked in. The fact that the PCM is not throwing a code shows that it is in control and the need to fatten up A/F is within the abilty of the PCM.

[scottfab]

Thats good info ittlfly It sounds like what I'm seeing is close to normal. The cross counts are constantly changing and intergrator (both l&r) varies between 120 and 130

The O2 sensors sometimes fail in a way where they swing back and forth faster than normal. (about 2x faster)
However when mine did this it caused a rich condition and hi HC only.
Do they put the sensor in both exhaust pipes?
If your lean and getting hi NX then you should see some sort of asymmetry on L or R with Block/Integrator values.
One trick I have heard of is unplugging the battery just before going in.
When in learn mode the car runs richer than normal which should get lower NX.
Keep us posted.
Could be you have some thing not seen before.
Are the HC reading ok?

[Bill]

I should have posted this in the first place

15 mph - 1504 RPM - HC-max 77--meas 44 - CO-max .5 --meas .03 -NO max 540 -- meas 752

25 mph - 1788 RPM - HC-max 59--meas 52 - CO- max .59--meas .09 -NO max 498 -- meas 345

Since then I have corrected a significant vacuum leak Idle has dropped from 1400 to 800 RPM