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Old 11-20-2019   #1
We Gone
 
Join Date: Apr 2004
Location: ATL. GA.
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Default BLM/INT ?

So I'm helping a buddy with his 92.I'm thinking new O2s ?

BLM & INT are low on left bank at operating temp.

BLM L 99, R 132

INT L 100 R 139
Cross-counts are good
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Old 11-20-2019   #2
oldpro
 
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Default Re: BLM/INT ?

Wow very rich on left side you could switch o 2 s and ck the results before buying a new O 2
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Old 11-20-2019   #3
We Gone
 
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Default Re: BLM/INT ?

So could be a bad or leaking injector?
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Old 11-20-2019   #4
oldpro
 
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Default Re: BLM/INT ?

To ck for s leaky injector put s fuel pressure gauge on the shreader valve at the end of the passenger side fuel rail . Turn on ignition then turn off and see if the pressure holds if you loose pressure right away then you could have a leaky injector
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Old 11-21-2019   #5
We Gone
 
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Default Re: BLM/INT ?

Thanks my though also, I now what the readings should look like, did not know what it was showing as far as rich or lean on the left bank.
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1990 Steel Blue/Black #2355
1990 Red/Red #1473
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Old 11-21-2019   #6
XfireZ51
 
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Default Re: BLM/INT ?

Quote:
Originally Posted by We Gone View Post
So I'm helping a buddy with his 92.I'm thinking new O2s ?

BLM & INT are low on left bank at operating temp.

BLM L 99, R 132

INT L 100 R 139
Cross-counts are good
Have u checked for any exhaust leaks on the Left side?
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Old 11-21-2019   #7
We Gone
 
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Default Re: BLM/INT ?

No have not, When driving it had a slight roughness when the secondary's opened but cleared up after 5500rpms.
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Old 11-22-2019   #8
Paul Workman
 
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Default Re: BLM/INT ?

Well I see the gang has nailed all the "low hanging fruit". One thing tho, can you get an average voltage readout for the O2s? 400 to 500mV is good. 700s and up indicate rich and 300 and less indicates lean.

Assuming the O2s are verified to be in good operating order, (and generally speaking) IF a BLM reads rich, I'd be thinking of leaking injector(s), maybe. But, if lean, I'd be thinking of measuring the resistance of the individual injectors when they are HOT.

Swapping O2 position is where I'd want to start - see if the errant readings follow the O2.
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Old 11-22-2019   #9
We Gone
 
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Default Re: BLM/INT ?

Thanks Paul,

may be a few weeks before I get back to his house, I do have 2 good O2s I changed out of mine years ago when I had Marc do the upgrade package I'll try one of them on the left.

As to voltage readout both range (Stock car) from the high 90s to just over 700 constantly cross counting. On my car I get reading from 80s to 800 but its not stock.
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1990 Steel Blue/Black #2355
1990 Red/Red #1473
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1993 Yellow/White #179 Sold
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Old 11-24-2019   #10
Hib Halverson
 
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Default Re: BLM/INT ?

With block learn and integrator low, the system is obviously pretty rich and, thus, pulling a lot of fuel. That in conjunction with "cross-counts are good" has me thinking an injector problem rather than an O2S problem.

Run the fuel pressure tests in the Service Manual. If those tests pass, then swap the O2Ses. If the problem moves to the other bank, then I'd replace both O2Ses.

If the problem stays on that side, I'd pull the injectors and send them to someone like RC Engineering for cleaning and testing.
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