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dumb question about O2 sensor

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Old Jun 2, 2006 | 05:36 PM
  #11  
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Injectors: the injectors aren't leaking a drop.

The fuel didn't stain the paper.


Is the fuel rail pressure adjustable? Do you think the low rail pressure, and pressure leakdown are causing the alarms?

Blue

 
Old Jun 3, 2006 | 11:35 AM
  #12  
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Today I pulled out all the fuel injectors and did the spray pattern test.
They look and work well.

Blue
 
Old Jun 3, 2006 | 04:29 PM
  #13  
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Today I replaced the fuel filter, and an emmision control device called fuel valve.

The pressure increased up to the minimum tolerance of 54 lbs! In IS in.

I'll see how that works, but I typically like to see readings in the middle of a tolerance. If the money-light gives me any guff, I'll replace the fuel pump.

Blue






 
Old Jun 4, 2006 | 04:34 PM
  #14  
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88Silver560Sl,

Thanks to your help, I found the problem. When I replaced that fuel valve, the whole situation cleared-up, the alarms cleared, and I got my emmisions to pass.

FI has always been my downfall. Regardless of the computers and alarms, I always end up bench testing every single component, and when little mysterious emmisions gadgets break, I pull my hair out. Most/all of my factory experience is with manufacturing and machining blocks and assemblies, so if I can ever help you in that area, you will have my full attention.

Thanks for helping me.

Charles

 
Old Jun 10, 2006 | 10:11 AM
  #15  
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OH NO. The stupid light came back on.

Well, I did only have the minimum fuel pressure to barely eek by.

Any other suggestions? I'm still thinking "fuel pump". I took the intake hose to the fuel pump and stuck it into a bottle of gas and still only got 54lbs. So I don't think any screens are clogged.

CJ
 
Old Jun 12, 2006 | 10:01 PM
  #16  
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Default RE: dumb question about O2 sensor

is the engine running smooth?. look for a vacuun leak, this will make the car run lean, and trigger a fuel code. it does not mean you have a rich system wich is too much fuel and normal amount of air, but it could be lean system wich means the right amount of fuel but too much air caused by a vacuun leak.also if the fuel pressure regulator is vacuun actuated, check the vacuun hose for craks,this will make the car run rich in fuel since it needs the vacuun to bring the pressure down a few lbs at idle.
 
Old Jun 13, 2006 | 03:18 PM
  #17  
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Wow, this has really turned into a mouse-hunt.lol
But I'm getting a mechanical tour of my car, which is good because shes getting older.

No, the engine is running smooth, otherwise with no problems at all, which makes it tough.
Good idea about the intakes and hoses!
I know the injector seals are good already. LOL

C
 
Old Jun 15, 2006 | 10:12 AM
  #18  
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OK, for the record, in case anybody's following this.

Got out the vacuum tester lastnight and tested the EGR valve, working well.
Checked the controls on the crankcase ventilation system, all working.

WOW, the intake-duct to intake-manifold seal sure looks beat, buts that's before the trottle plate. I'm not expecting that to be the problem, but I'd be a dummy not to replace it

The VIS switching valve was actually stuck in the closed position, and wouldn't open the first several times. I jolted with 12 volts and it finally started working. huff.

Charles
 
Old Jun 15, 2006 | 12:15 PM
  #19  
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OK i did the running vacuum test. -17lbs, and remarkably stable with less than 1Hg fluctuation.

Should it be closer to -22?

The only thing I know to do is to replace the marginal operating parts and retest. I mean nothing is completely broken, but there are a couple of weak points I could strenthen.

What else IS there?

Charles



 
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