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salewit

My car throws fits when smog test is due!

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Here we go again. 92 Legacy. Some might remember me from a couple of years ago when my car repeatedly failed smog. The problem was finally fixed, and I went in this year with confidence that the thing would pass easily. It didn't.

 

It actually passed all the emmissions tests, but failed on a technicality. The CEL light was on. I had no idea I would get failed on this. This was illuminated from the problem 2 years ago and I just never bothered to clear it. Or so I thought.

 

I took the car home, disconnected the battery for half a day. Reconnected it, and the CEL is still lit. I checked the code and its 31.

 

Investigated the TPS and I'm getting weird stuff. The idle switch (Pins 1&2) works perfectly. But test 2 which is to backpin #2 and #4 of the connector with ignition on and the connector connected, is not behaving. I get virtually 0 volts (.03) closed, and about .05 wide open. I triple checked my back pins (with an ohmeter) and they're definitely making contact. I tried checking from #4 to ground and I got the same thing. I pulled the connector and then checked #4 to ground and I get about 3.4 volts!

 

It's almost like the TPS is shorting to ground. But then why do I only have 3.4 volts on pin 5? Everything says it should be 5v. Pin 1 to ground by the way *IS* 5.0 volts.

 

The car has been running smooth as silk, and my emmission numbers are excellent. Just need to get the CEL light out. And I assume smog will check to make sure the light comes on with ignition on and off when car starts. So I can't just remove the bulb.

 

Help!

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And I assume smog will check to make sure the light comes on with ignition on and off when car starts. So I can't just remove the bulb.

 

Help!

 

So rewire the bulb to come on with the oil pressure idiot lamp. They will both come on with the bulb check and assuming you have oil pressure they will both go out when the engine starts :)

 

I agree with you - if it isn't broke, don't fix it. Make a mental note of it and make the wiring connections easily accessible so you can change it back from under the dash but don't needlessly spend time and money fixing a problem that's essentially a technicality - especially if it's not bothering you.

 

GD

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Wow you know that may just be the best advice I've gotten on any forum anywhere! Thanks so much. It does concern me that the unit doesn't test correctly, but like I said, the car is running like silk, and my emmission stats were about 85% lower than the maximum.

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No problem.

 

See - it's all about the warm and fuzzy feeling. You feel W&F, and so do the bunney huggers and the guy that tests your car. It's all about perception and when you are dealing with these type of people you just have to cater to what they want - they want the *appearance* of cleanliness and functionality.

 

I feel for you man - if I lived in CA, I could easily see myself yarding out my "modified" engine every time I had to run through the test station and installing the stock plant.

 

GD

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