I have a 1999 SL (plain vanilla SL), which has been a great car for me to go back and forth to work. It has 209000 miles, 5 speed, a/c.

In trying to get it''s California registration for 2009 it won''t pass the smog test, 3 times!

1. First try, the Emissions test passed, however, the CEL came on, it failed. It did not complete the OBD self tests.
   <ul>
2. I cleaned the injectors, bought a new gas cap and took it back to re-test

[*]Second try, failed, not because of CEL (it was off) but Emissions were up. NO was 822 vs 487 max. Also, it was idling on 3 of 4 cyls.
<ul>[*]I changed the plugs (Delco platinum) and new wires[/list][*]Third try, failed, the CEL was on this time (automatic fail) and it was idling high (2K RPMs) and rough. AND the emissions were bad</span>; the NO is now 1061 vs. 487!!![/list]I''ve been reading the forum, and it seems like 1999 SLs need to replace the Throttle Position Sensor...could that be the problem?

Also, the CEL stays on all the time, it used to be intermittant.

I need the car to go back and forth to work, and am driving around with no tags (I paid for them but Cal DMV won''t send the tags until the smog has passed.)

HELP!!!!!!!

Regards,
Crzesk8dad

 

If your CEL is on all the time, you need to list the diagnostic codes so the really smart guys here can help figure out your problem(s) ...

 

So maybe I should invest in an OHD scanner?

 

Well, that would be a start, but sometimes, places like AutoZone will do a scan for free (guess they figure you will buy the parts you need from them). Anyhow, those codes are the first step ...

 

I ordered one for $30 dollars, should be here in a few days....figured it probably would be good to have, since I have 4 cars ranging from 94 to 02.

The Autozone idea is a good one, as well....may do that later, just to get things going. Once I do, or I get the OBD scanner that I ordered, I post and let you know the codes.

Maybe it will be something I can fix...maybe not...at least I''ll know what it may be causing the problem.

Thanks OceanArcher!

 

OK, I got my cheapie OBD scanner. It works pretty good.

Here are the codes:

Fault:
<ul>[*]P0301 Cylinder #1 misfire detected[*]P0507 Idle control system RPM high[/list]Pend:
<ul>[*]P0301 Cylinder #1 misfire detected[/list]Not sure why P0301 is shown twice?

I also ordered and received the throttle position sensor (found it on line for $34, I though what the heck?).

Where do I go from here?

Thanks
Crzesk8dad

 

P0301

Cyl misfire codes on these S cars can be anything from bad plug wires to defective coils to dead cylinders (low/no compression).

Stick to the basics ensure you have spark on Cyl 1
(check plug wire, plug, plug gap, etc.)

From your "running on 3 of four cylinders" + the emissions readings you listed it sounds as if that cyl is getting fuel (which is probably burning in the exhaust system, not the cylinder, but you should still check.
__________
If you have spark and fuel, I would do a compression test on all cylinders.

My suspicion is that you will find low or zero compression on cyl 1

We will worry about the high idle issues after dealing with this one, since you won''t pass inspection on 3 cyls...

 

OK, here is another clue...maybe...

I was going through some paperwork in my glovebox (I keep all my receipts from work done on the car) and found that my last visit to my Saturn dealer (to replace a fan motor), they had noted that my car has an "intake" leak, as well as a possible motor mount needing replacement.

I would expect the motor mount is not causing this problem with the P0301 and P0507 codes, but could the intake leak indicate that I may have a compression leak of some sort?

BTW-the plugs and wires are all good (recently replaced, as noted earlier).

If I have a compression leak, I''m wondering if I should keep the car...it''''s only worth about $1500 per KBB.

I''m open to suggestions from you great gurus of the mighty Saturn.



Edited by: crzesk8dad

 

[/list]Bad intake manifold gasket. Replace it.
CHeck: Spray brake cleaner around each cylinder at the gasket with the car on and listen for changes in idle. If there are then thats your issue. Very common on late ''99 and 3rd gen SOHC. 15 bucks at rockauto.com I can post a how-to with pics if needed.

While your under the hood, replace the ECTS also.

Youll be good to go pass your inpsection after that

 

Thanks to everyone. I had the intake manifold gasket replaced ($385!) but the good news is the car passed smog! YIPPEE! I can drive legally, again.

For those of you handy with a wrench, I''m sure you are thinking why I had someone do it, rather than myself.

Well...frankly I know enough to know that I don''t enough.

Anyway, Happy New Year and thank you to all, once again!