Smog Issues, what would you look at next?
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From: Northern Cali
W124
Smog Issues, what would you look at next?
Hey guys, I'm having a hell of a time getting the 260 to pass smog. I've already replaced the catalytic converter and the O2 sensor but still no go. What would look at next?
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what reason? smog station have to tell you what code..
as i know 1995 below easy.... dont have connect the computer to OBD plug in........
tks
steve
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if youhave new plugs and wires already in addition to the 02 sensor and cat, make sure you get the car nice andhot before you get the test done. and i dont mean let it idle, i mean give it the old italian tuneup, a good hard (preferably longish) blast on the road, then take it straight to the test. make sure you dont wait too long to get it tested.
cats are most effective when they are hot.
cats are most effective when they are hot.
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From: Covington wa
05 SL500, 02 BMW Z3 (Mrs. VF), 05 FJR1300, 91 ZX-11
What are the test results? Is it failing HC, CO, CO2??? Sticky or stuck EGR valve is a common cause of emissions failure. In higher mileage engines, leaky valve seals letting oil into the intake ports or exhaust are a common cause.
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Thread Starter
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From: Northern Cali
W124
Plugs, wires, cap and rotor all new. There's no EGR valve on this model. I'm guessing the smog pump because it does make a ticking sound from time to time when I start the car. I usually shut it off and turn it back on and that ticking goes away. It can sometimes take a couple tries for it to go away.
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From: Socialist West Coast
95 E320, 19 Ram 1500 Hemi, 21 GLS 580(wife)
I believe the air pump/smog pump is only really used upon start up, until the engine is warm... correct me if I am wrong. This would be one more reason to try it after a good work out/italian tune up when the car is really warm. I have also seen bottles of stuff you can dump in the tank right before such a test. Also, try running some fuel system cleaner through the car.
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From: Long Beach, Ca
lots of cars
Try adjusting the a/f ratio and leaning the car out by adjusting the EHA valve....also try running a hotter spark plug and that should improve some but you gotta lean it out depending on the smog test results.....
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From: Northern Cali
W124
I did run the car for about 30 min. up and down the freeway before bringing it to the shop. I've also tried "guarantee to pass" smog additives the first time but that only works on carbon deposits and that sort. I only tried it because I'm getting desperate. I work for Kragen and that stuff only works in mild cases. If you're experiencing really bad fuel issues its usually something more serious than dirty injectors.
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From: Northern Cali
W124
Another thing to note, it got better when I installed a new cat but still failed. When I installed the OEM O2 sensor (not the converted mustang one) it got worse. I'm really stumped. I have a buddy who's gonna see if he hook it up with a diagnostic at his shop or maybe even "talk" to the smog guy but I'd rather it pass legit so I don't have to worry about it anymore.
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From: Portland Area
2000 C230K and 2002 ML320
I had a problem passing too... not in cali... but, my shop leaned it out and replaced the O2 sensor... he also told me to go early in the day, make sure the car is at op temp... and that waiting in lines causes the cat to cool down and not work properly and will fail almost every time... so I did that... and held the pedal to keep the cat hot, and I passed with flying colors... oh and Shell V-Power helped a little too I think... good luck with this
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From: Anaheim
MB 300E | BMW M Coupe
i had a similar problem......i took it to a mechanic and he said the same about how it needs to be really hot before tested....it was tough to pass...supposedly they "cleaned the fuel system" and that was it.
if you need more repairs, apply for the state program that helps you out with the costs.....
-OG
if you need more repairs, apply for the state program that helps you out with the costs.....-OG
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From: Seattle
1990 300ce
^^I did that while waiting in line for emissions recently. One of the workers came out and *****ed at me because she said it was too loud and obnoxious. I failed emissions miserably...
I took mine to the mechanic and they adjusted it. The car aced emissions, but was hardly running... so annoying. So I took it back to me regular mechanic and he said they had the fuel mixture so messed up that the car was barely able to run!
Anyway, my point is... I wouldn't throw parts at it. Try making adjustments first.
I took mine to the mechanic and they adjusted it. The car aced emissions, but was hardly running... so annoying. So I took it back to me regular mechanic and he said they had the fuel mixture so messed up that the car was barely able to run!
Anyway, my point is... I wouldn't throw parts at it. Try making adjustments first.
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From: Northern Cali
W124
Thanks folks, I'll try having the mechanic run some adjustments. I think thats what my uncle (previous owner) did and after it passed he set it back to a drivable setting. I'm going to try that state smog aid thing and see what they can do. I don't have to do it for real until march but I just want to get a head start.
