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240 Just failed CA smog, high NOx

They check timing at idle though, before the car goes on the rollers. I think Luke means they will allow anything under 1200rpm idle speed for that part of the test.
 
They check timing at idle though, before the car goes on the rollers. I think Luke means they will allow anything under 1200rpm idle speed for that part of the test.

Ah okay, still don't know how me advancing the timing by turning the distributor left ended up being 6? according to the smog test.
 
first off, you need a timing light... at the higher rpms I'd bet your timing is crazy advanced, like 25? or more... I mean come on, you blew a "1" NOX at 1500 rpm and them an 800 at 2500 rpm... right??? Plugging the vacuum at the ignition computer keeps the advance way down, more like a normal curve.

Also, I just ate a burrito, chicken, beans and pico and it was delicious
 
first off, you need a timing light... at the higher rpms I'd bet your timing is crazy advanced, like 25? or more... I mean come on, you blew a "1" NOX at 1500 rpm and them an 800 at 2500 rpm... right??? Plugging the vacuum at the ignition computer keeps the advance way down, more like a normal curve.

Also, I just ate a burrito, chicken, beans and pico and it was delicious

I'll hopefully have access to a timing light on the weekend when I do my oil change.

Congrats on the burrito, very customizable and delicious thing to eat. We just had tacos.
 
Okay fresh oil change done, a gallon of Rotella T6 and a black Mahle filter. We think the timing is set to 10, we're not exactly sure.

The timing marks we saw looked like this: http://b0.img.mobypicture.com/38fd0800a6096a3ed6bf269c31be2e80_view.jpg

We set the notch on the crank pulley to line up to the 10? mark at idle. Then on his fancy timing light, we did a check where we "added" 10? and the notch lined up with the 0? mark all the way to the right, which we assume is TDC. When we revved the car, the notch moved over to the mark just to the left of the 10, which we think is 15?.
 
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The photo you linked shows the notch lined up with 0 degrees meaning the crank is at TDC for cylinder #1. From your description it sounds like you timed it correctly. You want the static timing (meaning the reading at idle speed with no advance) to be right on the 10 deg. mark in this case.

38fd0800a6096a3ed6bf269c31be2e80_view.jpg
 
Then I guess we timed it right. Now I'll just drive around to get the O2 sensor working and then do the next smog check maybe Tuesday/Wednesday. The exhaust still crackles like pop corn, not sure if that's a good thing or not. Sounds great.
 
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E85 Ethanol

Cali gas is already E10.

E85.... Old Volvo don't care! It won't hurt anything. It burns very clean. I plan to run it once I turn up the boost. It's equivalent to high octane gas, but it lowers the MPG.

Sidestory: New cars can throw a lean code if FILLED with E85. I have a fuel tester at the shop. I had ONE modern car in the last couple years with a P0171 and P0172 and it was backfiring thru the intake lean. All checked out until I got the analyzer out and the fuel measured exactly 85% Ethanol.
 
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Sidestory: New cars can throw a lean code. I have a tester at the shop. I had ONE modern car in the last couple years with a P0171 and P0172 and it was backfiring thru the intake lean. All checked out until I got the analyzer out and the fuel measured exactly 85% Ethanol.
So running E85 made the car backfire through the intake? Damn. Did it cause a lot of damage?
 
It was a direct injection modern V6. It just ran like crap and was very lean. +40%, or so, fuel trims with no air leaks found. Check engine.light on. I scratched my head for a while on that one until I took a fuel sample and found E85 in the tank. I think Grandma wanted to buy the cheap **** at the pump and picked up the yellow handle... I just ran it outta fuel until it stalled and filled the tank with gasoline.

Note: backfire thru the intake can indicate a lean condition.

Back on topic: try some E85 OP and post back with the numbers! I wanna see how clean she blows.
 
I'm still 3/4 full on 87 gas, not really sure if I want to siphon some out to fill up on e85. I just need to drop my NOx at 25mph by 83ppm, which I think I'm fine now since I did an oil change and retarded timing to 10?, while also blocking the black box diaphragm so it doesn't advance the timing too much when they rev up for the 25mph test.
 
Make sure the engine is breathing cold air only. A cooler mixture has lower nox. You could probably just rig the inside of the air box to only have the cold side open. Then it would be not be seen under visual inpection.
 
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The cats inability to reduce NOx and the fact that it's backfiring both point to an exhaust leak. Cold air being drawn in through a leak will cause both issues.

E85 may make the mixture too lean and actually increase NOx. I wouldn't recommend it.

5-gas-chart_btm.png
 
The cats inability to reduce NOx and the fact that it's backfiring both point to an exhaust leak. Cold air being drawn in through a leak will cause both issues.
Yeah I've been battling with a possible exhaust leak. Already replaced all gaskets and piping from the front pipe back. Checked my manifold and see no visible cracks, front pipe is less than a year old. My dad and I welded on an OEM Volvo 240 turbo exhaust with the new cat and checked for leaks. But I have always been hearing the hissing sound when accelerating at the passenger side. I can try and make sure all piping is tightened well before doing the test.
 
Make sure the engine is breathing cold air only. A cooler mixture has lower nox. You could probably just rig the inside of the air box to only have the cold side open. Then it would be not be seen under visual inpection.

A moot point over the thermostat's 80? target temperature which I'm sure it is now during most of the day in LA.
 
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