Gas additives reduce NOx? - PeachParts Mercedes-Benz Forum

CamelotShadow · #1 07-04-2013, 09:42 PM

Dealing with a euro 83 500 sec that failed NOX smog.

Getting parts to tighten up vacumms.

Was perusing a local auto shop
Sears & my eye came upon

Lucas productts. Someone had recomended them but I'm not sure.

Lucas Deep Cleaner for Fuel injectors & combustion chamber.

Specifically said will reduce NOX.

Lucas Oil Deep Clean Fuel System Cleaner : Lucas Oil

Anyone know if this snake oil is safe & effective w MB?
How does it compare with the Chevron Techron cleaner? Have added that from time to time but not recently?
Just wondering if they were similar?

Lucas also come with a gas additive which I bought
which seemed to be useful???

Lucas Fuel Treatment : Lucas Oil

ps2cho · #2 07-05-2013, 12:59 AM

To get my wagon to pass borderline NOx I dumped 6 bottles of ISOheet into half tank of gas. Rubbing alcohol achieves the same thing, but I wanted to take it easy on the fuel system. I put in that Lucas product before the emissions and it certainly didn't do as much as the Isoheet. Spend the money on the isoheet than the lucas additive.

oldsinner111 · #3 07-05-2013, 05:12 AM

iso heet or e85 50% works

CamelotShadow · #4 07-05-2013, 08:34 AM

is just alcohol
sort of like rubbing ispropyl .70?\

Hmmm might pass on that.

97 SL320 · #5 07-05-2013, 10:19 AM

Nox is caused by high combustion chamber temperatures, in this environment Nitrogen is fused with Oxygen.

Is your EGR system working? When exhaust is recirculated into the intake combustion chamber temps drop.

There may be timing / fuel mixture causing high temps, have a look around the net for a emissions curve that shows fuel mix vs CO , CO2 , HC and Nox to get some idea what is going on.

CamelotShadow · #6 07-05-2013, 06:01 PM

Quote:

Originally Posted by 97 SL320

Nox is caused by high combustion chamber temperatures, in this environment Nitrogen is fused with Oxygen.

Is your EGR system working? When exhaust is recirculated into the intake combustion chamber temps drop.

There may be timing / fuel mixture causing high temps, have a look around the net for a emissions curve that shows fuel mix vs CO , CO2 , HC and Nox to get some idea what is going on.

EGR was checked by a mechanic & by myself & it opens.
I did find a cracked red ruv=bber hose connecting it to the egr vac line.
I replaced that.

I have some old rubber hoses leading to intake I will be switching for new ones.

The engine does run hot 90C.

I have to call around to see what smog repair shops will be able to diagnosis a 30 yo car.

I'm getting a temp gun.
What kind of operating temps of various componemts should I detect?
Can this help w detecting problems?

NOx seems to be a tricky one for the emissions to handle.

Thanks

ps2cho · #7 07-05-2013, 07:51 PM

How much did you fail NOx by?

You can't hand over these cars to anybody otherwise expect to pay them to learn your car.

97 SL320 · #8 07-05-2013, 08:15 PM

Quote:

Originally Posted by CamelotShadow

EGR was checked by a mechanic & by myself & it opens.

It needs to open and flow exhaust into the intake. On most cars, manually opening the EGR at idle should stall the motor ( or at least make it run very rough ) If not there isn't enough flow.

Quote:

Originally Posted by CamelotShadow

I did find a cracked red ruv=bber hose connecting it to the egr vac line.
I replaced that.

Also make sure the EGR opens by vacuum when it should, ( usually part throttle with the engine loaded, just like distributor vacuum advance )

Quote:

Originally Posted by CamelotShadow

The engine does run hot 90C.

I have to call around to see what smog repair shops will be able to diagnosis a 30 yo car.

I'm getting a temp gun.
What kind of operating temps of various componemts should I detect?
Can this help w detecting problems?

NOx seems to be a tricky one for the emissions to handle.

Thanks

Engine temp is less of an issue, it is high combustion chamber temp that causes high Nox and something you won't be able to measure.

If this car has a 3 way cat it might be failing resulting in high Nox.

I haven't read these but they should apply.

www.magnaflow.com/07techtips/TechBulletin/TB80013.pdf

www.bearriverconverters.com/data/CatOpp.pdf

CamelotShadow · #9 07-05-2013, 09:10 PM

Quote:

Originally Posted by 97 SL320

It needs to open and flow exhaust into the intake. On most cars, manually opening the EGR at idle should stall the motor ( or at least make it run very rough ) If not there isn't enough flow.

I have some instructions...I'll have to try this again.
I dodn't know if I was able to complete the test as the old egr rubber was fused at vac line to egr valve
I was able to re move it with aid of heat from hairdryer

Quote:

Also make sure the EGR opens by vacuum when it should, ( usually part throttle with the engine loaded, just like distributor vacuum advance )

not sure

Quote:

Engine temp is less of an issue, it is high combustion chamber temp that causes high Nox and something you won't be able to measure.

If this car has a 3 way cat it might be failing resulting in high Nox.

My guess is cat is old& will try to take its operating temp when I get the temp gun

Quote:

I haven't read these but they should apply.

www.magnaflow.com/07techtips/TechBulletin/TB80013.pdf

Good stuff guess hope its a vac leak making it lean, exhaust pipe leak is also a good possibility...do they mean exhaust pipes?
Also have to see what a idle hose is thats sticking out. Some say rement of a old washush sp? heating system.

Quote:

www.bearriverconverters.com/data/CatOpp.pdf

So a/F ratio...would that also be affected by vacumms? or is it just an adjustment of fuel ratio?

Guessing both.

WSell first thing is to try to change more rubber parts that I can do myself & see what that does.

Also check the EGR line.
I have tubing ordered & could change out the entire line.

Hmmmmmmm it all helps & its best I learn on the car not a tech

Thanks!!!

CamelotShadow · #10 07-05-2013, 09:29 PM

would a 500 sec 1983 have one?
There is a large black cannister then a small valve near front drivers side I don't know what it is? charcoal ?

tubing on black cannister (charcoal ? )is hard
need about 6mm id tubing.
Don't think this would affect the engine

Would love to know what that small valve connected to yellow vac line is

CamelotShadow · #11 07-05-2013, 09:58 PM

I faile NOX in 2009
replaced o2 senser ^ then it passed flyin colors with Nox.

Could my O2 senser have failed after 4 years?

Maybe it just doesn't work on the electrical end?
How does it affect the system?
I would assume it has to cut or vary air somehow?

CamelotShadow · #12 07-05-2013, 10:00 PM

Quote:

Originally Posted by 97 SL320

Nox is caused by high combustion chamber temperatures, in this environment Nitrogen is fused with Oxygen.

Is your EGR system working? When exhaust is recirculated into the intake combustion chamber temps drop.

There may be timing / fuel mixture causing high temps, have a look around the net for a emissions curve that shows fuel mix vs CO , CO2 , HC and Nox to get some idea what is going on.

Does a hot EGr tube & valve mean anything?
This is on the engine?

its a euro engine so its different in some ways

The idle control valve is a air slide not electronic ignition as it was changed sometime in the life on the car.
This idle control valve was used on the 450 SL engines...wonder if this is adding to it??? I changed some rubber hoses in that area. Don't know how to get out the hose from the aux air slide valve to intake. May have to remove vlve so will leave that to a tech

Found a cracked hose connected to a valve on back of intake manifold. that is also big tubing I don't have so will have to adress it...

This wouldn't make it run great.
Hoses are hard. Will have to get around to have someone change the hose over the 4 valve ports.

Trying & it does seem to be running smoother

CamelotShadow · #13 07-06-2013, 07:57 PM

83 seems to list this part. I dodn't know where it would be
I haven't seen it so maybe I don't h ave it?

CamelotShadow · #14 07-06-2013, 08:20 PM

Took apart most of the rubber hoses
well maybe half of the ones I could get access to.
Started about 7pm & finished after 2AM.

Had a dog of a time getting one hose w spring clamo on.
I just don't have the reach & strength
I did it but oh my aching back.

Found that cracked hose that connects behind intake on pass side.
Will have to fix that.

Time for a run...I slept in late & I'm limping around.

Still got some grease under my nails..

Oh, its not very lady like but I love my car & want to make it better.

Thanks for all the help.

97 SL320 · #15 07-06-2013, 09:00 PM

Post 10

US spec cars from the 70's and up have a vacuum diagram posted somewhere under the hood, not sure if Euro spec cars did the same. A repair manual should show vacuum diagrams.

Post 11

The O2 sensor looks at excess Oxygen then feeds that info back to the engine computer, the fuel mixture is then adjusted accordingly. This is called a closed loop system.

Post 12

A hot tube / EGR valve test is only valid when the engine is cold and the valve is opened. When running, everything under the hood will heat soak making the test less valid.

Stalling the engine / rough idle when the EGR is opened is a good test.

Post 14

" Late night in garage . . . .

. . . .Started about 7pm & finished after 2AM. "

" Time for a run...I slept in late & I'm limping around.

Still got some grease under my nails..

Oh, its not very lady like but I love my car & want to make it better. "

Working on your own car, on a Friday night, will you marry me?

(Latex or nitrile gloves go a long way to help keeping hands clean. )