87 260E failed smog...Input? - Page 2 - PeachParts Mercedes-Benz Forum

G-Benz · #16 03-19-2009, 01:43 PM

The high NOx could also indicate a clogged EGR tube...

Merkey · #17 03-19-2009, 01:53 PM

Dont think we have an EGR sytem on this one.

ajme · #18 03-19-2009, 06:55 PM

How many miles? Have the valve stem seals ever been done?

High NOx can be caused by high compression caused by deposits in the combustion chambers. High unburned HC can be caused by the oil running down the valve stems. Time for a head job? It has twice made my aircare numbers a lot better.

Andrew
1989 190e 2.6

ps2cho · #19 03-19-2009, 07:59 PM

I have checked the plugs and there is a little deposit...but nothing more than my 300TE had, and she passed the test fine...So I don't see the "cause" of the failure due to the valve stems.

Odometer is broken at 81k miles. I would make the assumption it is no greater than 120k because the head gasket or front timing chain gasket have not been replaced. Not much on this engine has been done. Even the mixture tower has not been touched. Had to grind off the top today to get at the unit.

Oracle12345 · #20 03-20-2009, 12:16 AM

NOx is too little air and too much fuel so a blocked egr tube could be in question. Any gas or diesel car Ive seen has an egr system on it...

he doesnt have a problem with HC..... he has a problem with NOx.Whenever you have high NOx hydrocarbons and carbon monoxide are down greatly.

ps2cho · #21 03-20-2009, 01:41 AM

Quote:

Originally Posted by Oracle12345

NOx is too little air and too much fuel so a blocked egr tube could be in question. Any gas or diesel car Ive seen has an egr system on it...

he doesnt have a problem with HC..... he has a problem with NOx.Whenever you have high NOx hydrocarbons and carbon monoxide are down greatly.

This engine does not have an EGR.

---

Why is my X11 reading 69.2% and not 70%?

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Fuel pressure looks dead on.
Lower Chamber:

Upper Chamber:

Oracle12345 · #22 03-20-2009, 09:06 AM

your egr is mounted on the exhaust manifold and a switch overvalve is mounted on the wall. Ill take a picture for you. every car has a system in place to do the role of egr whether its mechincal or electrical(electrical egr, variabl valve timing(vvti) like in a lexus/toyota.

60% is road speed at ke control unit is an implausible-test hall effect sensor

70% is no tna signal plauisble, open circuit to ke control unit-test tna signal

btw you are supposed to do that after reading the fault memory @ x11/4

ps2cho · #23 03-20-2009, 09:32 AM

There was no EGR on this model year...In the later models there was one attached to the exhaust...I believe 90 and above? Someone correct me if I am wrong.

Oracle12345 · #24 03-20-2009, 09:39 AM

Quote:

Originally Posted by ps2cho

There was no EGR on this model year...In the later models there was one attached to the exhaust...I believe 90 and above? Someone correct me if I am wrong.

some info on the emission system for the M103

if you dont have an egr valve then someone must of removed it for performance reasons, but an egr should be there

pifcat2 · #25 03-20-2009, 11:03 AM

Quote:

Originally Posted by Oracle12345

some info on the emission system for the M103

if you dont have an egr valve then someone must of removed it for performance reasons, but an egr should be there

I thought my RENNTech engine was unique in that the front exhaust manifold does not have any fittings or an air pump like both my 91's have but my new (to me) '88 300TE as shown also lacks these parts...

Merkey · #26 03-20-2009, 11:39 AM

The '87 260E and his '88 300TE have no EGR system on them and I am pretty sure they have not been changed.

Merkey · #27 03-20-2009, 01:48 PM

Can anone tell me the procedure for setting the Duty cycle on this 260?
The Landis site is kinda vague, and I want to be sure we got it right.
The car runs better now, but has hesitation when you snap open the throttle... almost feels like a misfire.
Maybe we can post a video of the throttle plate when it does this....

We are gonna change the plugleads and cap/rotor , idle and vac pipes arrived too, so by the weekend we will have all the normal stuff done.

Oracle12345 · #28 03-20-2009, 10:11 PM

i remain corrected, the egr system with the air pump and egr valve started in 1991 which is the year of my 190E 2.6 which is interesting. Emissions until 89 was controlled by lambda.

Download Checking on ratio.pdf from FileFactory.com

ajme · #29 03-21-2009, 11:01 PM

There is a lot of misleading information in this thread.

An '87 does not have an EGR system.

This car has high HC and NOx.

High NOx is not caused by richness. It is caused by a lean mixture (unlikely if the system is working properly), too high compression, or a bad catalytic converter.

My guess is cylinder deposits causing high compression. Do an Italian tune-up (full throttle on the highway to maximum revs), or try the "emission-passing magic deposit remover" solutions from the auto store. or pull the head and scrape them off.

High HC can be caused by a rich mixture (unlikely if the system is working), misfiring, a vacuum leak that affects only some cylinders (so that the system tries to compensate and makes the others too rich), or unburnt oil.

My guess is misfiring.

Tackle the basics: new plugs, new plug wires, clean up the cap and rotor, make sure that the on-off ratio is oscillating around about 50% (some say a couple of % under). Make sure that your O2 sensor is ok (there is a checking procedure in the Mercedes CD manual under CIS-E)nand replace it if you are not sure. We are now up to $200, cheaper than going to a repair shop. If your on-off ratio is not oscillating, then it is indicating a fault code, and you had better have a look at the CD manual.

Look in the DIY section for Steve Brotherton's article on evaluating engine controls. It is very thorough on the on-off ratio and EHA.

Your meter does not indicate exactly 70%, because it is not an accurate meter. My Sears meter also is a little off. Don't worry about it; just make a mental adjustment.

Our 190e 2.6 passed aircare yesterday with flying colours, at 370,000 km (about 230,000 miles). It recently needed a new fuel distributor. It had a recent O2 sensor. It has old plugs, cleaned, filed and gapped. It has the original catalytic converters. I just broke down (against my better judgement) and put in a new cap and rotor, replacing the originals. Otherwise, just the basics. Yours has much less miles on it, and is unlikely to have any fuel injection components worn out. Just the basics.

Andrew
1898 190e 2.6

Oracle12345 · #30 03-21-2009, 11:09 PM

Quote:

Originally Posted by ajme

There is a lot of misleading information in this thread.

An '87 does not have an EGR system.

This car has high HC and NOx.

High NOx is not caused by richness. It is caused by a lean mixture (unlikely if the system is working properly), too high compression, or a bad catalytic converter.

My guess is cylinder deposits causing high compression. Do an Italian tune-up (full throttle on the highway to maximum revs), or try the "emission-passing magic deposit remover" solutions from the auto store. or pull the head and scrape them off.

High HC can be caused by a rich mixture (unlikely if the system is working), misfiring, a vacuum leak that affects only some cylinders (so that the system tries to compensate and makes the others too rich), or unburnt oil.

My guess is misfiring.

Tackle the basics: new plugs, new plug wires, clean up the cap and rotor, make sure that the on-off ratio is oscillating around about 50% (some say a couple of % under). Make sure that your O2 sensor is ok (there is a checking procedure in the Mercedes CD manual under CIS-E)nand replace it if you are not sure. We are now up to $200, cheaper than going to a repair shop. If your on-off ratio is not oscillating, then it is indicating a fault code, and you had better have a look at the CD manual.

Look in the DIY section for Steve Brotherton's article on evaluating engine controls. It is very thorough on the on-off ratio and EHA.

Your meter does not indicate exactly 70%, because it is not an accurate meter. My Sears meter also is a little off. Don't worry about it; just make a mental adjustment.

Our 190e 2.6 passed aircare yesterday with flying colours, at 370,000 km (about 230,000 miles). It recently needed a new fuel distributor. It had a recent O2 sensor. It has old plugs, cleaned, filed and gapped. It has the original catalytic converters. I just broke down (against my better judgement) and put in a new cap and rotor, replacing the originals. Otherwise, just the basics. Yours has much less miles on it, and is unlikely to have any fuel injection components worn out. Just the basics.

Andrew
1898 190e 2.6

already mentioned the info on what causes NOx. The car failed for NOx and hydrocarbons true but taking care of one will take care of the other.
The best and only way to clean carbon depoists from a motor is to use atf. All the other stuff on the market will screw up bearings etc and you cant get it out of the engines 100% completely. the m103 is a high compression motor since it require premium fuel only. Can carbon depoists be adding to the already high compression sure.

his lambda ratio is over 50% which explains the high HC's. Doing a tune up would help the problem but may not solve problem. Adjust the lambda ratio and pull a spark plug to see how its running.