91 300E fault code 16
 

Background:

About a month ago, took the car into the mechanic for the check engine light. He said it was the ERG, checked the valve and said the valve was OK. He then cleared the line by blowing some compressed air into the line. He said if the light went on again, he would replace the line. The bill was $200.

Sure enough, the light comes on again, about a week later. This time, with the help of this forum, I cleaned the line out myself "roto -style " with a wire cable and drill. Lots of black stuff came out, and she actually ran better, perhaps my imagination? Reset the check engine light by disconnecting the battery.

Suddenly, the check engine light comes on again this week. Now that I learned where and how to read the codes, the flashing fault code is 16. Is 16 related to the ERG, like the valve is truly faulty, or is it something else, like a wiring harness problem?

16 is the EGR code. If the pipe is clean it could the valve - easy enough to replace, maybe a little pricey.

OK, thanks. What a PITA this erg thing is, wish I could just disconnect the darn thing....

Another idea I found:

Before you try to clean the valve which probably os ok.... test it 1st. Have the engine at idle.
Disconnect the hose from the valve. Apply vacuum to the valve with a hand pump if you have access to
one. If not, you can get manifold vacuum from the nipple on top of #6 intake runner.
With vacuum opening the egr valve, your idle should be very rough.
If yes: you have a tired catalytic convertor.
If no: 9 out of 10 times, the tube is plugged between the valve and intake.
http://cars.mylounge.com/archive/index.php/t-134847.html

Comments?

More on EGR testing:

http://www.peachparts.com/shopforum/tech-help/161017-95-e320-rough-idle-above-4000rpm-4.html?highlight=E320%3A+Rough

EGR code 16 simply means the EGR system is not working. You want to check the SOV and vac line feeding the EGR . If that has no vac , you will have no egr valve actuation.
The EGR test you mention is egr flow test by you manually open/closing EGR..if that attempts to stall engine, you know the valve and passage to the intake are OK, but you do not know if you have vac/sig to operate the valve b/c your manual test by-passes those inputs of the system..

Do you have the 16 or 8 pin diagnostic connector box??

Do the checks and see if all seem OK
May also be carboned up..a good run up a hill under load in 3rd may clean it up.

16 pin

Light is still off, so we must have done something right...:D

Where do you find the fault code?
 

I have a 91 300e with 251 K and ever so often the check eng lamp will come on for about a day then go dark for weeks or more. I have never seen any fault code. I thought you had to have a computer interface for that.

New to here

Try a search above for "fault code reader", etc. - should turn up lots of threads, lots of information.

Mine has a small black box near the battery - take the top off. I push a (silver?) button (2 -4) seconds, then count the flashing lights.

Do you have a Californian model?

Yes, I think so. Was purchased in CA.


Update: Light went on again. This time I used a longer (about 2 1/2 ft) piece of thinner cable with a drill to clean out the tube. Put it all back together, but noticed a puttering sound upon acceleration.

I'm thinking air is getting inside or something like that. Researched this forum. So I ordered a egr valve gasket as the old one was like disintegrating paper. Sounds perfect now, and light is still off (knock on wood)!

Thank you for all your helpful posts! I could not have done it myself!:)

Code 16
 

You need to understand how the ECU tests the EGR system!
With the engine at operating temperature the ECU monitors manifold vacuum via the Piezo pressure sensor in the EZL (electronic ignition) and when declerating will open the EGR valve, It is looking for a change in manifold vacuum corresponding with the operation of the valve.
If the vacuum line from the manifold to the EZL module is bad it won't see this pressure change and will set the light. Change the the vacuum line.
Good luck and please post your fix.
Mike