1993 400e EMISSIONS HELP!
 

I have now failed VA state emissions twice now. After the first time I bought this emissions solution, used that and drove the car plently. I brought the car in hot to get tested (first time was cold) and the numbers are almost identical. Please look these over and throw me some sort of help. (Tune-up was done recently)

================== Test 1 =============Test 2
========= IDLE 2500 ===== IDLE 2500
====== Limit Reading Reading Reading Reading
HC ppm 125 555 351 553 283
CO % --- 1 7.65 4.39 7.53 3.53

I was thinking it could be the O2 sensor, but I think that will only help CO2. Please post anything that might help, I'm desperate!

bump this cause I'm really hurting for answers

anyone know anything about emissions in general?

I really don't know much about smog stuff but if you want I can post my numbers for you.

When I took mine in I failed due to gas cap suction but luckily the smog guy had several new mercedes gas caps so he gave me one and it passed.

High CO and HC indicates an excessively rich mixture, so the first thing I would look at is the "duty cycle" and O2 sensor health. Search these words on this site.

Also read the following thread and the threads it references:

http://www.peachparts.com/shopforum/tech-help/117048-successful-ca-asm-emission-test-ke-fuel-system.html#post833484

You're going to have to make a major investment in educating yourself on general emssion control technology and issues and the specific emission control technology/systems of your car, which are somewhat complicated.

You might be better off finding a professional who understands these cars. (This may not be easy, either.)

The problem might be something as simple as adjusting the duty cycle, or there may be major problems that could cost hundreds or even thousands to repair.

Mileage and history are important. What is this car's previous emission test history? Does anything appear to have been tampered? These are some of the questions you need to research.

Duke

mileage is high, 160K
however, last emissions the record shows it was so low, literally close to 0 on almost all tests. this was a huge increase. The throttle something was recently replaced because it was idling high. I am thinking it is just an adjustment, would replacing or rebuilding something in the throttle controls be a likely cause for this?

the car honestly has had near perfect tests in the past, it is boggling my mind

what were your numbers zero?

Something has happened since the last test, and I suspect it's in the Lambda system. Like I said previously, it could be something simple - like a connector not connected - or it could be complicated. I would not even hazard a guess without first doing a visual inspection looking for things like disconnected or not fully seated electrical connectors, and then doing some diagnostics like checking the duty cycle and scoping the O2 sensor wave form. Even if you don't have a "check engine" light, check the system for error codes. You need to familiarize yourself with the Lambda system including its OBD - lots of information including diagnostic tests you can download from the two service information sites - then start doing diagnositics.

Just guessing and replacing parts willy nilly is a losing propostion.

My recent California ASM emission results are in the link I gave in my first post. You should start by reading it and then look at the links in that thread.

Duke