1985 mercedes failed emissions what could it be?

Question

the hydrocarbons failed by a point loaded and at idle passed but co failed over 3 percent i have a leaking fuel pump but i dont know if thats the only problem

Answer 1

For Hydrocarbons you need a new catalytic converter..... for CO I would change the spark plugs and a new air filter.

Answer 2

Firstly, try a new set of plugs and an oil and filter change. That fuel pump leak could cause the engine to run lean, but as long as it doesn't backfire out the intake you shouldn't be failing due to that. If plugs and oil don't do it, try running a thicker oil than recommended (e.g. 10w - 40, SAE 30). If the car has a carburettor, rebuild it or get someone to do it. If it is fuel injected, try an injector cleaner such as techron.

Also, a product called Sea Foam (available at Autozone for $5) can be very helpful for getting thru emissions when delivered thru brake booster vacuum line. You just slowly pour thru half a can with the engine running. Then shut off the engine, dump the rest of the sea foam into the gas tank, then start it up again in 5 minutes. There will be a LOT of smoke. Just keep idling it til it stops smoking.

Finally, if all else fails, add 2 bottles of CD2 Stop Smoke to your oil and drive on the highway for 30-60 minutes. By now you will probably get through emissions.

Answer 3

I don't think the fuel pump would do that.

Did you pass the NOx, if you did, or if your state doesn't care about that, then you will be ok.

put some new spark plugs in it, and if the spark plug wires are more than 10 years old, replace them.

Also you can get some of that smog check stuff, dump in the tank, drive for a couple of days and get the check while it's still in the tank. It should pass.

but if your NOx is close to the limit, then new spark plugs and the additive, could put that over the limit.

Does it have a carb. it might need rebuilding, does it have a smog pump, that might need replacing.

Answer 4

It could also be the fact that cars made in 1985 aren't designed to meet the emissions requirements in places like Northern Illinois, California, and the North East. The problem may lie in that, and you would need a new car.

Answer 5

I also have a similar authentic motor vehicle. those automobiles would not have adjustable timing. so the situation isn't from the timing. If the pc did no longer provide you Oxygen sensor code meaning its no longer the Oxygen sensor. the only element and maximum uncomplicated element you will possibly pick to be sure is the gas Air mixture that's adjusted by skill of the gas distributor. The CO2 point could be adjusted to the manufacture everyday then you do not have a situation with the NOX analyzing.

Answer 6

fuel press. can effect the co readings but I would probably think that the o2 sensor is either week or bad.

emissions tech 5 years

Answer 7

Catalytic converter possibly breaking down and wearing out? Do you have any check engine lights on? And if so you should have them checked out. We don't have emission test here so I don't know the routine for them.

Answer 8

Bad Car

Answer 9

the cat converter, or an exhaust leak