I'm guessing this might be the area to discuss this. Mods please move to where you see fit.

So my car was sitting for a year in my garage, where there was some major renovations. After about 6 months, when they completed, I went down to see the condition of my car. It was parked only a few feet away from the reno area. Even though they covered the area with plastic sheeting, my car still had a crap load of dust from the reno all over it. Including under the hood. I cleaned up the car, did a complete oil change and put half tank of new fuel to the already less than quarter that was already in there. I didn't drive it on the highway though to burn off the carbon build up in the lines. Needless to say I failed the CO2 portion by 0.84 over my limit (everything else passed). I was told to put the CRC "guaranteed to pass" in full tank drive it empty and refill just before I test again. I couldn't use up the whole tank before I could test again (I'm on a time constraint with this due to my temp reg sticker expiring in a couple of days, and won't be able to renew for another year when it does). I got to half tank, then refilled and tested. It failed again, but got it down so that I was only 0.25 over my limit. I was told by my mechanic friend that I should add about 4L of Methyl Hydrate to my full tank and drive for a while to heat up the car just before I go test a third time. That it should help with getting me to at least my limit. Checking the forums, this seems to be an advice a number of people have suggested as well.

My main concern now though is, I've been reading that too much methyl hydrate will dry out my o-rings in my fuel injectors if I leave it there for too long. If I fail emissions a third time, my car will be sitting for another year. So my question is, should I have concern with leaving my full tank (70L) with 4L of methyl hydrate in it for another year? Or is that ratio safe enough that it won't mess up my rings in the fuel injectors? What is a safe ratio for this? As well as to help pass emissions test?

Thanks.

 

Do you only drive the car once a year?

What type of fuel is available in your area. Fuel containing alcohol tends to break down fast resulting in water in the tank. You might add a fuel additive that will what could be excess water in the tank. 4L of methyl hydrate may be too much, 1 cup per tank should be enough.

If the car does run your best bet may be to remove as much of the old fuel from the tank either by siphoning or driving the car, then refill with fresh fuel.

Depending on where you live fuel may be available that does not contain alcohol, check the internet pure-gas.org. If storing the car for a year this type of fuel would be best combined with a fuel stabilizer additive.

Do you mean CO rather then CO2?

 

No. My car was out of commission because of my brakes, and I procrastinated fixing it. Had other means of transportation. Finally decided to fix it, but my registration sticker had already expired and I have to get an emissions test before I can get it registered again. Hence the why I'm trying to get my car to pass. Not exactly trying to clean out my fuel line, I'm trying to get my CO reading down by 0.28 to pass emissions. Putting methyl hydrate in my fuel and driving around for an hour before testing, was a suggestion by a number of people that said it should be enough to get it down to my limit. I was just concerned that if I failed again, my car would have to sit for another year, because I've already renewed my temp sticker twice. Where I'm from, your only allowed to renew your temp sticker two times within a 365 day period. It expires in 2 days, so needless to say, I won't be able to drive it again until I can get another temp sticker next year. So if it sat for such a long period of time with almost a full tank, with methyl hydrate in it, it may not be good. Depending on the ratio. Which is what I'm trying to figure out is a safe ratio. 4L to 70L is pretty small, but I don't know how 4L of methyl hydrate would affect my o-rings in the injectors. No one seems to have an answer as to a safe ratio that I can just leave the gas in the tank. That's why I'm asking here.

Yes, that would be correct. CO.

 

Let's concentrate on passing the test first.

Not being a fuel expert can only speculate.

Methyl hydrate is methanol.

Addition of 10% ethanol to gas is supposed to reduce CO emissions by 25-30%. Is more alcohol then 10% better I don't know.

The 1998 was most likely designed to operate on no more then 10% ethanol, check owners manual. Does the fuel in the tank contain ethanol, if so how much?

Automakers have stated they will void a cars warranty if a car built to operate on 10% ethanol is operated on 15% (as proposed by some alternative fuel proponents). Thus 10% seems OK, 15% no.

Add 4L of methanol to what may be fuel in the tank which might contain 10% ethanol and determine what percentage overall of alcohol this is. Alcohol content beyond what the car was designed to operate can damage components, seals, etc. The cars engine computer may not be able to adjust for percentages of alcohol beyond what is designed for.

If you go to the autoparts store and look for fuel additives that are supposed eliminate excess water in the tank the quantities suggested to be used are small.

No gasoline based fuel is going to last 1 year without breaking down and the life of ethanol fuels is much shorter. Fuel additives are not going to magically make bad fuel as good a new.

The car did sit for a year. If it had alcohol or not in the fuel (now breaking down with age) many things can happen.

High CO is caused by a rich air/fuel ratio and

-High fuel pressure due to bad fuel pressure regulator or other reason.
-Leaking injectors.
-EVAP system issues.
-Fuel in the engine oil. How is the engine oil?
-Plugged PCV valve.
-02/AF sensor issues, bad coolant temp sensor for computer, etc causing the computer to operate at rich mixture.
-Clogged air cleaner (but would need to be really clogged).

If my car might take it to auto shop having their own emissions tester and let them fix what is required to get the emissions under the states standards.

Alternatively assuming the car passed the states emissions test the last time it was required for license renewal indicating no major issues would:

Check air cleaner condition.

Determine when the spark plugs were last changed or just change them along with cap and rotor (if the engine has these).

Check PCV for sticking closed.

Put some injector cleaner in the tank.

Make sure the engine is operating at normal temperatures. Is the temp gauge reading normal.

Get all of the fuel out of the tank by draining, siphoning, etc then burning as much old fuel in the tank as possible via the engine then fill the tank completely full of fresh fuel. Alternatively take a long trip to burn all the fuel in the tank.

With tank full of new fuel operate the engine on the hwy for 100 miles at speed.

Make sure the car is fully warmed up before having it tested. If having to wait at the station long don't idle the engine excessively.

If you decide to go the 4L of methyl hydrate and fail the test before parking the car suggest you drive until the fuel is used up. If possible find a station that sells non-ethanol fuel then get a few gallons and add a fuel stabilizer. If your stuck with ethanol the opinions are to leave the tank full to keep water condensation inside the tank to a minimum down after one year the fuel will be bad one way or the other.

 

Thanks for that Toyomoho. Pretty informative. The fuel that's in my car is new. I had only about quarter tank when it sat for a year. I burned most of that driving my car to mechanic. I only put in another quarter tank to get to my first emissions test (which I failed). I was recommended to use CRC in a full tank of gas, drive it on the highway till tank was almost empty, refill and test again. So I filled my car, put CRC in it. Tested again a few days later and failed. But as mentioned it did go down from 1.17 to 0.58. So I was still off by 0.28 on the CO reading. That's when my mechanic friend said to put 3L of methyl hydrate in half tank, drive for an hour on the highway, refill tank, then test right away. He's recommended this before to others who were not that far from their limit on emissions readings. And it was enough to get them down to at least what their limit should be.

 

Worth a try but make sure you do the hwy driving.

Also check plugs, cap and rotor.

If the car sat for a year check air cleaner. It has happened mice will built a nest, etc.