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Smoke test

Ok. I am new here. First time asking a question because I am so at a loss of where to go to get a “smoke test” for my '01Chevy Cavalier. Car runs great! has over 160K, but won’t pass inspection. There is a some sort of problem with a leak in a line or hose or something. And it will need a smoke test to determine where the problem is. My problem is I am woman who has been taken advantage of when it comes to having my car repaired that I would like to know what to expect in terms of cost. I know some are highter, some lower. But a ballpark would help. I am looking to buy a newer car in the spring. But right now I am driving with an expired inspection. My son already got a ticket driving my car. I am unsure of where to go for this. I live in Rochester, ny. My son’s friend normally works on my car and only charges me parts and I give him some for labor. So I have no clue what to expect or where to go. Any information would be appreciated. Thanks! Tricia111

I assume you’re failing inspection for an engine light being on and a fault code in the computer memory related to the Evaporative Emissions System? Could you find/tell us the specific fault code, like P0446 or something like that.

It sounds like you may have a vapor leak in your fuel system somewhere, and after testing various valves and switches for operation, we (mechanics) may have to test for a leak by injecting smoke into the fuel tank system and then inspecting closely for any smoke leaking out where it shouldn’t be–which would be anywhere. The problem could be as simple as a $12 gas cap to hundreds of dollars to remove the gas tank to repair a rotten seal or component.

As for the cost of the actual testing, it’s going to vary widely but around here a hundred bucks or so would be fair.

I’d think any well-equipped shop could do the test. Call around and see what it will cost you.

Tricia, if you have a check engine light on, take the vehicle to an autoparts store like AutoZone and ask them to read the codes for you. Get the actual code which will start with a P followed by four numbers. They will usually give you a cash register printout with the code and possible remedies, just post the code here and we will see if we can help.

If you are getting a MIL (check engine light on ) intermittently, and you notice that it tends to come on right after buying gas, then goes out in a couple of days, then you are probably overfilling your gas tank. Stop filling on the first click and eventually the problem will take care of itself.

If your son’s friend has a code reader, he could pull the code for you. If he doesn’t have one, you can get a simple code reader for about $50 and give it to him as a present for all the work he has done in the past.

I’m curious of the details behind your being taken advantage of. Many people think they’re being screwed over simply because they don’t like a price or cannot comprehend the mechanical principles behind a repair.

If someone feels a smoke test is needed then call the shop and price one; followed by telling the shop you want the test only, no repairs.

Thanks so much for suggestions. I actually have already gotten the print out from auto zone before I posted my question. That’s the reason I asked about what the average cost of a smoke test is. There were 3 different possibilities according to the print out. We already tried the gas cap and replaced the canister. Last was a leak. Which the print out didn’t specify. My son’s friend said I would need a smoke test to determine exactly where the leak was. Oh and I have been had over the years by being overcharged… which I found out later. And another time I was told my problem was 2 different things wrong. It turned out later that my problem only needed one thing replaced. The other was just a suggestion. Didn’t know that till way later when I looked up a code on the receipt. The suggested item, wasn’t necessary to fix the current problem I was having even though I was told differently. I remember at the time I was low on money and ended up not being able to pay my rent. We are going back a couple of decades ago so I can’t remember the details of what was going on with the car specifically. But believe me it is a common problem women have.

ps. I just reread the question I asked and realized that it wasn’t very clear. I just wanted to know what a smoke test would cost… ballpark… which asemaster did give me. At around $100. One place wanted to charge me $175. I’m shopping around. Thanks.

@Tricia111 if you’re not yet sure what the exact problem is, why have you already replaced the canister? That isn’t a cheap guess.
I suggest you take your car to a shop that has an evap/smoke machine, knows how to use it and knows how to diagnose and fix vehicles. Unfortunately, not all shops fall into all three categories.

This is a commonly done test by pro-mechanics and should prove no problem. A local independent shop is probably your best bet. The best way to choose a local shop is to ask friends, co-workers, fellow church goers, anyone you have a personal connection with, etc for a shop recommendation. The, when you arrive, the first thing to do is inform the shop owner who recommended you. This give you some leverage, as if you end up not satisfied, not only does the shop loose your business, but they will likely loose the recommender’s business too.

Will you car run any better by getting this “Smoke test”? No…Will it get better mileage? No…Will it last longer?..No…Will it perform better? No…And, most importantly, will the air quality of the State of New York be improved by you getting this test, spending hundreds of dollars on “repairs” that do nothing?? No…

If EVERYONE’S car had a fuel tank venting problem, MAYBE it MIGHT make a difference…But just your car and a few others like your car? I’m afraid they just don’t make any difference in air quality whether they pass an emissions test or not…And believe it or not, the “safety inspection” doesn’t make any difference in highway safety either…

Try this…Disconnect the negative battery cable for a minute or two. The CEL should go out…If it stays out for a day or two, go get another test…