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Going to the mechanic to make sure everything gets diagnosed?

I’m planning on going to the mechanic tomorrow so I ran a diagnostic test at the auto parts store. I’m going in because there is a stutter when the car starts and the engine light came on last night; these messages all came up on the diagnostic:

Suppression Sensor 1 Circuit (Service)
Random–Multiple Misfire Detected (MIL)
Cylinder 1 Misfire Detected
Cylinder 4 Misfire Detected
Cylinder 6 Misfire Detected
Evaporative Emission System Leak Detected (Gross Leak / No Flow)

I’m trying to figure out if that’s enough, or if there’s any other info I should gather before I go in. The place I’m going to charges $50 for a basic diagnosis of the problem, and then +$50 for every addition level they have to go up to investigate. I don’t know what they mean by levels, I’m just trying to keep the cost as low as possible.

First of all just let them do their job. Keep the print out from the parts house to compare with what they find. As for the next level have them explain what that means and if they will call before doing so. You can also ask if they waive any part of the diagnostic fee if they do the repair work.

Where do I get print outs from a parts house?

Should I tell them what the diagnostic tool said?

Any decent shop isn’t going to use the auto parts store diagnosis so that won’t save you any money on their diagnosis. Who would be willing to bet their reputation on someone else’s diagnostic printout? Not many.

I wouldn’t like the way the shop you went to described their process. It sounds too ambiguous. Most reputable shops will have a fee for initial diagnosis. From there they will formulate a repair plan and should be able to share details with you before commencing any work. At this point, you can ask questions and get a feel for how certain they are that the problem will get resolved.

"saturn vue "


I used a Bosch diagnostic at an auto parts store just to get an idea. But I went into the mechanic today and they fixed the spark plug, which solved the starting ‘stutter’ and the dashboard lights.

So you got a minor tune-up, sparkplugs only? If the emissions leak wasn’t fixed the check engine light will still come on.

I now have $4 left until payday, so it’s gonna have to wait ://

Keep us informed. May need a smoke test and a scanner that can put the solenoids of the Evap system through a test. Just part of diagnosis. ( probably already did a visual).

By your description the stuttering/misfire seems like an ignition system problem. Glad you got that fixed for short money. If that problem returns, try it with the fuel cap loosened, see if that has any effect. Don’t drive that way, dangerous, just as a test. Sometimes a problem with the evap system will form a vacuum in the gas tank, & prevent fuel from readily flowing from the tank to the engine. That can cause a misfire.

I’m guessing however you’ve got the misfire problem solved but you still have an evap system problem of some kind remaining. As long as it isn’t causing performance problems, or leaking fuel, then you have some time to save up for the fix. fyi, the car’s evap system is part of its emissions system to prevent air pollution, designed to prevent gas fumes from escaping into the air. It traps & holds on to them instead, and eventually burns them in the engine. For that to work the whole system has to be air tight, and yours apparently isn’t.

4 bucks! Ouch!
This can wait, no problem. This problem is very, very common and not an emergency. It could possibly correct itself.

This can be caused by a gas cap not fully sealing. Before I paid somebody to diagnose this, I’d spray some WD-40 or equivalent on the gas cap seal and sealing ring of the filler neck and retighten it. Some folks just purchase a new gas cap and try that.

You’ll need to drive for a while and see if the check engine light goes off (if it’s on).

However, the misfire problem you had fixed could not wait. Damage to the vehicle would be the result of putting that off. Good work! :slight_smile:

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