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Engine light came back on after getting it fixed

Maintenance/Repairs
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#1

Alright, I drive a 2003 Mitsubishi Eclipse with only 75000 miles on it. I was driving home from work one day and the engine light came on so i took it to a place called breaks plus to get a diagnosis on the light. I was never given an exact code but as far as I know their were multiple piston misfires going on. And I remember him telling me there was oil leaking out of an intake valve (in case it’s not clear I know nothing about cars). Anyway here’s a list of things thats on the recept they gave me if that’s of any use.
oil change:
Lube oil and filter
Oil filter
5w30 Eco ultra syn blend oil bulk
Air filter
Fuel induction service;
2 part fuel injection/induction kit
Tune up;
Replaced spark plugs
Spk plug-iridium IX 1 EA NGK
valve cover gasket;
Valve cvr gasket set 1 EA FLPR
Anyway all those things that they fixed/replaced were supposed to fix the engine light but when I was driving home from the shop it came back on (it was off when I started the car initially)

My questions are:

  1. Is common to have an engine light come back on after getting it fixed?
  2. Is it possible the light will turn off after I drive it a few more miles?
  3. I work tonight, Is it even safe (for the car) to drive (about 35 miles total there and back)? (I didn’t notice any loud noises/metal clanking or anything like that/was running pretty smoothly.)
    4.Any other advice would be greatly appreciated
    UPDATE
    Just turned on my car to go to work and it’s idling funny. It goes from a low pitched “hum” sound to a high pitched “hum” sound back and forth. It’s also leaking fluid. It wasn’t doing that before I brought it in. I agree, I don’t think these guys have a clue what they’re doing.
    UPDATE 2
    Called the shop manager this morning after work, explained the issues I was having with it after picking it up from the shop yesterday. He emmidiatley sent two guys out to my house to come look at it. They determined it was safe to drive it back to their shop. About 3 hours later they called me back and fixed the new problems I was having,Apparently they accidentally cut a hose while repairing it yesterday and didn’t notice which is what was causing the weird idling hums I was getting as well as the leakage. I’m sitting in my car right now as I type this, listening to the engine. Gonna take it for a test drive And make sure everything sounds okay.
#2

Not if it is fixed properly. It is very obvious that the shop never test drove the car after they “fixed” everything, but simply reset the error code and sent you on your way. To better help you, we really need the error code. Stop by at Autozone or Advance Auto parts and ask them to read the code for you and let us know. They will do it for free, in most places.

Edit: [quote=“Ryderkgamer, post:1, topic:105436”]
a place called breaks plus
[/quote]
I hope the place is actually called “Brakes Plus”, but maybe they deserve the name you mentioned. A brake place maybe great for brakes, but I would be reluctant to let them do any work other than that. Very likely they do not have the experience nor the equipment and tools to properly diagnose a problem or fix it.

#3

As long as the Check Engine light isn’t flashing, the vehicle can be driven.

As far as the Check Engine light coming back on, the computer needs to be scanned again for any new codes.

Tester

#4

I don’t know about that…

The son works for a Good Year/Gemini service center.

With Good Year on the sign, you would think all they know is tires.

But nope! They do it all.

Even a certified AC technician.

He does admit though, someone in the shop should take a welding class.

Since the shop got a nice new MIG welder.

Tester

#5

  1. Is common to have an engine light come back on after getting it fixed?
    That’s a common complaint we get here. You are definitely not alone.

  2. Is it possible the light will turn off after I drive it a few more miles?
    Anything’s possible, but unlikely it will turn off by itself if there’s still a misfire.

4.Any other advice would be greatly appreciated

A “misfire” means the engine computer didn’t notice the crankshaft accelerating like it should immediately after the spark plug firing. The way it works, the spark plug fires, that sets off an explosion in the cylinder above the piston, which causes a turning force on the crankshaft. Somehow all that’s not happening for some reason. Everything that was done is a reasonable thing to do. Certainly bringing all the routine maintenance suggested in the owner’s manual up to date is a good thing, and often is a good place to start with a problem like this. But I wouldn’t expect that set of stuff to fix a misfire with any degree of certainty.

Suggest to break the process down. All these things have to all work for the cylinder to fire properly

  • Good healthy high voltage spark
  • At the right time
  • Correct amount of fuel and air in the cylinder
  • Good cylinder compression
  • Exhaust gasses exit the engine without interference or obstruction

So the shop has to go through each of those points one at a time. First off, they’ll read all the diagnostic codes. If the problem seems to be on certain cylinders only, they usually start with the spark. They’ll swap ignition parts like spark plugs and coils between cylinders to see if the problem follows the swap or not. If the problem seems to be on all the cylinders, they’ll do a fuel pressure test, and possibly other fuel injector system tests. Then they may check the exhaust system cat to see if it is blocked. They might do a tailpipe gas analysis. And they’d probably do a compression test.

I think the problem you may be having is the techs working on the problem don’t have the proper experience. It seems like they are engaging in some guessing. Suggest to ask your friends, relatives, fellow church goers, fellow bar hoppers, everybody you know, ask them who they use to fix their cars From that list chose an independent shop that specializes in Mitsubishi or at least Asian cars.

1 Like
#6

What kind of fluid is it leaking? Water, oil, transmission fluid…? I would not suggest you drive the car until the fluid leak is resolved.

#7

Not sure. I didn’t drive it to work (yay uber!). But I’ll have to take it back to the shop so they can fix what they screwed up which is about 2 miles from my house.

#9

I once gave a ride to a co-worker whose car was at a chain brake shop. The shop was probably a former tire shop with lots of bays. While I waited to see if the co-workers car was finished, (It wasn’t) I saw a brake “mechanic” removing the rear drum brake shoes and hardware. His method was to pry under the shoes with a large screw driver while he turned his head. Pieces flew for 8 or 10 feet.
I can imagine them telling each customer, “All the hardware was shot, and we replaced everyting.” Of course all of the parts and shoes would be the most cost effective Chinese pieces. I asked how he chose this shop. It was because of a coupon. Yes his new brakes were noisy.

#10

And that’s how we know they’re scam artists who won’t be fixing your car. You need to take it to a real mechanic - an independent one that’s not part of a chain and that gets good reviews.

2 Likes
#11

I would not suggest to drive the car without first checking all fluids, oil, transmission and water. Even 2 miles for a car without oil can be a death sentence for the engine. At a minimum check and top off before you take it back.

Actually, I would be reluctant to take it back to that shop.

#12

He’d better. There are serious safety issues involved with welding. Serious irreversible eye damage can result if the proper safety precautions aren’t observed.

As regards your problem, I agree with everyone else. That “shop” (I use the term loosely) performed a thorough wallet cleaning apparently without ever diagnosing the cause of your check engine light. One major clue to me is that they gave you no fault code, which is generally written on the shop order. A second is that they changed the valvecover gasket that would not trigger a fault code.

Shadow gave you what I consider excellent advice.
Sincere best.

#13

Hmmmm?

I wonder if they stood around wondering why they got an Auto Darkening Welding Helmet!

Pleeeeeze!

Tester

#14

If I not mistaken, there are a lot of engine designs where a leaking valve cover can result in oil in the spark plug wells. You initial diagnosis was for multiple misfire issue. Anyone diagnosing that issue and finding a leaking valve cover would fix that issue so I wouldn’t dismiss that as superfluous unless more information comes to light. Certainly, leaking fuel injectors could also result in misfire issues so the cleaning operation wasn’t completely out of the question either. There are so many potential reasons for multiple misfires, perhaps they took some of the less expensive routes first hoping it would solve the problem. In fact, the light is again on but we don’t know why so that needs to be resolved by reading the codes again. But it’s not blinking so unlikely it is the same issue.

I just worked on a coworker’s car with a cylinder 6 misfire. Found the spark plug covered in oil. Likely to be VCG leak from intake. Cleaned plug and coil boot just to eliminate coil as the problem. Code has not reappeared in a week. However, lo and behold, a new code just popped up, unrelated to the prior issues. Stuff happens…

1 Like
#15

I don’t usually put much stock in TSBs while diagnosing older cars, but this one is low mileage. I see several different TSBs (Technical Service Bulletins), published by Mitsubishi for Mitsubishi technicians to help them diagnose and remedy 2003 Mitsubishi Eclipse models, that involve multi-cylinder misfires (as many as 9 bulletins that may/may not apply).

They range from re-flashing the engine’s computer to replacing the ignition coil boot (on 2.4L engines) with a revised boot, for misfire problems ranging from hesitations, cold start, hot soaked restarts, idling, and high speed misfires.

What conditions are present when it misfires? All the time, when engine is cold, restarted after driving, wet outside, idling, cruising?
CSA

Be sure and have this diagnosed by one who knows what they’re doing (and will access bulletins) or you’ll run out of money and patience trying to get it resolved.

#16

A point well made. More specifically, on overhead cam engines there’ll typically be a “spark plug tube” at the bottom of which mount the spark plugs. Such designs will have O-rings at the bottom of the tubes, and oil can seep past those. On my engine the O-rings are actually molded into the valvecover gasket per the below image.

113119D.jpg900×620 114 KB

While the oil can’t get to the tips of the plugs via the seepage past the O-rings, the oil seepage can cause the boots that go over the ends of the plugs to deteriorate prematurely and can develop high-resistance shorts between the spark plug center electrodes and the metal around it. The voltage spike is high enough to overcome the high resistance and misfires can develop.

However, since it had no effect on the OP’s problem, and there’s no indication that there was any diagnosis done, I assume it was unnecessary. A problem of that type can be either confirmed or ruled out by visually examining the ends of the COPs (or boots). A scope could also show it. I don’t see any indication that the shop in question did any diagnosis, just made some wild guesses.

You did, however, make a good point.

#17

How do you know that it didn’t? As i pointed out, the light could just as easily be caused by something entirely new. The OP pointed out they looked at it and said it was safe to drive. Not a likely recomendation if code is still showing multiple misfires. In fact in update 2 to the original post, the op says what was fixed second time and it’s clearly not the same issue.

1 Like
#18

I have to admit and call this excellent service. Most other places would have told you to bring the car in, towed, pushed or otherwise. Admitting to their mistake adds to their good service.

#19

Yes, I expect the cut hose created a vacuum leak and that’s almost certainly what was causing the new symptom, the idle rpm surging back and forth. As far as the fluid leak, lots of cars leak fluids a little, and the owner usually knows what fluid it is, and how much it is leaking by monitoring the level over time. Since this problem just started for you after a big repair, suggest to at least have your shop determine what it is that’s leaking and show you how to monitor the fluid level for that fluid until they repair the leak.

#20

post deleted by creator

#21

With cars this old it is sometimes impossible to remove the air intake tube without it cracking, the rubber becomes hard and the tube will crack when removing or installing it. A leaking air intake tube can cause the surging during idle that you experienced and trigger a fault that illuminates the check engine light.

I see no reason to doubt that the valve cover was leaking and that the gasket was replaced. On cars this old it is common to find oil leaking into the spark plug tubes during spark plug replacement, that is caused by leaking upper spark plug tube seals or a leaking valve cover gasket.