A Mystique Mystery, now solved!

[Madman]

My mother called me the other day and told me she was having problems with her car, a 2000 Mercury Mistake...uh, I mean Mystique.  It has the 2.0 litre engine/four speed auto combo.  She said the car was shaking violently and the engine revs seemed to be surging up and down.  So I drove to her house and took her car for a spin.  

I started the car and the first thing I noticed was the "Check Engine" light was on.  I asked her how long this light has been on and she answered "A few months".    Apart from the light, everything seemed to be working well.  I decided to take the car for a drive to see if I could replicate the symptoms she was experiencing.  At first, everything seemed perfectly normal.  Then, about 10-15 minutes into the drive, the engine started losing power and acted like it wanted to stall.  I floored the accelerator and the car started bucking back and forth and I heard a series of popping noises from the rear of the car which I assumed was a backfiring exhaust.  The tacho needle was swinging up and down, even though I had my right foot nailed to the floor.

Believing it to be a fuel related issue, I asked her when and where she last filled up the tank.  I discovered she's been buying cheapo gasoline at Kroger.  Ah-ha, I thought.  Could this cheap swill be the cause of the problem?  Clogged injectors, maybe?  So I bought a couple of bottles of STP fuel injector cleaner and splashed in some Exxon premium gas.  After a while, the engine seemed to smooth out a bit but the bucking bronco party trick still rears it ugly head on occasions, usually under wide open throttle conditions and sometimes when cruising on the highway.

Oh, I also had that Check Engine light looked at.  I had Auto Zone plug in their code reader and it came up with a code "420".  420 supposedly means a catalytic converter failure which can also be due to an engine misfire, a large vacuum leak or oil leakage into the exhaust.  She's not losing any oil, so I can rule out that last one.  Am I really looking at replacing the catalytic converter?  I've never had one fail on any of my cars, so I find this very unusual.  Is there something else I'm missing?

I reset the Check Engine light and have been driving the Mystique for the past couple of days now.  (I loaned my mother the Volvo 240 whilst I try to determine what to do about her car.)  The light has not come back on despite a few intermittent episodes of bucking bronco syndrome behind the wheel of the Mistake...uh, I mean Mystique.

So, what do I have going on here, exactly?  I hate to have to bite the bullet and take to the dealer, but I may have no choice.  I want to get her off my case about this damn car.   More importantly, I WANT MY VOLVO BACK!!!  I would greatly appreciate any suggestions from those of you who are of the mechanically inclined persuasion.  I desperately need to get this mysterious Mystake fixed and back to my mother so that I may once again be able to enjoy the splendid bliss of driving a Volvo!  


Thanks in advance,
Madman of the People

[Rupert]

The fuel injector cleaner helped? How's the fuel filter? Fuel pump? Maybe the injectors are still fuckered up. Those are the places I'd start...

[giant_mtb]

Perhaps the bad gas fouled a spark plug or two.

[2o6]

I thought you liked the Mystique/Contour.

[JWC]

I thought it would have been a cat at first, but clearing the MIL wouldn't fix it.   I don't have access to Ford any longer, but I  seem to remember that these models had wiring harness problems.  The main engine harness insulation would dry rot and bare wires would touch each other and cause all sorts of weird and intermittent problems.

[SVT_Power]

P0420 is a precat O2 sensor CEL Bank 1 I think. But the contour/mystique cars like to throw a lot of O2 codes which don't necessarily mean the O2 has to be replaced. The contour board I'm on is down at the moment but give it a day and I'll have an answer for ya.

[SVT_Power]

Oh and don't worry a cat failure (even with the code saying so) is extremely rare on these cars although the car thinks otherwise 

[Secret Chimp]

Any MIL pointing to the cat can also be pointing to a bad oxygen sensor. Is the bumper sooty?

[mzziaz]

It could be a clogged cat.

[S204STi]

Inspect your spark plugs and wires.  While inspecting the electrodes for excessive wear or gapping issues take a good look at the porcelain insulator for anything resembling a crack or a dark grey line through it.  If you find any such condition you must also replace the wires.

FWIW the 2.0L SOHC "SPI" motor which was in our old Focus had its plugs replaced at about 90k mi and they were pretty much wiped out by that point.  Also, if you need plugs get the Ford Motorcraft plugs and wires only.  They are actually fairly inexpensive, usually less so than the aftermarket suppliers, and guaranteed to work right with your engine.

As for the P0420, if the car was driven with a hard misfire like that for so long I'm willing to bet the monolith is either partially melted or plugged.  Repair the cause of the misfire first and then drive it normally for a while.  If the code comes back, you've got an issue.  If not, then don't worry about it.

[Madman]

The fuel injector cleaner helped? How's the fuel filter? Fuel pump? Maybe the injectors are still fuckered up. Those are the places I'd start...

I'm beginning to wonder if the fuel injector cleaner really did help.  The problem is intermittent, so it's really difficult to say.  The fuel pump was replaced a few years ago but I have no idea how old the filter is.

Perhaps the bad gas fouled a spark plug or two.

It starts up straight away and idles smoothly, so I doubt there's any plug fouling.  I could always pull a plug and check it.

I thought you liked the Mystique/Contour.

I do, when it's not shaking me like a mechanical bull!  I've never driven this car any great distance before, so I'm starting to notice little things that really annoy me.  The headlights don't automatically turn themselves off when you switch off the engine, for example.  Why?  Almost every car I've ever owned had auto-off headlights, so I thought all car had them these days.  Okay, I admit that's really not a big deal.  But I do find having to remember to switch off the lights at night somewhat irritating.  Then there's no release button on the trunk lid.  You have to either use the key or pull a little lever on the floor next to the driver's seat.  Once again, just a minor irritant which I'm not used to.  But there's no excuse for the lack of a lock on the glove box door!  So where do I secure my wallet, camera, phone and radar detector?  They couldn't spend 50 cents putting a lock on the door?  Really?  DAMN YOU, FORD!!!  Oh, and there's also an aggravating squeek from somewhere inside the passenger seat when there's nobody sitting in it.  There is no such thing as squeeks in Volvoland, so I'm finding this hard to deal with!  Maybe I'm just spoiled?

Any MIL pointing to the cat can also be pointing to a bad oxygen sensor. Is the bumper sooty?

There's no soot on the bumper, but it's been raining since yesterday so it may have all washed off (if there was any).  The more I think about it, the more it sounds like a bad O2 sensor.  But which one?  I replaced the one on the intake side about a year ago so I'm guessing it has to be either the one on the exhaust manifold or the one behind the cat.



Thanks for the input, guys!

Madman of the People

[ifcar]

I do, when it's not shaking me like a mechanical bull!  I've never driven this car any great distance before, so I'm starting to notice little things that really annoy me.  The headlights don't automatically turn themselves off when you switch off the engine, for example.  Why?  Almost every car I've ever owned had auto-off headlights, so I thought all car had them these days.  Okay, I admit that's really not a big deal.  But I do find having to remember to switch off the lights at night somewhat irritating.  Then there's no release button on the trunk lid.  You have to either use the key or pull a little lever on the floor next to the driver's seat.  Once again, just a minor irritant which I'm not used to.  But there's no excuse for the lack of a lock on the glove box door!  So where do I secure my wallet, camera, phone and radar detector?  They couldn't spend 50 cents putting a lock on the door?  Really?  DAMN YOU, FORD!!!  Oh, and there's also an aggravating squeek from somewhere inside the passenger seat when there's nobody sitting in it.  There is no such thing as squeeks in Volvoland, so I'm finding this hard to deal with!  Maybe I'm just spoiled?

Few of those features are all that common, a handle on sedan trunks especially. (Most new cars do, however, have a keyfob with a trunk release button.) The only current cars I know of that have one are the Hyundai Azera and Genesis sedan (but not coupe.)

Even my Focus hatchback doesn't have a handle.

[CALL_911]

Few of those features are all that common, a handle on sedan trunks especially. (Most new cars do, however, have a keyfob with a trunk release button.) The only current cars I know of that have one are the Hyundai Azera and Genesis sedan (but not coupe.)

Even my Focus hatchback doesn't have a handle.

Just to be clear, when you say a handle on sedan trunks, you mean something ON the trunk by which the trunk can be opened with?

Many German/European cars have them. Our A4 and 5er have them, as does the TSX. I think the 3er has one too, but I could be wrong.

[Madman]

Just to be clear, when you say a handle on sedan trunks, you mean something ON the trunk by which the trunk can be opened with?

Many German/European cars have them. Our A4 and 5er have them, as does the TSX. I think the 3er has one too, but I could be wrong.

I was talking about the little button on my Volvos (and lacking on my mother's Mytique) which opens the trunk when the car is unlocked.  Both my old Peugeots had a release button, too.  And my old Merkur XR4Ti.  Hell, even my old 1979 VW Rabbit had a release button on the hatch!

I'm also becoming a bit annoyed at how you can't lock all four doors and the trunk just by using the key in the driver's door.  You have to press the power lock button inside the door and make sure you don't lock the keys inside.  How does anyone get away with such poorly thought-out design in this day and age?  With my Volvos, Peugeots, etc, it is impossible to lock your keys inside the car because you HAVE to use the key in the outside door lock to lock the car.  Grrrrrrrrr!!!


Cheers,
Madman of the People

[2o6]

I was talking about the little button on my Volvos (and lacking on my mother's Mytique) which opens the trunk when the car is unlocked.  Both my old Peugeots had a release button, too.  And my old Merkur XR4Ti.  Hell, even my old 1979 VW Rabbit had a release button on the hatch!

I'm also becoming a bit annoyed at how you can't lock all four doors and the trunk just by using the key in the driver's door.  You have to press the power lock button inside the door and make sure you don't lock the keys inside.  How does anyone get away with such poorly thought-out design in this day and age?  With my Volvos, Peugeots, etc, it is impossible to lock your keys inside the car because you HAVE to use the key in the outside door lock to lock the car.  Grrrrrrrrr!!!


Cheers,
Madman of the People

Almost all older Japanese, American, and Non Volvo cars do that. I don't see the problem.

[Madman]

Getting back on topic, if I am looking at replacing an O2 sensor, How can I tell if it's the one on the exhaust manifold or the one behind the cat?  Are these sensors a PITA to get to?


Cheers,
Madman of the People

[S204STi]

O2 sensors don't cause misfires, so you can forget about that.

[VTEC_Inside]

I was going to suggest plug wires/plugs, but R-inge beat me to it.

[Madman]

O2 sensors don't cause misfires, so you can forget about that.

It isn't a misfire.  I'm not really sure how to describe it.  I'm looking at the printout from Auto Zone again and I've noticed the bit where it says "Catalyst efficiency low- bank 1"  This leads me to think it's probably the O2 sensor behind the cat.  The CEL still hasn't come back on but I'm wondering if I should just go ahead and replace the O2 sensor behind the cat anyway.

Cheers,
Madman of the People

[S204STi]

It isn't a misfire.  I'm not really sure how to describe it.  I'm looking at the printout from Auto Zone again and I've noticed the bit where it says "Catalyst efficiency low- bank 1"  This leads me to think it's probably the O2 sensor behind the cat.  The CEL still hasn't come back on but I'm wondering if I should just go ahead and replace the O2 sensor behind the cat anyway.

Cheers,
Madman of the People

The engine is running rough, shaking, surging, etc. according to your first post, which is typical of a misfire. The catalyst efficiency code is most likely a result of damage, cats typically will fail if exposed to a hard misfire for many miles.  It is possible that the o2 sensor is bad, but the car won't run the catalyst monitor if it detects a faulty o2 sensor.  I'd repair the cause of the rough running first, which is not the O2 sensor.  You can still replace it if you want to make sure the cat is actually toast, but if an O2 sensor is bad, or it has codes such as the catalyst efficiency code, the car will automatically run in open loop which completely ignores O2 sensor readings.  That's why I'm telling you to ignore the O2 sensor as a possible cause of your violent shaking, surging, etc.

[SVT_Power]

http://contour.org/ceg-vb/search.php?searchid=1772202

[Madman]

Screw it.  I've taken the damn thing to the dealer.  Let them figure it out!


Cheers,
Madman of the People

[Madman]

Heard back from the dealer earlier today.  They say it needs a valve cover gasket because oil is leaking onto the spark plugs, which also means new plugs.  They also say it needs a mass air flow sensor and the range sensor for the transmission.  Evidently, the range sensor (This is what Ford calls it.  From what I gather, it's some sort of glorified speed sensor.) is located on top of the transmission.  I got a diagram of the transmission housing and it looks like it should be easy to reach.  Any of you Ford guys out there have any idea how difficult it is to access?

Here's the kicker: they want nearly $1,200.00 (plus tax) to fix these items!  Gulp!  Err, no thanks!  I'm going the DIY route.  I've already found a used MAF for $50.00 and the range sensor ($81.00) is, unfortunately, a dealer-only item.  Valve cover gasket and plugs cost peanuts.

And they wonder why nobody wants to take their car to the dealer after the warranty runs out!?!  And before you ask, the only reason we took it there is because it's where my mother has been getting it serviced.  She believes the dealer always knows best.

They certainly know how to charge customers and arm and a leg, that's for sure!


Cheers,
Madman of the People

[S204STi]

Ford parts are cheaper than the aftermarket.  You only pay extra for labor over the little guys, and even then it's a matter of $20 per hour if that.  Meaning that a lot of the time dealer prices are competitive with the independent shops.  Add to that factory training, tools, and service information and tech support and overall their problem solving and repairs are superior.

[the Teuton]

If dealer service centers were really the huge ripoffs we make them out to be, no one would take their cars there.

They're a little more expensive, but you're also paying a bit for the name there.

[Rupert]

Dealers are often a lot more professional, too. That's worth it sometimes.

[giant_mtb]

I'd trust a dealer over the Joe Shmoe mechy down the street with the run-down shop that has his 11 year old kid smoking cigarettes and working for him.



Not that there aren't independent mechanics that are actually good, but...

[VTEC_Inside]

Heard back from the dealer earlier today.  They say it needs a valve cover gasket because oil is leaking onto the spark plugs, which also means new plugs.  They also say it needs a mass air flow sensor and the range sensor for the transmission.  Evidently, the range sensor (This is what Ford calls it.  From what I gather, it's some sort of glorified speed sensor.) is located on top of the transmission.  I got a diagram of the transmission housing and it looks like it should be easy to reach.  Any of you Ford guys out there have any idea how difficult it is to access?

Here's the kicker: they want nearly $1,200.00 (plus tax) to fix these items!  Gulp!  Err, no thanks!  I'm going the DIY route.  I've already found a used MAF for $50.00 and the range sensor ($81.00) is, unfortunately, a dealer-only item.  Valve cover gasket and plugs cost peanuts.

And they wonder why nobody wants to take their car to the dealer after the warranty runs out!?!  And before you ask, the only reason we took it there is because it's where my mother has been getting it serviced.  She believes the dealer always knows best.

They certainly know how to charge customers and arm and a leg, that's for sure!


Cheers,
Madman of the People

The "range sensor" just lets the ECU know which gear is selected.

I'm puzzled as to the recommendation to replace it if you haven't had any strange transmission issues, ie unwarranted shifting....

Don't forget new plug well seals if that engine has them.

[Madman]

Got the car back from the dealer after telling them we weren't interested in having them do the work.  I looked over the written quote of all the stuff they wanted to replace and determined most of it was bullshit!  The valve cover gasket was not leaking and the plugs and wires were not soaked in oil as they claimed.  They also wanted to replace the air filter despite the fact that it already has a brand new one!

I seriously doubted it needed a mass air flow sensor, either.  It seemed the jerkiness and the surging were down to the transmission range sensor forcing the car to downshift in and out of passing gear when not needed.  So I bought the range sensor (at another Ford dealer) and replaced it myself.  After taking the car on an extensive shakedown drive, all was well.

Those THIEVING BASTARDS wanted to charge her $1,200.00 when all she needed was an $81.00 part that literally took me all of five minutes to change!!!

I don't know if CarSpin has a "Name and Shame" policy when it comes to outing crooked dealers and repair shops, but I would love nothing more than to drag this dealer's stealer's name through the mud for trying to rip-off a 67-year-old woman who knows very little about cars!

Needless to say, she'll NEVER be visiting these con-artists ever again!!!!!!!!!!  


Cheers,
Madman of the People

[giant_mtb]

Perhaps you should tell them about your dissatisfaction.  Write a letter, mention the name of the tech, and explain your frustration.  If management is good, they'll probably give the guy a word or two.

Or not...