Can someone help explain the car trouble I'm having.

Factual Questions
1

I was driving yesterday when the chack engine light came on. I took it to Pepboys today and they gave me a list of stuff that “needs” to be fixed. I was wondering if someone can tell me how important all the repairs are, how soon it needs to be fixed, and if I’m getting ripped off. The car is a 92’ Lexus es300, and the following things need to be fixed: (everything in parentheses is what I was told te common name of the part was, it could be wrong)

99972 02 Sensor Upstream (Oxygen Sensor) = 132.26
99972 Downstream 02 Sensor (oxygen Sensor) = 146.87
99972 V/C Gasket (Valve Cover Gasket)= 64.72
D706 Rotor BWD Ignition Rotor = 5.99
C762 Dist. Cap BWD Distributor Cap = 15.99
CH5603 Tailor Mag Cor Wires BWD = 71.99
1982 Replace Fuel Filter Pkg = 81.99
99972 Plenum Gasket = 95.75

With those parts that need to be replaced, an oil change, and new brakes, they are looking to charge me close to $1500. Does this seem right, and how urgent is the situation. Thanks in advance.

2

Warning, IANALexusMechanic. BUT…
If you are asking what caused your check engine light, you need to find out what code PepBoys pulled out of your car.
Actually, with a '92, you’re still running OBD I, so if you can find a list of engine codes on the internet, and find the correct diagnostic ports to jump (usually, they are under the hood, toward the firewall on the driver’s side, for Toyotas, at least), you can check the codes yourself. Bridge the d8iagnotic ports, like with a pair of needlenose pliers or a paperclip, and the check engine light should flash your trouble code at you. Then you will have a vague idea what you need to fix. My guess is it’s related to one of the O2 sensors, mut it could have been some sort of misfire signal.

Now, it may be that you need all those other things, too. But only a few (say one or both of the O2 sensors, or the cap/rotor) will be what is causing your CEL.

3

They are definitely trying to screw you.

Things like the plenum gasket, valve cover gasket or spark plug cables usually do not need replacement and even if they are in bad condition, it is highly unlikely that they are causing the “check engine” light to turn on.

4

1)99972 02 Sensor Upstream (Oxygen Sensor) = 132.26
Maybe.

2)99972 Downstream 02 Sensor (oxygen Sensor) = 146.87
Maybe. But not at the same time as #1 - it’s unlikely both will go at the same time.

3)99972 V/C Gasket (Valve Cover Gasket)= 64.72
Not unless you’re leaking lots of oil from the upper half of the engine.

4)D706 Rotor BWD Ignition Rotor = 5.99
5)C762 Dist. Cap BWD Distributor Cap = 15.99
6)CH5603 Tailor Mag Cor Wires BWD = 71.99
Nope. 6 Champion copper spark plugs in this side. Any test that would say the rotor, distributor cap, and plug wires are shot simultaneously just doesn’t have a programmed output saying “Sell this guy $10 worth of spark plugs”.

7)1982 Replace Fuel Filter Pkg = 81.99
Absolutely - if it hasn’t been changed in 30,000 miles it needs to be, as should the air filter. Nothing like a lack of fuel or air to make a car run like crap.

8)99972 Plenum Gasket = 95.75
It’s really rare that these go, especially at the same time as the valve cover gasket.

Change the plugs, fuel filter, and air filter, and then disconnect the negative battery cable to reset the check engine light. If it goes on again, take it to an actual mechanic…

5

Sounds to me like they were taking the shotgun approach to auto repair – replace all the parts that could be causing the problems. On cars with computers, a competent mechanic with an analyzer can probably make a much better guess than just by going with the error code.

You can always try the cheap things, like spark plugs and air filter first as often they need to be replaced anyways.

It sounds like you are getting some emission-related error code. We just had one on our car, and spark plugs and an air filter cleared the code when the computer ran that test cycle again. If those don’t fix it, you may consider taking it to a mechanic rather than throwing parts at it. There is a lot of data the computer can give you besides the trouble code, and a good mechanic can use this data to find the exact problem.

6

My neice’s husband works as a mechanic at a Pepboys service center and he is ASE certified, as are all the mechanics that work there. That’s probably as real as you can get.

The question really is, what do you want to do with your car? If you just want your check engine light out, you can do the piecemeal approach suggested by others and throw parts at it till the light goes out. If you want your car fixed so it performs as designed and at peak efficiency, do as suggested by the service center. A third approach would be to take the money it would take to fix the car and trade yours in on a newer car. I did the throw parts at the car approach last year with my wife’s car and ended up spending spending almost as much as the estimate given by the service center at a new car dealer. The extra I would have spent would have been well worth the expense considering the aggravation I went through getting the car fixed right.

7

I was talking about the 17-year-old salesman at the counter - I haven’t seen a Pep Boys with bays in the back and mechanics.

8

If the car is running acceptably(and you can ignore the light), none of these need to be fixed.

It’s likely that the trouble light is on because of a bad O2 sensor. When the O2 sensor goes bad, the car is unable to “read” the oxygen levels in the exhaust, so it doesn’t know whether the car is running too rich or too lean. Instead, it just kinda guesses. This can result in poorer performance, emissions and economy. In extreme cases it can result in further damage to the emissions control systems, specifically the catalytic converter.

It may be that the O2 sensor has gone bad because of a problem with the ignition system. A misfiring cylinder(s) due to bad spark plug, wire or distributor cap/rotor will foul the O2 sensor.

So, maybe the O2 sensor(s) are just worn out. If the ignition system is in good shape, replacing the O2 sensor(s) will fix your problem(trouble light). If it isn’t in such good shape, replacing the O2 sensor(s) will be a waste of money because they will quickly go bad again.

It is suspicious that they didn’t specify new spark plugs to go with all the other new ignition hardware. Plugs should be the first thing to change.

I suspect that the trouble code probably specifies which O2 sensor is bad. If they are truely both bad, your car probably isn’t running too well.

It’s possible that there’s nothing wrong with the ignition system at all, and all you have is a dirty air filter(and now bad O2 sensors).

If the fuel filter hasn’t been changed in the interval recommended by the manufacturer, by all means change it. If the valve cover gasket is leaking unacceptably, change that too. Or don’t. As long as you don’t mind the mess and keep enough oil in the car, it doesnt need to be changed. I’m not sure what the plenum gasket is, but if it is the intake plenum and is allowing fresh/unfiltered air into the intake tract, that’s bad(and could be a cause of all your other problems).

As for brakes, it should be pretty evident when they are worn out (bad grinding noises, no stopping, etc).

9

General rule of thumb – very general, there are certainly exceptions – if the “check engine” light comes on and there are no other symptoms, it’s not an urgent matter. That doesn’t mean it’s not important – sometimes it is, sometimes not – but the light in and of itself doesn’t mean something must be tended to right away.

Now, if the light is flashing, that’s a different matter – it could be doing further damage and should be checked ASAP. It’s not going overboard to pull over, shut the engine off, and wait 5 minutes before driving further.

Back to the OP. I would say that everything expressed so far has merit. It might reasonably need all, some, or none of what was recommended. We’re all guessing somewhat since we’ve seen neither the car nor the test results. That said, here’s my armchair evaluation:

02 Sensor Upstream (Oxygen Sensor), Downstream 02 Sensor (oxygen Sensor)
Hmmm. While it’s not impossible it needs both oxygen sensors, it’s not too likely. I’d be very reluctant to replace either of them, much less both, without having tested their operation. Just a code that mentions an oxygen sensor isn’t sufficient info to condemn one. Many “oxygen sensor” codes – e.g. “O2 sensor always rich” – don’t mean that the sensor isn’t working right, rather that the sensor is accurately responding to the root problem.

V/C Gasket (Valve Cover Gasket)
Hmmm. Why? It’s extremely unlikely this has anything to do with the “check engine” light.

Rotor BWD Ignition Rotor, Dist. Cap BWD Distributor Cap
Usually fairly easy to test, not an uncommon problem.

Tailor Mag Cor Wires BWD
Again, fairly easy to test and not an uncommon problem, but…what you’ve listed sounds like some fancy-schmancy “high performance” plug wires (Mag Cor?). That sends up a red flag to me, in terms of trusting those wires to work properly. I suggest high quality original-design type wires.

Replace Fuel Filter Pkg
Package? What the hell is a fuel filter package? Presumably this is for maintenance, which is fine – for maintenance. If this is to fix the “check engine” light problem, then all the other stuff isn’t needed for that reason.

Plenum Gasket
I’m away from my books now, so I can’t check this, but I suspect it’s because the plenum ( = intake plenum = upper intake manifold) has to be removed in order to replace the valve cover gaskets.

My impression is that most of these items are on the list because the employees at the shop are trained and encouraged to sell, sell, sell. That doesn’t mean they aren’t justifiable repairs to recommend, but it’s a sure bet that not all of them are related to the light coming on, and it’s somewhat questionable that any of them will acutally fix the situation. I’d be inclined to seek a second opinion from a reputable independent shop (not a chain operation).

10

And here’s one thing that really bothers me about chains – it seems common for them to give these laundry lists with no attempt to prioritize the items, to explain what’s urgent or not, or explain what directly relates to the customer complaint or not. As far as I’m concerned, if you don’t know why the things on the list are needed or at least beneficial, or don’t know which items are important and/or urgent, and which items are not, the shop has failed miserably to serve you. Good auto service is more than just twisting wrenches. The person is the customer, not the car, and the person deserves to get a reasonable explanation, that he finds understandable, of the service recommendations.

11

Forgive my ignorance here, but would a 92 Lexus even *have *a distibutor cap & rotor, instead of electronic ignition??

If it does have them, then the wiser folks here probably have good advice. If not, you’re being fed total BS, & I’d go find another mechanic.

12

My “service engine light” is ALWAYS on. I took my car to my local mechanic, he told me the light is on because I need a new oxygen sensor. My car starts, runs and gets decent gas mileage as it is. We don’t need no stinkin’ oxygen sensor. YMMV.