No power, rough idle

Discussion in 'General Motoring' started by Roy, Sep 19, 2006.

  1. Roy

    Roy Guest

    98 SL1, 165,000km
    I have rough idle down around 500-750RPM (it usually idles just over
    1000RPM). Very little power. When I floor it in neutral the RPM gauge goes
    to 4200 and pulses.
    Looking under the hood at lunch time and the PCV hose was cracked/split and
    flattened. I replaced the hose but that seemed to make it worse. I remember
    talk on here of cleaning the PCV vavle but the Haynes manual I have only
    says what it does, no mention of cleaning.
    My question is, what should I clean it with? compressed air, gasoline,
    methyl hydrate...? Or should I just get a new one?
    Does this sound like a dirty or defective PCV valve or should I continue to
    look for other causes?
    Any advice or suggestion will be greatly appreciated.

    Roy
     
    Roy, Sep 19, 2006
    #1
  2. Roy

    Doug Miller Guest

    Just get a new one -- it's only about five bucks, if that much. Hardly worth
    trying to clean out...
    My guess is an ignition problem of some sort. Check the plugs; I'll bet
    they're not all firing. And *that* could be due to a bad plug, a bad plug
    wire, or a failed electronic ignition module.

    Another thing to check: make sure the exhaust system isn't plugged. A
    stopped-up catalytic converter can cause similar symptoms.
     
    Doug Miller, Sep 19, 2006
    #2
  3. Roy

    Roy Guest

    Thanks, after doing a little more searching I found there wasn't anybody
    suggesting cleaning although here in Canada it's more like $15 for the part
    (still very affordable). If that doesn't do it I guess it's time to start
    pulling wires and plugs.
    I really hope it isn't the cat, it was replaced 3 years ago and I really
    don't want to buy a new one yet.
     
    Roy, Sep 20, 2006
    #3
  4. Roy

    Doug Miller Guest

    Wow. That's kinda high. You buying that at the Saturn dealer? The going price
    at auto parts stores around here (Indianapolis) is about US$3.50-4.00, which
    is still under CDN$5. Have you tried WalMart or Canadian Tire?
    Most auto parts stores can test the ignition module for you, too, and the test
    is usually free.
    If the cat is only 3 years old, it's not likely to be causing trouble.
     
    Doug Miller, Sep 20, 2006
    #4
  5. Roy

    Roy Guest

    I was going by prices from web sites and forums, it was actually $5.94 plus
    tax from the dealer. That was cheaper than the other parts stores which were
    around $7-8 but none of them had one in stock, not sure why they bother to
    give you a price if they don't have one.
    As for free testing, we don't have Autozone here (I keep seeing people refer
    to them for free testing) and it is very hard to get anybody to do anything
    to a car for less than $40 (even to check codes). After I try the new plug
    wires I may see if the Saturn dealer will test it for me after I've spent
    $100+ on parts there.
    I replaced the PCV valve and hose. I put in new spark plugs (figured they
    were due anyway and inexpensive). The plugs helped a little by getting rid
    of the rough idle but it still has the miss and a little hesitation when I
    give it some gas. I guess next is plug wires ($70, I priced them while I was
    at the dealer).

    Not sure what to do if the new wires don't do it but I guess I'll keep
    following the ignition system unless somebody has a better idea.
     
    Roy, Sep 20, 2006
    #5
  6. Roy

    Doug Miller Guest

    Seventy dollars??? Damn. I realize that's Canadian dollars, not US, but your
    dollar is a lot stronger against ours now than it was just a few years ago.
    Right now, CDN$70 is about US$62 -- and that's a *hell* of a high price for
    spark plug wires. Especially for a 4-cylinder engine.

    For comparison, I just bought a set for my Suburban at a local auto parts
    store last weekend -- and that's a V-8 engine, twice as many wires -- for
    US$25 (= CDN$28 and change).
     
    Doug Miller, Sep 21, 2006
    #6
  7. Roy

    Roy Guest

    $70 was the dealer price. I got a set today at Canadian Tire for $30+tax.
    About the same as you paid for your 8 wires. They didn't help any so I guess
    I'm either getting a new distributor or going to get the codes read,
    whichever is cheaper.
    One of the terminals on the dist was white with corrosion and the last one
    had a big pile of rust setting on it when I took the wire off. Been a log
    time since I've dealt with an ignition system but I've never seen rust on a
    distributor before. The terminal wasn't rusted, it just wiped off so the
    rust must have come from inside the wire end.
     
    Roy, Sep 21, 2006
    #7
  8. Roy

    BläBlä Guest

    Roy it sounds to me you went way to long without servicing your ignition
    system! The rust is from your spark plug wires connector. You have no
    "distributor", what you are looking at is a coil pack. Two coils each
    with two coil "towers". This system is known as a waste spark system.

    FYI a new set of wires doesnt mean a darn thing if you do not use an OHM
    meter to check the resistance of the wires. It seems no less than 50% of
    the wire sets I buy have at least one wire that is either out of spec or
    completely dead! A bad wire can make your car run like crap and WILL
    eventually kill your coils.

    The resistance of the wires on a S-series Saturn should be no greater
    than 12,000 OHMS (12k ohms). If you tug or bend your wires you can
    damage them so if in doubt check the resistance again. Buy some Silicon
    Greese (if none comes with the wire set) and apply it to the insides of
    the spark plug boots. This will prevent future corrosion and keep the
    boots from sticking. Wires should always be replaced at the same time as
    plugs or sooner if they are in poor shape.

    There are only 2 types of spark plugs I recommend. AC DELCO and Autolite
    both in "double platinum". Some say NGK but I have never ran across
    double platinum NGK's here. The double platinum plugs should last 80k
    miles. Non platinum plugs last 30k tops. (do NOT buy Bosch plugs at all)
    Also buy Anti Seize compound and apply a small dab to the spark plug
    threads and keep it away from the electrodes.


    Other advice
    -------------
    Clean your coil towers before attatching the new wires.

    Before removing your old spark plugs make sure there is no debris that
    will fall into the combustion chamber.

    If you find oil on your spark plug boots and in your spark plug wells
    (DOHC engine) you will need a new cam cover gasket set.

    See if your old wires have nicks or chafing. You can use "wire looms" to
    help prevent the new plug wires from chafing in those same places.

    The order of your engine from front to rear is
    1234
    The order of your coil towers from front to rear is
    4123
    Just match the numbers.

    Inspect your old plugs
    http://www.gnttype.org/techarea/engine/plugs.html
     
    BläBlä, Sep 22, 2006
    #8
  9. Roy

    BläBlä Guest

    Brake clean. Only replace it with the OEM if you do.
    The cat failure is a symptom of a greater problem. Was the problem ever
    corrected? Failure to keep the car tuned up is one way of taking out a
    cat. It could of also been an "Upsale".
     
    BläBlä, Sep 22, 2006
    #9
  10. Roy

    Roy Guest

    It was only $6 for a new one so I replaced it. Had to be from Saturn as no
    one else in town sold them.
    Cat was replaced under warranty so it wasn't an "upsale." Not sure why it
    failed but the dealer didn't seem too concerned and I'm sure they were
    looking as only the emission system was still under warranty.
     
    Roy, Sep 22, 2006
    #10
  11. Roy

    Bob Shuman Guest

    The key point in Bla's advice (lots of good stuff, but didn't want this to
    get lost since it is very important) here is to clean the corrosion off the
    ignition tower. This is most likely what is causing your rough idle. Also
    make sure all grounds cables are clean and tight as well.

    Good luck.

    Bob
     
    Bob Shuman, Sep 23, 2006
    #11
  12. Roy

    Roy Guest

    Got the miss fixed. It was the ignition coil. Found what was probably the
    cause of the failure or at least contributed to it. Somebody worked on it
    before I bought it and snapped off the bottom bolt on the passenger side. IT
    is in there fairly tight using just the upper bolt but does anybody know of
    an easy way to get the broken bolt out so I can get a new bolt in to secure
    it properly.
     
    Roy, Oct 24, 2006
    #12
  13. Roy

    NapalmHeart Guest

    broken screw extractor?

     
    NapalmHeart, Oct 27, 2006
    #13
  14. Roy

    Roy Guest

    Kind of a tight spot to get into with any kind of power tools. I was just
    hoping somebody had taken one out and knew a trick.
     
    Roy, Oct 28, 2006
    #14
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