80's-90's ford wagon tech questions

Discussion in 'General Station Wagon Discussions' started by DUANE7626, Apr 7, 2010.

  1. DUANE7626

    DUANE7626 New Member

    Joined:
    Apr 1, 2010
    Messages:
    5
    Likes Received:
    1
    Trophy Points:
    0
    Location:
    brandon,fl
    Hey guys ! As me admiring you and you excessive knowledge of " the wagon":bowdown: I have a few tech questions for someone who may be familiar with the 1990 mercury colony park wagon. I have a miss tot he engine i cannot seem to get rid of , I have been told it was the EGR valve on the intake, or possibly the t.p.s.(throttle postion sensor) I have been workign on cars for a while , and have never heard of an egr valave giving a car a "miss" i have already changed the plugs, wires, dist cap, and rotor button, and as well checked all the vacuum lines , i was pondering the idea of doing away with all of the emissions equiptment, the smog pump, and the egr, to my understanding they make a egr block out plate, can you guys give me some input ? and by the way i got some pics of the ole lead sled up for ya hoopitie.jpeg
     
  2. tbirdsps

    tbirdsps New Member Charter Member

    Joined:
    May 26, 2006
    Messages:
    5,341
    Likes Received:
    6
    Trophy Points:
    0
    Location:
    Ridgecrest, Ca.
    The only way the EGR valve is causing a miss is a vacuum leak then you won't notice it above idle.

    Since the engine is computer controlled and fuel injected it would be a mistake you'd never forgive yourself for if you removed the emissions equipment. Everything is calibrated together. If someone told you EGR or intake manifold they are refering to vacuum leaks. You can spray some carb cleaner around those parts and if the idle smooths out there is a leak. When you inspect vacuum lines it's best to remove one at a time and really inspect closely. Small cracks are quite difficult to see on the car. Especially check the large vacuum line that supplies the brake booster and the one to the PCV valve. Check them all very closely.

    A low speed miss can be caused by various things, vacuum leak being the most common. Spark plug gap is very important. Trust the emissions label on the inside of the hood or radiator support and gap them per the label. Remember when you set the base timing you have to disconnect the "spout". It's a single wire that goes to the distributor. Not sure of the location on your engine. Otherwise the computer will drive the timing back to where it was originally. Again the emissions label will state what the base timing is supposed to be. Don't forget to reconnect the spout when you are done checking the timing.

    Oops, I should have mentioned to not disconnect the hard plastic vacuum lines. It will be very obvious if one of those is broken. Just look carefully at the rubber fittings. They get very fragile with age.
     
    Last edited: Apr 7, 2010
  3. the Rev

    the Rev senior junior Charter Member

    Joined:
    Aug 24, 2006
    Messages:
    9,321
    Likes Received:
    24
    Trophy Points:
    0
    Wagon Garage:
    3
    Location:
    BC,canada
    thats some very solid advise you just got from Tbird(y)

    the only thing i'll add is ...
    ..I have never had a injected 302/351 that didnt have a miss !!:yup:

    my 89 Lincoln...i gave up...:evilsmile:

    being a mechanic for 40 years...heres my advice...
    ...sometimes ya just gotta know when to say...Screw It,Drive It:biglaugh:

    (i know...not good advise...but it works for me:evilsmile:)
     
  4. DUANE7626

    DUANE7626 New Member

    Joined:
    Apr 1, 2010
    Messages:
    5
    Likes Received:
    1
    Trophy Points:
    0
    Location:
    brandon,fl
    Finally did it !

    I finally broke down and took the old sled to a local shop , he ran it through the old OBDI computer , said the same thing , it was egr , apprenlty the valve was openeing too soon and causing a vacuum leak , i umplugged it and car runs 100% better , the miss is very minimal at low rpm's now :banghead3:, i think i am just goignt o leave it go until i finish the exhuast and see if that helps .. just cant stand the hiss of all the little pin holes in the exhaust whistling as i go down the road .. thanks for the advise guuys!!:thumbs2:
     

Share This Page