Ford's 4.6L motor discussion.

bobc7bobc7 Member Posts: 3
edited March 2014 in Lincoln
Has anybody experienced "excess wear" on Ford's
4.6L motor? My 93 Lincoln TC has 126000 miles and
is starting to blow smoke after idling at a traffic
signal. Also is using a quart of oil in 1500
miles. Maintenance has been regular (LOF every 5000
miles). Dealer wants to install a new motor for
$3000. Any word from Ford? Any similar experiences?


  • guitarzanguitarzan OhioMember Posts: 864
    There is another topic where Expedition owners complained about lack of power in this engine. The Town Car, not sure how it compares in weight to an Expedition, but it is a large vehicle. It sounds like the vehicle has strained the motor too much throughout its life.

    You can have an independent mechanic install an engine from the scrapyard. Not sure if it is possible, but if it works, a 302 might be a good replacement choice.

    Community leader/Vans conference
  • ton7ton7 Member Posts: 1
    I had a 1994 Cougar with the 4.6L engine. I sold it with 93,000 miles on it. It had just start using about 1qt. of oil every 2000 miles or so. No smoke or drips. The car did not use any oil until around 90,000 miles.

    The car had an easy life. Driven by my wife. No racing and regular service.
  • bobc7bobc7 Member Posts: 3
    An independent shop owner checked the EGR valve and indicated that only "valve guide seals" should be replaced. The egr worked properly with no smoke. The compression is also good. Thus his recommendation to replace the valve guide seals. His price to do the job was $407. Once he gets air into the cylinder chamber the need for rings will also be determined.
    Any comments or suggestions?
  • dhoffdhoff Member Posts: 282
    The symptoms you describe do sound more like valve guide wear that piston ring wear. Considering that the vehicle had regular oil changes, I'd be really surprised if the piston rings and/or bore were worn.

    I don't know if his price for the work is good or not, but it doesn't sound that bad to me. This being an overhead cam engine with 2 banks of cylinders to work on, there's probably a lot of labor involved.

    If he does a compression leakdown test he will be able to tell if the cylinders are worn, but as I said I would be surprised if they were.

  • ottomanottoman Member Posts: 7
    I have a '92 C/V with the 4.6 engine and 104000 miles. About 95000 miles I noticed that it was starting to use oil between changes (3000 miles). It now is doing the same thing as "bobc7" town car is doing. If the car is idles for any period of time and then you drive off the smoke can be excessive. Otherwise the car still drives well, idles smooth and sounds quiet. It sounds like valve guide seals to me as well.
  • bobc7bobc7 Member Posts: 3
    The repair shop removed the valve covers and discovered a very clean (no sludge) engine. He said he expected "some" and this prompted him to stop work. The valve seals were as pliable as the replacements and thus the problem was deeper. I chose not to continue as the labor costs to remove the heads and see "if" the valves were the problem or "if" he had to continue into the block to check rings, would not be practical. The suggestion of a new motor was dismissed in light that the mileage and condition of the rest of the components (air, transmission, tires, etc.) were questionable. I am going to shop for a new car.
    Thanks for all your responses and happy motoring.
  • rea98drea98d Member Posts: 982
    My 95 T-Bird has the 4.6, and nearly 141,000 miles, and uses no oil, and no smoke. The car's original owner was an East Texas rancher's wife, (not the kind of person to be hot rodding), and all the regular service was done to the car. The only problem with the car is a faulty EGR, but after spending 220 bucks and seeing no results, and since driveability is not affected, I can live with the idiot light burning. While my bird is lighter than a Town Car, I was told getting another 140,000 out of that engine was not unusual if I took car of it.
  • georgeedgeorgeed Member Posts: 2
    My wife's 4.6 T-Bird (Bill Elliot tuned edition) is as solid as a rock with 116,800+ miles on it. It still does everything well, but she commutes 80 miles one way from the North Georgia mountains to Decatur (Atlanta), GA. She has had only brakes, tires, and a repalcement fan for the radiator cooling. Yet, for peace of mind, we bought a new 300M for the daily commute. We will sell the T-Bird only because she needs to feel the confidence of a newer car. We are impressed with a V-8 that gets 30 mpg on the highway while having the power to do whatever needs to be done with power. Anybody need a good used T-Bird. The 300M does not get 30 MPG! But does it drive nice.
  • lsattlelsattle Member Posts: 13
    When egr valves fail they just don't turn on idiot lights. My understanding (very weak) is that they will cause heads to run much hotter. It is weird, but the egr valve causes exhaust gases to get recycled thru the combustion chamber. But the engine runs cooler when they are working. I had an 84 Chrysler 2.2 litre. The egr was out for years and the car valve knocked a lot. I didn't know the thing was out. Eventually the head gasket went. Then I found out about egr valves.
  • rea98drea98d Member Posts: 982
    Yeah, and my cousin (ASE certified mechanic) says it has severe and negitave impact on drivability. I'm thinking its just an instrumentation problem. The mechanic I took it too unclogged some port on the intake manifold, but according to my cousin, that would not trigger a code to make the idiot light come on. I think my mechanic does not know a thing about computerized cars, because he did a great job of repairing my old 78 Grand Marquis. Ain't technology wonderful!
  • gjupingjupin Member Posts: 1
    My 1997 Ford F-150 (21,000 miles) with a 4.6L engine is experiencing engine knock on cold starts when the air temperature is below 50 degrees. The knock stops after about 10 to 15 seconds. Oil pressure appears to be normal. I'm using 5W-30 oil as recommended by Ford. I use this truck on weekends and on vacations. Its not unusual for the truck to sit for five-days without running. Considered switching to Mobil One because of the length of time the engine sits idle or Slick 50. I intend to speak to Ford about this problem at the first opportunity. Has anyone had experience with this problem and what are the recommended solutions? Thanks for your input.
  • moho2moho2 Member Posts: 2
    Sorry to hear that you have engine knock problem with your 4.6l engine. I would strongly recommend going to F150 online web site to look for answer to your problem, as I do remember seeing the same topic posted in one of the topics they have there. Great site with lots of great people, and useful information. Good luck!
  • weslwesl Member Posts: 53
    The 4.6 engine is durable, and many with any care most people will see at least 200,000 miles. However, many people have expressed concerns regarding piston knock and oil consumption at high miles. Piston knock upon start up is NORMAL, and nothing to worry about. It is part of the design of pistons and rings and nothing to do with the reliability of the engine. Ford is probably not acting on most complaints because there is no problem. I must remind everyone that I am referring to cold knock or piston slap on start up. If your engine is knocking constantly after warming than you do have a problem. As for oil consumption, the problem seems to be most pronounced in the earlier 4.6 engines. Valve guide oil seals are usually the problem, but I have heard that the 4.6 is also has excessive ring wear problems as well. Overall a very bullet proof engine, but every design is not without its faults. Hope this helps, Wes.
  • rea98drea98d Member Posts: 982
    95 Ford, 145,000 miles. I was driving home the other day (300 mile road trip), and when I put my foot on the brake, the oil pressure dropped to zero and the red "Check Guages" idiot light came on. Let my foot off the brake, and oil pressure instantly shot back up to normal. Total time without oil pressure: Less than a second. I decided I was running low on oil, stopped at a gas station and poured in another quart. Problem solved. Next day I added another quart, and checked the dipstick. No reading. Oil pressure is normal and steady, but she's still low on oil. Engine is making plenty of power, good gas mileage, and no bluish-white smoke, so I know she's not burning the oil. I'm pretty sure she has a leak, but she's not leaving a puddle of oil under the car either. Where is this oil going? Could it be that she only leaks when the oil is under pressure? How much $$$ will it cost to fix this problem?
  • bcollisonbcollison Member Posts: 24
    My T-bird had this knock on cold start-up as well. It was just the oil filter. The old Motorcraft filters didn't have a silicone anti-drainback valve, so the oil drained out. So I tried the purolater 1 filter and the knocking quit and hasn't done it since. Now Motorcraft filters have this silicone valve (Only on the FL820S filter!!) in it so I have used this filter and have had good luck too. It hasn't knocked once in years!! My advice is to look for this silicone valve. I know purolater 1 filters have this silicone valve. Good Luck
  • sgtvirasgtvira Member Posts: 2
    why is it that the only indication of oil consumption is when i've ideled for a while. if it was the guide wouldn't i be smoking all the time - and the longer i set there the worse the some is
  • sgtvirasgtvira Member Posts: 2
    why is it that the only indication of oil consumption is when i've ideled for a while. if it was the guide wouldn't i be smoking all the time - and the longer i set there the worse it is
  • kinleykinley Member Posts: 854
    Please check the neoprene seal around the oil pressure sending unit. If it is cracked, oil, under pressure, will ooze out and eventually drip on the pavement as you drive, yet your driveway is clean. Very economical repair job.
  • wilcoxwilcox Member Posts: 582
    Check to make sure you are putting the oil in the correct place. Check your radiator....
  • kinleykinley Member Posts: 854
    It's true, I once saw a person adding oil to the engine via the dip stick housing while wondering how the mechanics did it without spilling.
  • rea98drea98d Member Posts: 982
    No, I'm not putting it in the radiator. It goes in that box that says "Wiper fluid only" right?
    While I was using my T-Bird to jump start my mercury, I came one step closer to a solution, although I have yet to find the time or the $ to take it to a mechanic. Smoke started coming from somewhere behind the left cylinder bank after letting it run at about 2,000 rpm for a couple of minutes. Smoke smells like burnt oil, so now I'm thinking valve cover gasket or head gasket. So now I need to know how much replacing a head gasket on a 4.6l T-Bird can expect to set me back?
  • kinleykinley Member Posts: 854
    the seal around the oil pressure sending unit needs to be replaced. Not expensive compared to a gasket replacement.
  • rea98drea98d Member Posts: 982
    True, but I'm never that lucky :-)
  • btroybtroy Member Posts: 92
    Just for the fun of it, can you tell us where the oil pressure sending unit is located? It's not in my Haynes manual. I wanted to check mine because my oil pressure is suddenly reading lower and variable, when it has always been above half on the guage and steady as a rock.
  • kinleykinley Member Posts: 854
    near the oil filter and the oil pressure sensor. I hope this helps, btw, I found where my Haynes manual shows it on page 2B-3, however the manual is 5901l (2117) for Lincoln, 70-96. Good Luck to you and may the cost be minimal.
  • rea98drea98d Member Posts: 982
    I have a 78 Grand Marquis with a 400 cid V-8 engine. I had the heads rebuilt a couple of years ago, and now the bottom end needs it. But I am giving serious consideration to replacing the engine (and possibly the anemic FMX transmission) with a 4.6 litre, which is smaller, ligher, more powerful an burns less gas. What would be involved in a switch like this? Would the HVAC come from the old car, or the new engine? What about radiators, engine mounts, driveshfts and the like. If someone could steer me in the direction of some information I would be grateful.
  • btroybtroy Member Posts: 92
    rea98d, why bother with all that work? For the thousands of dollars and all the hassle that it would take, wouldn't you be better off shopping for a good deal on a '92-'94 Grand Marquis that already has a 4.6L in it? You would probably end up with better transportation and more money in your pocket doing that. Think of it as buying an engine and getting a newer car thrown in for free.

    I'm just thinking practically, but maybe you have an attachment to your car or consider it to be a restorable classic.
  • rea98drea98d Member Posts: 982
    I have an attachment to the car, plus I'm just another gearhead who wants an impossible technical challenge to keep me occupied. My history with the car: brought me home from hospital when I was born, first car I ever drove, first car I ever owned, first car I ever named, took me through high school and part of college. Plus I like the 78's style better than the 92-94's.
  • goober10goober10 Member Posts: 1
    Good News for 4.6L cold engine knock, Ford recently replaced my engine under warranty.
    (1998 F-150 w/24k) The knock in my engine did not suppress until the completly warmed up. The new motor is running good! Good Luck.
  • teeburdteeburd Member Posts: 4
    Just recently purchased a '96 T-Bird from a reputable dealer. Seems to be using about 1qt. per 2K miles. Car only has 36K on it! Can anyone tell me what the previous owner did to cause this?
  • vamovamo Member Posts: 2
    Read message #30. Your mistake was buying the bird. You will note that your oil pressure guage shows low oil pressure most times. I had the drop the pan & clean the filter. No more problems.
    PS. Your in for some tranny problems. Will feel like your driving over a wash board. Car was just over warranty. Fors wanted to do a tranny job at my expense.
    Mechanic pulled me over to side & told me to change fluid & make SURE they dump the torque conveter. They did job & I still had problem. They didn't dump the converter. Took it to Gease Monkey & they flushed the tranny. No more problems. All automatics hve the problem yet FORD will not use a recall. Got so disgusted with it I dumped it.
  • rea98drea98d Member Posts: 982
    Don't be dismayed by the horror stories. I have a 95 T-Bird, 4.6 engine, automatic with overdrive, and 149,000 miles. Only trouble I've had with this car has been the fact that she didn't get her 100,000 mile tuneup til last thursday, and the heater core blew out and had to be replaced. She leaks a little bit of oil, but considering her mileage, she's in great shape. (I think it's the left valve cover). Still gets 27 mpg highway, and the transmission's in great shape. Just keep a quart of oil in it between changes, and do all the preventive maintainence, and she should last you. I plan on getting at least 300,000 miles out of my Bird, barring any major wrecks.
  • teeburdteeburd Member Posts: 4
    By the way, the oil pressure guage doesn't read low at ANY time. The car is immaculate inside and out. Previous owner gave it a clean bill of health. And as far as your "I shouldn't have bought the car" advice, hindsight is 20/20. My previous Bird had over 140k on it with very little problems so I felt comfortable buying another.
  • tinker222tinker222 Member Posts: 1
    My 4.6 in a 2000 Expedition EB died at 410.6 miles. Started missing at 60 mph, then started to knock, before I could get it off the road the engine locked up. Ford said the processor failed and left one of the injectors open. The cylinder filled with full and broke the plug off. The engine was replaced along with the processor. Is there anything else that Ford should have done?
  • lindeman1lindeman1 Member Posts: 9
    I have noticed a lot of Crown Vics and Grand Marquis lately blowing blue smoke out the tailpipes, especially while accelerating from a stoplight. They appear to be older models and are obviously equipped with 4.6L engines. I determined that these engines obviously had some kind of a problem when I first noticed it. Hopefully this is a defect in older high-mileage 4.6's and Ford has corrected it in newer models. I wouldn't own one though.
  • nsquarednsquared Member Posts: 2
    I have a problem I'd like your input on. I have a 4.6L y2k mustang. My problem is...the car idles at 3,000 - 3,500 rpm when I come to traffic stops. I'll just stop at a red light and the tachometer will sowly start rising (never beyond 3,500 rpm) and the engine compartment will start roaring. It's an intermittent problem, occurring about 5x a week, but not predictable. The car is possessed! Ford has replaced the idle air control motor /valve and the on-board computer among other things. Have any of you heard of such a thing?

    At this point Ford has agreed to replace the vehicle altogether and consider it a lemon. I took delivery in Oct 1999 and it has 2,300 miles. Is this a common problem in their cars? Should I just get something else? Help?
  • rea98drea98d Member Posts: 982
    I haven't had any problem like that with my 95 T-Bird. At least Ford agreed to replace it. I'm assuming they didn't give you a hard time about declaring it a lemon, otherwise, we'd probably have heard about it. FWIW RE#35, I beleive 95 was the first year of the 4.6, and mine has 151,000 on it, and other than a leaky valve cover, the engine runs great, and I get 27 mpg on the highway regularly.
  • nsquarednsquared Member Posts: 2
    I figure Ford makes so many vehicles, one is bound to be defective...and I just happened to get it. It was definitely a pain, but that's life. Ford was pretty agreeable, there was really no way around replacing the car. Hopefully the new car will be a charm. Glad you're enjoying your 95 T-bird. Hopefully my mustang and I will lead a similarly healthy life.
  • btroybtroy Member Posts: 92
    My previous car had a recommended maintenance interval for replacing the oxygen sensor. I noticed my 96 Crown Vic with the 4.6L engine service schedule doesn't mention replacing it. Anybody have any information on whether and when it would be a good idea to change it? Same question for the fuel filter.
  • homemechanichomemechanic Member Posts: 3
    Manufactures have warranty on OS for up to 60K by law. As you guess it, its life span is about that much and most people dont know that. And here is a new discovery for you. AS most car lovers should notice that after about 60K your car does not feel as strong or like when you first bought it. You might say "its getting old"... Not really. If you spend some money and replace your OS now...guess what... your car drives like new. You will notice a considerable chnge in acceleration and shift(for auto)and an increase in mileage on the highway (only)If you usually warm up your car before you drive, well, the wamr up time is decreased. And its all because of a damned OS.
    Good luck and enjoy.
  • rea98drea98d Member Posts: 982
    So how much does this wonder device set one back?
  • corlt1corlt1 Member Posts: 29
    It's between $30 and $60 each. I'm not sure if you one or 2 O2 sensors (I you have 2).

    The one on the passenger side is located just after the catalytic convertor. It looks like a spark plug screwed into the exhaust pipe. It can be seen from the top looking down the fire wall where the transmission dip stick is, BUT you will have to take it off from the bottom. Follow the manufactorers instructions as you may have to use an anti-seize compound.
  • bcollisonbcollison Member Posts: 24
    The sensor after the catalytic converter is a catalist monitor sensor. The ones before the converter are the O2 sensors. My T-Bird has 85,000 miles on it and it runs great. I will replace my O2 sensors this summer as preventative maintenance. My gas mileage has dropped gradually and the O2 sensors are to blame.
  • psc2psc2 Member Posts: 7
    My 95 t-bird has always used a little oil between 3k changes. It settled in at 1qt per 2k at about 50K and has remained there -- now at 85K. I think some of these motors use oil and some do not. I would not consider that level of usage a reason to doubt reliability would you?
  • kinleykinley Member Posts: 854
    every 2k at 85k is OK with me. We have two 4.6's and the one with 35,000 miles goes 5k before needing a quart while the one with 81,000 miles gets a quart every 1.5 to 2k miles. Both drink Mobil 1 10/40 and the gas mileage is great.
  • william43william43 Member Posts: 1
    Can anyone tell me how to remove the right side valve cover on a '97 crown vic LX? The A/C evaporator housing won't give me the 1/2" in the rear I need.(4.6 L engine.)
  • santiago1santiago1 Member Posts: 1
    My wife has 97 cougar with the 4.6 engine and 40,000 miles on it. It has suddenly developed a knocking problem. It does it after the car has been driven a while and is warmed up and seems to be worse when the a/c is on. It doesn't do it while Idling. I have heard several possible causes from friends ranging from a bad EGR valve to a possible computer problem. Any ideas?
  • rea98drea98d Member Posts: 982
    I've never removed the valve cover on my 4.6L T-Bird, but I would not be surprised if the evaporator housing would have to be taken off in order to do it. Modern cars are NOT mechanic friendly! (Why do you think the Ford dealer charges $40 an hour?)
  • richb6richb6 Member Posts: 2
    Knocking problem, have you checked the oil?
  • hughiem38hughiem38 Member Posts: 9
    There are a couple of things to check. Check all the pulleys on the front of the engine for cracks includiong the damper. Have a mechanic check the flywheel for cracks, this one sounds like a rod knocking. Also check the catalytic converter to see if the plate inside has broken loose, you can hear it rattle althought doubt this is your noise.
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