1995 Ford Crown Victoria rough running...

I own a 1995 Ford Crown Victoria. It got 98000 miles on it, with a tune-up in the last year or so.

For the past 8 months, the smell from the underside of the car smelled like rotten eggs. Or, rather, old egg salad. My feeling was that the catalytic converter(s) were going bad and needed to be replaced. I'm not sure this was the cause but I remembered others talking about similar situations.

Last week, when backing out of my driveway, my car lurched a little bit. I don't know why it happened, but since then the car has not run right at all. Later that day the check engine light came on. I had the codes read, and it was P0303. Cylinder 3 was misfiring.

I checked all of the wires from the split distributorless arrangement. All wires sparked. I pulled the sparkplug from cylinder 3 and it appeared to look OK. It had a little carbon buildup on it but nothing I haven't seen before in good sparking plugs. When I turned on the car and pulled the wires off one at a time, the car's idle dipped slightly, so I am confident that all plugs are firing normally. I am going to replace them just to make sure, but I don't think the wires or the plugs are bad.

I replaced the fuel filter but that did not help. I also checked the PCV value and there is vacuum, so that appears to be working correctly.

Since this incident, the rotten egg smell has gone away, and has been replaced by a burning smell.

I have no loss in real power of the car. I can still accelerate rather well, and shifting gears is smooth. The only difference I hear and feel is when taking off and when idling.

Any ideas?

Reply to
Richard Tocci
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could be the o2 sensor

Reply to
Falcoon

Reply to
Chowrunner

I own a 1995 Ford Crown Victoria. It got 98000 miles on it, with a tune-up in the last year or so.

For the past 8 months, the smell from the underside of the car smelled like rotten eggs. Or, rather, old egg salad. My feeling was that the catalytic converter(s) were going bad and needed to be replaced. I'm not sure this was the cause but I remembered others talking about similar situations.

Last week, when backing out of my driveway, my car lurched a little bit. I don't know why it happened, but since then the car has not run right at all. Later that day the check engine light came on. I had the codes read, and it was P0303. Cylinder 3 was misfiring.

I checked all of the wires from the split distributorless arrangement. All wires sparked. I pulled the sparkplug from cylinder 3 and it appeared to look OK. It had a little carbon buildup on it but nothing I haven't seen before in good sparking plugs. When I turned on the car and pulled the wires off one at a time, the car's idle dipped slightly, so I am confident that all plugs are firing normally. I am going to replace them just to make sure, but I don't think the wires or the plugs are bad.

I replaced the fuel filter but that did not help. I also checked the PCV value and there is vacuum, so that appears to be working correctly.

Since this incident, the rotten egg smell has gone away, and has been replaced by a burning smell.

I have no loss in real power of the car. I can still accelerate rather well, and shifting gears is smooth. The only difference I hear and feel is when taking off and when idling.

Any ideas?

Reply to
Phrederik

I suspect you may have a clogged catalytic converter - but, the smells before / after lead me to think the air pump bypass to it (I think it has one) might be damaged, blocked, or not opening. I would think you would get an error since there are so many O2 sensors nowadays but it's worth a look. The other chance would be an injector - look at the wires to all of them carefully.

Some mechanics can tell how an injector is working by listening - they use a wood dowel or a long screwdriver, touch it to the injector, then stick the other end in an ear. If you get it just right, the stick will transmit sound but it has to hit the right spot and also block the other sounds, plugs up your ear. I tried it, I could hear the clicking but clicking or not is about as skilled as my ears got. You could try it.

I did my 100k tune up on my 95 CV a couple of months ago. New plugs and high quality wires. It seems very happy. Oh, I did the 60-70k cleanup of the EGR passages, too. Easy. That's about it since I got it at ~55k...

Good luck -

Paul in Dayton

For the past 8 months, the smell from the underside of the car smelled like rotten eggs. Or, rather, old egg salad. My feeling was that the catalytic converter(s) were going bad and needed to be replaced. I'm not sure this was the cause but I remembered others talking about similar situations.

Last week, when backing out of my driveway, my car lurched a little bit. I don't know why it happened, but since then the car has not run right at all. Later that day the check engine light came on. I had the codes read, and it was P0303. Cylinder 3 was misfiring.

I checked all of the wires from the split distributorless arrangement. All wires sparked. I pulled the sparkplug from cylinder 3 and it appeared to look OK. It had a little carbon buildup on it but nothing I haven't seen before in good sparking plugs. When I turned on the car and pulled the wires off one at a time, the car's idle dipped slightly, so I am confident that all plugs are firing normally. I am going to replace them just to make sure, but I don't think the wires or the plugs are bad.

I replaced the fuel filter but that did not help. I also checked the PCV value and there is vacuum, so that appears to be working correctly.

Since this incident, the rotten egg smell has gone away, and has been replaced by a burning smell.

I have no loss in real power of the car. I can still accelerate rather well, and shifting gears is smooth. The only difference I hear and feel is when taking off and when idling.

Any ideas?

Reply to
F&P

I own a 1995 Ford Crown Victoria. It got 98000 miles on it, with a tune-up in the last year or so.

For the past 8 months, the smell from the underside of the car smelled like rotten eggs. Or, rather, old egg salad. My feeling was that the catalytic converter(s) were going bad and needed to be replaced. I'm not sure this was the cause but I remembered others talking about similar situations.

Last week, when backing out of my driveway, my car lurched a little bit. I don't know why it happened, but since then the car has not run right at all. Later that day the check engine light came on. I had the codes read, and it was P0303. Cylinder 3 was misfiring.

I checked all of the wires from the split distributorless arrangement. All wires sparked. I pulled the sparkplug from cylinder 3 and it appeared to look OK. It had a little carbon buildup on it but nothing I haven't seen before in good sparking plugs. When I turned on the car and pulled the wires off one at a time, the car's idle dipped slightly, so I am confident that all plugs are firing normally. I am going to replace them just to make sure, but I don't think the wires or the plugs are bad.

I replaced the fuel filter but that did not help. I also checked the PCV value and there is vacuum, so that appears to be working correctly.

Since this incident, the rotten egg smell has gone away, and has been replaced by a burning smell.

I have no loss in real power of the car. I can still accelerate rather well, and shifting gears is smooth. The only difference I hear and feel is when taking off and when idling.

Any ideas?

Reply to
Pygoscelis Papua

tune-up in the last year or so.

like rotten eggs. Or, rather, old egg salad. My feeling was that the = catalytic converter(s) were going bad and needed to be replaced. I'm not= sure this was the cause but I remembered others talking about similar = situations.

I don't know why it happened, but since then the car has not run right = at all. Later that day the check engine light came on. I had the codes = read, and it was P0303. Cylinder 3 was misfiring.

Is the P0303 still present?

If so I would concentrate there. Keep in mind that the code will not clear until the diagnostic for the misfire code is run under the same engine speed and load conditions that were present when the code set.

All wires sparked. I pulled the sparkplug from cylinder 3 and it = appeared to look OK. It had a little carbon buildup on it but nothing I = haven't seen before in good sparking plugs. When I turned on the car and= pulled the wires off one at a time, the car's idle dipped slightly, so I= am confident that all plugs are firing normally. I am going to replace = them just to make sure, but I don't think the wires or the plugs are bad.

This doesn't convince me that the plugs/wires/coils are good.

It may be easier to check the injector for number 3. Disconnect it and note the RPM change and compare it to several other cylinders.

PCV value and there is vacuum, so that appears to be working correctly.=20

replaced by a burning smell. =20

well, and shifting gears is smooth. The only difference I hear and feel = is when taking off and when idling.

Reply to
saeengineer

A rotten egg smell like that indicates the catalytic converter is working heavily, likely because of excessively rich mixture or a misfiring cylinder. If you still have a P0303 showing up, then you do have a misfire. Could be a fuel problem, but more likely you have a bad plug, wire or ignition coil for that cylinder.

Reply to
Robert Hancock

You need to do a power balance test on all cylinders to see if 3 is misfiring.

another possible thing is the ignition module is going bad. They can cause a single coil to be firing weak or be off in timing.

Or you can have a stuck injector. Leaking too much fuel into the cylinder. You need to check the fuel pressure, see if it holds at pressure with the car off.

Also, you can do a injector balance test.

Reply to
Erik

Paul, Just how easy is the job of cleaning the EGR passageway? I was told that since you have to remove the throttle body assembly and accelerator cable, that the accelerator cable/connection has to be "re-calibrated". Thanks, John in N.C.

F&P wrote:. Oh, I did the 60-70k cleanup of

Reply to
Chowrunner

It was very easy. I am fairly sure the cable has a pop-off connector at the TB but it was a couple of years ago... I may have just undone everything else and laid it to the side.

I stuffed a rag into the manifold after I got the elbow off and chipped most of the guk out with a small screwdriver. I used a shop vac to catch the chunks. Final cleaning was with blasts of TB cleaner (not carb cleaner) and a wipe with paper towels. I cleaned the elbow and TB at the same time.

There is a gasket between the elbow and manifold. I was able to reuse mine (Sunday job, Ford only part). The guk is in the lower channel, below the gasket. I can't figure out why it's made that way but it works wonderfully now.

Paul in Dayton

Reply to
F&P

I would add that you should check for vacuum leaks. However, given that you are running rich I would suspect that it's not just that.

Reply to
Childfree Scott

I would like to start by thanking everyone that contributed thoughts and suggestions on my problem. All help was taken when trying to fix my car.

After looking at everything written in this thread, as well as reading up in a couple of books, I figured my problem would be solved in the following order:

  1. Replace spark plugs
  2. Replace wires
  3. Replace both ignition coils
  4. Replace the fuel injector

As a side note, I was NOT looking forward to number 4 in my list. They are $70 each, and since I have 8 of them, and was not looking forward to THAT cost factor.

Anyway, I bought 8 Bosch Platinum spark plugs and gapped them to .054. I don't care what they tell me, I always gap spark plugs. OK, one was gapped at .055. Sue me. I replaced all eight. Cylinder 3's plug was black while the other 7 were white. This told me that the 7 were running hotter than normal, and 3 was definitely misfiring. The other 7 were trying to take up the slack of number 3. Replacing the plugs improved performance but did not fix the problem. In fact, a couple of days later, the condition was like it was before I replaced the plugs.

Yesterday I replaced just the number three spark plug wire. I need plastic ties because some cross over the engine, and without the ties, wires will be hanging into the fan housing. Number 3, fortunately, was not that big and did not cross over to the other ignition coil. I started the car, and the problem was solved. It runs better than it has in a long time.

As a computer professional, I should have realized that the simple answer is usually the best answer. Thank you for all of your help. You saved me quite a bit of cash in labor costs.

Reply to
Richard Tocci

Did you run a compression test on cyl 3? How about checking the intake manifold for a leaking manifold gasket? Have you removed and inspected the EGR valve for debris holding it off seated position?

Reply to
Philip ®

Reply to
Thomas Moats

Me bad... didn't read the entire post before replying.

Reply to
Philip ®

Reply to
Thomas Moats

I would suggest replacing the other wires as well, especially if they are original. I replaced plugs and wires as a 100k miles tuneup on my CV - it seems a lot smoother, now. (the old plugs didn't look bad, either)

PoD (was F&P)

Reply to
Paul of Dayton

I'm doing that tonight. I had other functions to attend to, and I had to buy cable straps for the wires that cross over the engine to the coil on the opposite side.

Reply to
Richard Tocci

I figured you might but wanted to be sure I understood your message correctly. I was really surprised what a difference plugs and wires made.

PoD

"Richard Tocci" wrote in message news: snipped-for-privacy@corp.supernews.com... I'm doing that tonight. I had other functions to attend to, and I had to buy cable straps for the wires that cross over the engine to the coil on the opposite side.

Reply to
Paul of Dayton

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