So here’s the synopsis: My girlfriend’s 2001 Ford Escape V6 4x4 with 196,000 miles had the check engine light come on two weeks ago. The code read : running lean and misfire in 4/6. Changed all plugs and coils, engine light was still on, still running lean and there’s a vacuum leak. Changed all intake gaskets, light went out. NOW it’s sputtering and the exhaust manifold turns cherry red (clogged cat). Changed the front cat & Y pipe, remove back cat. Also replaced muffler and resonator.
Car STILL sputters and idles around 200 rpm. Now it stalls when turning around or coming to a full stop, and exhaust manifold still heats up enough to turn cherry red.
Anyone have a clue as to why this is happening? SERIOUS ANSWERS ONLY PLEASE! No bashing just because it’s a Ford. It’s been two weeks and I need to know if there is any hope to fix this, or if it should just be scrapped.
If you’re certain there are no vacuum leaks and no exhaust restriction (which I assume there are none) maybe the fuel system is running excessively rich.
An idle that drops very low like that is often due to a vacuum leak or overrich fuel/air mix if it’s not related to an Idle Air valve or throttle body issue.
Are there are DTCs being set now and if so what are they?
I can’t help you with the cherry red exhaust. But, I do want to say on this forum there is not extreme hostility to Fords. A couple Ford models are actually great cars. Examples: F150 pickup, the now obsolete full sized Crown Vic sedans, and a couple of small cars have done rather well for their owners.
You are throwing parts at this car without diagnosing what the real problem is.
Instead of replacing the coils, you should have swapped them with two that have not tripped a code and clear the old codes. Then if the misfire follows with the moved coil, you would know it’s a bad coil.
All that money and it could be as simple as a vacuum line that is cracked.
When you decided to remove the cat…if you had started it then…without any pending codes and it ran just as bad the cat would be good.
Check the power brake booster. The large vacuum hose that goes to it may be cracked.
Sometimes these are hard to find if the crack is on the bottom side. Then check all the vacuum lines for cracks.
...exhaust manifold still heats up enough to turn cherry red.
Are you talking about the top of the cat converter(s) or the three pipes of the manifold that go to it? On one bank or both?
It has to be running extremely rich to glow cherry red. The only other time I have seen this is when someone reduced the restriction on the exhaust flow so much that it scavenged fuel from the cylinders and was burning in the headers. They put on headers, high flow exhaust and the exhaust had too little back pressure. I wonder if it’s something as easy as a temp sensor that is keeping it rich. Is the check eng light on? The IAC could need cleaning. Here is a guy with a 200rpm idle. https://www.youtube.com/watch?v=0liDtBLIu-4
There are no codes,I am not throwing parts at the car , I’m taking it one issue at a time.!
Had plenum orings go out on a 2003 ford 6 cyl, but had a check engine light also. Left bank lean was the code description if I recall correctly.
Found this while I was looking for more info on orings
"Our 1998 Exploder has been doing this for several years, only the initial start of the day (ALWAYS does this when it gets cold, and worse as it gets colder)turn the key and it sputters and has troubling staying running for a few minutes, you have to nurse it to keep it running. I had replaced all the sensors over the years, new fuel filters, pump, and on and on…threw $100’s of dollars at it, it never popped a code to tell me what was wrong with it…took it twice to the Ford dealer and all they could do is scratch their heads and tell me “We are not sure”…so, this past weekend I took the intake apart and cleaned out all the carbon and other gunk in it, used a (1/2 gallon of lacquer thinner and 3 cans of carb cleaner) put in NEW, upper and lower intake gaskets, put it all back together, and it started right up, and now it acts like a new motor, it has a lot more giddy up to it. This morning it was in the upper 30’s and it popped right off and ran like it never has in the past few years. So, yep, I fixed it! It took me about 4 hours to accomplish it. Worth every dime and hour spent…oh yeah the gaskets were only about $25…sure wish I had known about this a long time ago. - Visitor"
The the pipes coming out of the block, if you stand back you can see the whole manifold cherry red .
Does the vehicle seem to run well once rolling or does it feel somewhat sluggish?
Is there an acrid smell at the tailpipe?
My first thought was clogged cat but that was apparently replaced. That leaves vacuum leaks, running too rich, and excessively retarded ignition timing.
The latter is really grasping as there is no distributor. This would have to mean some oddball PCM anomaly that is causing the timing to be excessively retarded. If this was bad enough to cause the exhaust manifolds to glow red the engine should be running very sluggishly.
Maybe an EGR valve sticking wide open?
It is running a little sluggish on a test drive , egr is a long shot but still worth a try .
Running rich is the cause for the hot exhaust? I thought the OP said the code was for lean. It’s sort of surprising, but the combustion can get extra hot in lean conditions. Lean means there’s plenty of extra oxygen in the combustion chamber. And that’s like wind blowing on a campfire, it can cause a fire to get really hot. I expect the lean condition is what is making the exhaust temp so hot. Cat problems can cause this too, but it sounds like that’s already been addressed. Good idea above about checking the ignition timing too.
Lean conditions are caused by some combination of too much air or too little gasoline in the combustion mixture:
Vacuum leaks allowing unmetered air to get into the intake manifold; e.g. brake booster sprang a diaphragm leak.
Intake manifold leaks.
MAF or MAP malfunction
Throttle body or IAC leaks
Fuel injector seal leaks
O2 sensor malfunction
If there’s a sort of rubber boot between the air cleaner and the throttle body, check that for cracks or breaks.
Just my two cents but I screwed up a wire and plug change so had one plug wire not firmly connected and a couple wires crossed. That was enough for my exhaust to glow red after about 5 minutes of it running rough. Shop fixed it no problem but two days later my $700 cat was shot. Just running a few minutes red hot before calling a tow was enough to ruin the cat and it would have been running rich due to the ignition issues. I hope you haven’t ruined a second cat. Sometimes its just time to let someone have a look at it for a hundred bucks.
still running lean and there’s a vacuum leak
These things will make a manifold GLOW…and trust me…you dont want that happening. There is something wrong with the FUEL METERING on this vehicle. MAF? ANY and ALL vacume leaks must me located and repaired.
I need to think about what I did to solve this a few years back… I have repaired several vehicles that were trying to use their exhaust manifolds as flashlights … Each was unique but all were generally a combo of lean fuel…and advanced timing.
This vehicle may be suffering from an ignition timing problem…which would ALSO affect the timing of the injector firing… If you are not a proper ignition/valve timing…you will easily glow a manifold… Whats worse is that if the timing is off…the injector pulse is also incorrectly timed…
Methinks the problem lies somewhere within this realm…and I cant do better than that sitting at my computer chair. Im thinking about stretched timing chains, all the possibilities that simple sentence holds and the symptoms you would see.
So let me ask this , If I did a basic tune up i.e. Coils, plugs, intake gaskets and oil change . What would cause the timing isseu ?
The 196K on the odometer would have. At that mileage the Timing Chain has basically reached the end of its useful service life. There is no doubt that the chain has stretched considerably at this point. Its possible to jump time at that point… However when it jumps time…it usually or rather always jumps in the Retard direction. Which means the crank gets ahead of the valves. However nothing is impossible when you have a lot of slack in a timing chain. Ive seen many things I cant explain without assistance once the chain is no longer at proper tension.
Any time I have seen a glowing manifold it was due to incorrect ignition timing…which also affects the injector timing as well. A LEAN BURN condition will certainly glow a manifold NOT A RICH MIXTURE…A rich mix will NOT GLOW A MANIFOLD… An incorrectly timed injector pulse can also contribute to the lean condition such as a late firing injector…this would mimick a lean condition as well.
Let me do some homework for you on this. I have to think about this one a little bit
A Vacume leak will glow a manifold and incorrect ignition timing will also glow a manifold. Those are the ONLY two I am aware of… I’ve only been doing this for about 28 yrs now and those are by far the TOP TWO items when dealing with a glowing manifold.
People are often confused by this condition…they THINK that a rich fuel mixture will cause this…but that is 100% incorrect.
I THINK this engine has PLASTIC intake manifold? Let me know if that is correct…
OK…there is a WEALTH of MIS-INFORMATION out there… Many many people are very confused when it comes to this subject.
Rich mixtures will actually COOL the exhaust… I know this sound a little counter intuitive but Dems the facts.
I am trying to nail down which camp is correct about the ignition timing. I was ALWAYS under the impression that Advanced timing will glow a manifold… I am trying to see if I have been correct all this time.
There is so much WRONG info floating around that I am beginning to confuse myself with some of it.
I am certain about the lean condition…this will glow a manifold like a light bulb.
All I need to confirm now is which condition in timing will also do this… I was under the impression that ADVANCED ignition timing is the culprit… HOWEVER I am seeing many a guy state that a Lean condition…AND RETARDED ignition timing will glow the mani…
I need to look into this…Because if Retarded ignition timing Does indeed cause this…(and not advanced timing) THEN… You are a PRIME candidate for retarded ignition timing… This can come from a stretched timing chain very easily…
I apologize that I allowed the mis-information on the net confuse me…because I actually DO know my S&*^ when it comes to engines.
I need REAL engine guys to chime in on this one… I was under the impression that Advanced timing would cause a manifold to glow…and I have actually seen this in practice. How could Retarded ignition/Valve timing cause a manifold to glow?
I need to research which flavor of ignition timing is more Apt to cause this (My whole life I believed it was advanced) So if its retarded ignition timing that is the culprit…I will be surprised. However…if it is indeed retarded timing as the winner…Then this engine is a major suspect of being able to jump time to a more retarded position due to cam chain stretch.
Sorry I let myself get confused here…Im a little embarrassed