Girlfriend and I went on vacation in her 2005 escape. We get to a moderate grade, and the thing has no guts. Had it floored and was struggling to maintain 25 mph, even if I kept it in a lower gear at 4000 rpms. We took it into the nearest place (ford dealership) where they said their diagnostics said new spark plugs should do the trick. They said they would be happy to do it for $600(!!!)–I decided to limp it home and try to same some money. The rig has 138k on it, and besides oil changes, she hasn’t had anything done. I changed the air filter (which was filthy), replaced the spark plugs (which looked awful) with autolite iridiums, and replaced the fuel filter (which was nasty). I also ran some fuel injector cleaner through it.
The problem has not been fixed. It’s still running terribly. It fires right up when started cold, and the high idle is fine. When it drops to the low idle, however it starts running really rough. It still has no power and if the engine is warm, it starts rough. Also, when I’m at really low RPMs, it occasionally feels like the power brakes don’t function properly–the brakes work, but the pedal is less smooth and harder to press. To me, when this happens it feels like the soft, consistent, pneumatic resistance from the pedal is no longer there.
At this point I am completely lost and have no idea what my next step is. Any advice you all could provide would be more than appreciated!
Sounds like maintenance has been really lax on this car. Don’t be surprised if, in the end , it turns out to be a partially plugged catalytic converter.
Yeah, she definitely could have treated the rig better than she has. Is there a good way to troubleshoot the cat conv?
I also suspect a partially clogged catalytic converter on this poor, neglected/abused vehicle.
In addition, I would suggest that the OP check for vacuum leaks.
I agree with first checking for a vacuum leak and also checking for an exhaust restriction.
As for the spark plugs, are the new ones the same as the OEM ones? We sometimes hear stories here about people changing to some other type of spark plug (usually more expensive) and then having issues. It seems safest to me to stick with the OEM ones.
I assume your girlfriend skimped on maintenance to save money. You should point out to her that her fuel economy has probably suffered due to the condition of the car, so she’s been throwing away money on gas all along. You can tell her we said that so that you don’t get in trouble!
Try pinching off the vacuum line from the brake booster and see if the idle smoothes out.
Is a check engine light on?
You’ll need someone to download the fault codes to start. Even if the CEL isn’t lit, I’m betting there are codes stored.
There are a lot of possibilities here, and many come from severe neglect. In addition to checking the codes, I think a compression test and a check for sludge are good ideas.
The cat can be tested using a straight “test pipe” in place of the cat converter. You’ll throw fault codes, but you’ll know if the cat is plugged.
When we first noticed the problem I immediately thought of spark plugs. Before I took the car into the mechanic, I saw that the three spark plugs in front were easily accessible (while the back three were under the manifold), so I changed those in our hotel parking lot to see if that improved the problem. Someone staying in a nearby room said it sounded like we might have a vacuum leak, but I didn’t give it much thought.
I’m not sure how to check for a vacuum leak, but I’ll do a Google on it. At 138,000 miles, I take comfort in the fact that the plugs and fuel filter were long overdue for a change–even though they didn’t fix the problem, they were worthwhile efforts–would swapping the catalytic converter be similar? Should I change it out no matter what, or would it be better to troubleshoot/try and clean it (I KNOW NOTHING).
The check engine light was on originally, but I removed a battery terminal when I switched the three accessible plugs. When I took it into the dealership the light wasn’t on. After replacing fuel filter, air filter, all six plugs, and running fuel injector cleaner, the check engine light is now back on.
I believe the stock plugs were motorcraft some sort of platinum (super?, double?, shiny?, diamond studded?). I went to Napa originally, and they sold me Autolite platinum. I put those in the three accessible cylinders first, and noticed no change. When I got her back to town, I decided to switch all 6, and was recommended the Autolite irridiums. That is what is currently in all cylinders.
Thanks again guys!
I forgot to mention. While changing the plugs, I checked compression. 5 cylinders were between 175-185, and the number 4 cylinder was at 155. My friend, who helped with everything, said that was decent and unlikely the problem. It sounds like having a computer is a really helpful thing right now…my friend who helped me out has software up to 2000, but said it would be pretty expensive for him to update to the point of being able to read the 2005 stuff.
Again, I’m a complete dunce when it comes to this stuff
Those compression readings aren’t very good.
Usually you want the compression readings between cylinders to be within 10% of each other.
I bet if you hook a scanner/code reader up it’ll indicate a misfire code from lack of compression.
And if the engine lacks compression, the engine can’t produce power.
When a catalytic converter plugs up it’s usually because it melts down internally. You can’t clean it when this happens. A restricted converter can cause a low vacuum situation which would explain your loss of power brake assist. It’s vacuum operated.
Your compression readings are high enough so as not to cause the lack of performance you are experiencing.
Here’s my opinion . . .
the compression numbers aren’t very good. I’ve seen better
But on the other hand, they’re not very bad, either
In fact, I don’t think they’re low enough to be causing any misfires
In my experience, once the compression is 100 or less, that’s when low compression starts becoming the actual cause of the misfires
Clearly the codes need to be pulled, and posted here
But I’d say the most important thing is to figure out what’s going on with the power assisted brakes . . . or lack thereof, to be more accurate
It should be very easy to hook up a vacuum gauge and take some readings
Can I go to an auto part store and borrow vacuum gauge/hook into a computer for codes without looking like a jerk?
The compression variation is a problem due to the difference between 155 and 175 and up but I don’t think that is your problem. That’s good enough that it should not be causing the car to struggle at 25 MPH. That compression difference might show up as a stumble at idle, etc.
I tend to think it’s a converter clogging issue assuming it’s not a transmission slippage problem.
The best way to check for a clogged exhaust is with a vacuum gauge. They’re cheap and easy to use. You would have to play around with it for a few minutes to get the hang of it.
Clogged exhaust can show up on a vacuum gauge in several different ways so you would need to refer to the instructions that come with the gauge.
I might ask if the engine temp is running a bit hotter than normal as a clogged converter can cause that particular symptom.
Good ideas above. I’m thinking a problem w/the exhaust system too. That would explain the brake problem.
Note to OP: The brake booster is probably powered by engine vacuum, and vacuum is diminished if there’s a problem with the exhaust system.
Before considering to replace the cat, or to even test for a bad cat, bring all the engine routine service items suggested in the owner’s manual up to date. It sounds like you’ve already done quite a bit of that job. Otherwise you may be paying to diagnose problems that will go away on their own once the scheduled maintenance is completed.
"Had it floored and was struggling to maintain 25 mph, even if I kept it in a lower gear at 4000 rpms. "
I am going to go against the grain here. If the exhaust was clogged would the OP even be able to run at 4000 RPM?
@PvtPublic Flooring it would cause the throttle position sensor to “tell” the transmission to downshift to first gear under a relatively light load. I had exactly that happen in a Malibu I had. In that car the problem was the catalytic converter. I know it doesn’t make much sense.
@“MY 2 CENTS” I understand that "forcing a down shift would raise the RPM. But I would have thought that an exhaust restriction would would bring the RPM down fairly rapidly since the engine can only breathe in as fast as it can breathe out. But then again I have been wrong before, and likely will be again, and again, and again…
@PvtPublic If it hadn’t happened to me I would have totally agreed with you. Look at it this way - if you had the car in neutral with no load it would take very little breathing to rev the car to 4000 RPM or maybe even red line it depending on how badly the converter is clogged.