TTAC Commentator writes:
Hi Sajeev!
The car I am writing about today is my winter beater, which is a 1999 Ford Escort SE sedan which says it has a tick over 155,000 miles. The problem I’m having with it is it it getting dreadful gas mileage. My average tank is about 19 miles to the gallon (in comparison that is what my twin turbo straight six Volvo gets around town). Over the winter I replaced both of the o2 sensors and got a marginal improvement (about .4 mpg).
And here’s the kicker: the dumb thing runs perfectly. No error codes or anything. Idles smooth and everything (well as far as Escort refinement goes). When I go on the highway (which is fairly often) I can see upward of 21… If I’m lucky.
Help please! I’m debating on whether to sell it or not due to this gas mileage problem for something bigger (thinking an Oldsmobile Eighty Eight/LSS or if I’m feeling lucky … an Aurora if I do end up replacing the Escort.) Thank you in advance for your help.
P.S. Here’s a list of what has been replaced/cleaned since the fall.
Mass air flow sensor cleaned
New air filter
New spark plugs/ plug wires
New o2 sensors (both upstream and downstream)
New muffler
New tires
Sajeev answers:
It’s funny how well-maintained vehicles occasionally have an obvious problem that’s impossible to diagnose. But going to the beautiful, enjoyable yet expensive and complicated Northstar powered Oldsmobile is the wrong move!
You’ve done the basics, kudos to you. That makes our job easier. Considering your Volvo drives in the same manner (presumably) there’s certainly a minor problem outside of driver error. And I wouldn’t be so adamant if it didn’t happen to me:
Try changing the fuel filter first, then get new/reconditioned fuel injectors.
That’s it. I know you’ve slooooowly been losing power and efficiency. Perhaps you notice a mysterious fuel smell? The injectors are no longer turning on/shutting off correctly. And when you get ’em installed, ZOMG SON, note the instant acceleration improvement and the later MPG lift.
So go ahead and keep it, even if the cylinder head might be a problem in the future.
[Image: Shutterstock user Chill Chillz]
Send your queries to sajeev@thetruthaboutcars.
My random thoughts:
1. Have you checked all of the brakes? Are any of them dragging? If you’ve got a rotor or a drum scalding hot to the touch, that could be affecting MPGs.
2. Have any friends with a OBDII code scanner (or have one yourself)? Hook it up and see if there’s an issue that the MIL won’t indicate. There are lots of codes that won’t trigger the light.
3. How do you describe your driving habits?
+1 on brakes. I had a caliper very slowly fail while my mileage kept degrading (chalked it up to environmentals and aggressive driving). Caliper and line replacement netted close to +5 mpg.
Parking brake as well.
His post implies that it has been tested and isn’t throwing any codes. (“No error codes or anything.”)
I see that now, just trying to rule out ambiguity.
There’s an easy way to tell if the brakes are dragging that’s worked for me before.
Pop off the plastic wheel covers. Drive your normal route. When you’re parked, check each of the wheels to see if they’re warm or hot.
Carefully. That’s a good way to burn your finger if they are sticking. I use a little IR temperature gun instead.
+1. Free with most Harbor Freight purchases (see your weekend coupons each week). I love my lil’ IR gun.
Check the exhaust system, particularly the catalytic converter, for a blockage.
A clogged catalytic converter would produce drivability issues. They’ll usually run OK at very light throttle but fall flat on their face ad mid/high throttle openings.
You’d hear that too. They rattle when they break apart in there.
Not necessarily. I had to replaced the cats on my Jeep due to a CEL, but there were zero issues when driving
That would have been for a cat efficiency code. It would have only affected emissions.
That and wouldn’t it throw a code too?
I agree that the catalytic converter is a likely suspect; if it is original there is a good chance it is getting plugged up.
Before doing anything, including taking out the injectors, I’d try putting a can of Seafoam in a full tank of gas and running that tank of gas to nearly empty. I used it in my boat every spring and was always surprised how it well it cleaned out the fuel system; it was basically a tune up in a can. People have been using it for decades (there are even before and after YouTube videos) and it really does work; for less than $10 and almost no effort it is worth trying.
Good luck.
I don’t agree with the cat. If it was plugged, he would feel it in the performance. The brakes would be my first place to look. Also the wheel bearings would be a good place to look after that. Where all those things listed as replaced, replaced after you started having fuel economy issues or maybe one of the replacement parts are the cause.
Wow, with mileage like that out of that 2L, I’d be looking for a fuel leak. All the Escorts of this vintage I’ve known could score in the 30s.
It’s possible you have leaky injectors, but I’d expect a misfire or at least an O2 stuck rich DTC.
Check the coolant temperature sensor reading with a scanner, if it’s stuck reading cold or cooler than it should be, your fuel maps will be richer than necessary.
I wouldn’t expect an intake or exhaust blockage to cause this issue, if anything, that would increase fuel economy. Dragging brakes, low tire pressure and whatnot or a possibility, but once those thigns have been ruled out, keep looking at the engine management for anomalies. You might need to get someone involved who has a trained eye for this stuff.
I’d think with those MPGs, he would be able to smell if an O2 was stuck being rich. It would be so sweet smelling.
Fuel leak, thermostat operation, compression, ignition timing, valve timing, cam lobe condition, transmission shifting at correct speeds…
My RX-7 has been running really rich and I’ve been getting 10mpg and I’m pretty sure it’s the injectors in my case too. I’ve been putting off getting the new injectors in because after getting to them I might as well do an engine rebuild, replace the exhaust and do any transmission work that’s needed. That’s a scary amount of labor that I don’t really want to think about.
Agreed, but that’s the right move.
I concur, I’d suspect it of running rich. I read in my Volvo’s Haynes manual that the computer in it (the 240) will prefer to run rich instead of lean in the event of a problem. In the case of my car, its primitive OBD system doesn’t throw any codes and it otherwise runs fine, but I get 14mpg consistently. I would start with a new fuel filter, Lucas fuel injector cleaner in the gas tank, and then clean the fuel injectors themselves (look into a Seafoam solution in-car maybe?). This guy claimed a 3 mpg hwy improvement after cleaning his:
youtube.com/watch?v=F8x_qA7rK5I
I thought that was the general setting in cars – when there’s a problem default to rich. Do more modern cars have a lean setting?
Well, I’m also having hot start issues despite having a good compression test. I know my gutted cat and rusted out exhaust is part of the problem with fuel economy as well, but my mechanic and I have both been suspecting injector issues for a long time.
I have all the parts I need except the Racing Beat exhaust. I just need time/money for the labor.
This car is my DD, so I’ll need to pick up some beater to get me to work before I even consider it.
Another option is to pick up an RX-8 in better condition. Their current resale value is low enough to make that an attractive option.
Not all that many of us have the time, shop space, and tools to do much in the way of heavy mechanical work.
FormerFF: RX8s are nice and all but an entirely different ride. I honestly can’t imagine giving up my 10th Anniversary RX-7 for anything short of it being a heaping wreck or it totally breaking my bank account and forcing me to pass it on to someone better financially able.
If you totally love it, I understand, just be aware that restoring an old car is a lot of time and/or money, especially if you are paying retail labor rates.
I don’t honestly know, you would think so but you would also think it would throw a OBDII code if this was the case. The 240 is on the cutting edge of 80s technology so I could see it not throwing codes if there was a problem but simply adjusting itself in order to protect the drive-train.
If it’s running rich, that should be obvious by looking at a spark plug. He’s already swapped the plugs, one hopes the old ones were inspected and didn’t indicate a fuel issue.
If a catalyst equipped car’s mixture is off, generally you’ll get that rotten egg smell from the exhaust.
My guess is that it isn’t air- or spark-related, but is tied to either fuel or else something that isn’t in the motor.
I’d start with the fuel filter and fuel lines (which may not throw a code if they aren’t working properly). If that doesn’t help, then perhaps the brakes or possibly the transmission (if it’s an automatic) are worth a look.
I keep seeing fuel filter replacement as a recommended fix, but fuel filters accumulate crud as they age. This crud slowly constricts the amount of fuel that is able to pass, so I’m not sure how a bad fuel filter would permit more fuel through if it were indeed the problem. Seems like a plugged fuel filter would result in a fuel starvation issue, not poor mileage.
I believe that the injectors could be part of the problem, but they’re about $60 each at rockauto. Is the $240 worth spending on a winter beater?
“I believe that the injectors could be part of the problem, but they’re about $60 each at rockauto. Is the $240 worth spending on a winter beater?”
I would want some definite confirmation before spending that cash, but it seems that the OP doesn’t really have must issue diagnosing by parts swapping, so load up that parts cannon! If I had absolutely no other diagnostic tools at my disposal, I’d at least hit the local pick-a-part and grab a rail with injectors. You can grab an extra injector pig tail and test each injector individually for peace of mind if need be.
Clogged fuel filter –> reduced fuel pressure –> fuel injector issues –> needs more fuel to operate
It’s possible to have some performance loss without it throwing a code or being completely obvious.
No clogged fuel filter will not cause it to need more fuel to operate. The computer will use the O2 sensor to keep the mixture right and once it reaches a point where it needs to add too much fuel to do so it will turn on the CEL.
You are correct a partially plugged fuel filter will not cause bad mpg. It will cause the engine to hit a wall when it needs more fuel than the filter can flow.
A scan tool that allows checking the short and long term fuel trim would easily identify these type of problems…
Are you sure that is correct? I mean do you have some crazy sized tires throwing your odometer off or something? Only other thing I can think of that hasn’t been mentioned is does it have a thermostat stuck open (or removed)? If it isn’t getting warm enough perhaps it isn’t kicking off the o2 sensor and is staying in open loop mode which is rich.
My experience on cars that run too cool (150-170*) is that they do use more gas. A hot running engine can run very lean under light loads, like cruising.
Hook up a scanner that shows the long term and short term fuel trim and see if the computer is compensating for anything. At idle, both should be in the neighborhood of zero. The short term will flucuate a little bit up and down, but the long term should be steady at a low number.
I had a Bobcat that typically got 14 mpg around town. I gave up after rebuilding the engine and transmission (each for other reasons), and replacing all the peripherals. The brakes and tires were fine. It was simply a bad dog.
I’ve never had a worse car for gas mileage, including a V8, and numerous 6s and 4s.
You’re driving a 15-year-old car, which you describe as a “winter beater”. If you only drive it in the winter, maybe it’s just too cold outside and you’re getting normal fuel economy for the conditions?
(Former) Owner of the car here
So I wrote this about a month or so ago, and here’s an update:
I ended up trading the car away to my dad, and I took his Saturn SW. Even though the Escort was a a winter beater, it still got driven year round. Hes been driving it for about 3 weeks now and has been saying that hes been getting 32 with it with a couple cans of Seafoam through the system. So whoever said something about injectors may have been on to something…
And to address mkirk, that is the actual car in the picture. No outrageous wheels to be seen here! (unless you consider 14 inch steelies with hubcaps outrageous ;)
And to Sajeev, yeah I know about the Aurora’s story. Still would like one though (I have an old S80 and I want a Aurora. Am I a glutton for punishment or what?)
Definitely a glutton for punishment.
You know, I considered mentioning SeaFoam…kinda kicking myself for that now.
I’m curious as to what people think Seafoam does for a car. I’m extremely skeptical it does anything other than to improve Seafoam’s bottom line,
It makes a TON of smoke and almost shakes engines off their mounts when GTI owners use it to try and remove carbon build up on the intake valves. So, if you want to do that….
Most additives (fuel, oil, etc) ARE snake oil…but SeaFoam works. I think it is basically a detergent that cleans out residue and varnish allowing things like carburetor floats and internal injector parts to move better.
SeaFoam is the only additive I buy; it is great for gas engines that sit for awhile because it cleans the fuel system, keeps new crud from building up, and removes accumulated moisture from stored fuel. It is good to add to the fuel of something your are going to store/not use for awhile (lawn mover, boat, generator, seasonal car, etc) or to clean out a fuel system that has accumulated various residues.
Not bad for a product that you can get on sale at 3 cans for $20.
BTW, Weltron: your recent fleet includes an Escort, a Saturn, and you desire an Aurora? You are definitely a masochist.
It cleans out your engine like a ghost chili cleans out your intestine, carbon varnish you name it, I had a 98 explorer with 213k on it when I sea foamed it, never seen that much smoke it my life.
Thanks for the update. That 32mpg is right in the ballpark from my experience.
You’re not alone on the sadistic love of the Aurora. In spite of my experience with them, I still kinda want one with throaty mufflers on it. Has to be a first gen one, not that botched 2nd gen version which mostly have the V6 shortstar.
They’re so dirt cheap now, it’s almost worth the investment just to drive the wheels off one for a while.
I flipped a 2002 Aurora 3.5L last year. I had a customer pass away that owned one that had 13000 (Not 130000). His family was going to trade it in to a dealership, but I told them I’d beat any dealerships offer. I bought it, fixed some very minor isses, drove it for a summer, and then sold it within one day of putting it on Craigslist.
See I completely agree on the Aurora. There ridiculously cheap where I am at and it’s very tempting. And strangely enough I like those Second gens. I think they look really good.
@Weltron
I think you need a Jag V12 to complete your trio of masochism.
Goodness no. I’m not that crazy. Though I have thought about a XJ6…
This is the one I would realistically recommend.
en.wikipedia.org/wiki/Jaguar_XJ_(X300)
Late X308 as well but don’t go near them until MY01.
You stop it!
I love that blue one at the top of that article. It’s the right shade of blue with the right wheels. Just needs an all-around matching tint.
I need about $17,000 more dollars to keep feeding my car habit. So financially speaking, is that better or worse than a cocaine habit?
Btw, I drove an X308 in 2000 which looked nearly identical, the only difference was the shade was a tint of green instead of blue (and it was an X380 and not an X300 although those are built on the same chassis).
I wonder if the aura of the Aurora will replace Panther Love…
While that would be Intriguing, I can’t see the Allure of the Aurora changing the overall Vue of the situation.
You all shouldn’t conduct these linguistic experiments without my Silhouette present for supervision. But I understand what you’re trying to Achieva.
I figured someone would Relay them to you, given your Outlook.
Through the Windows like an Oracle.
Oh no wait, wrong topic.
It’s my Civic duty to stop these puns. If an Accord can’t be reached, then I’m going to throw a Fit.
There’s no escape once these guys focus on this game. I’m going to go out on an edge here and say I’ll throw a fiesta once they stop.
I never feel like these puns are NXS of the allowed quantity. Even Marcelo is getting in on these, bringing in models he would need a Passport to see!
@Marcelo
Would you like to be Escorted out?
@Pch101
I realize these rants are the stuff of Legend but I’m sure with enough Vigor we could reach that Accord which could serve as a Prelude to something better.
Corey, I’ll escort you to the local Ford and let you explore (sic). I’ll show you I only need a passport to see an Escape.
Haha!
LOL!
I always thought the Edge was US and parts of EU only.
I wouldn’t consider this to be a Triumph, but this Vibe does Evoque some strong emotions.
Sometimes these threads feel like going on a Safari, but if you can Express your attitudes, Cavalier as they may be, it is better to Venture them.
All this makes me feel Olds!
I’d say it was a combination of the nut behind the wheel and the temps it was driven it. If the injectors were that dirty that they would cause that big of a difference in the mpg there would have been driveability issues.
Nut in question here.
I’ve drove it’s replacement (a Saturn SW) for nearly a thousand miles now. It’s pulled a consistent 32-33 Mpg and between 340-350 miles to a tank. So I think we can safely rule the nut out here.
SL Wagon is a win.
I’m so disappointed. Based on the headline, I was expecting this article to cover Jack’s weekend adventures.
+1
Transmission? I haven’t seen this said yet (I think)
Is it an automatic or manual?
Are you sure that it’s shifting in to overdrive and the torque converter is locking up? If you aren’t seeing overdrive and not seeing a locked up torque converter that might be you’re problem.
Sadly is an autotragic
There’s a lot of stuff on Escort problems here, so I’ll focus on the one thing that there seem to be no comments on: The option of replacement.
Whether to do it or not is of course, up to you. But, I can tell you about the Oldsmobile 88, though. I have a 1995 LeSabre (Same car, with the Series 1 3800). I paid $700 for it three years ago from a junkyard/fix it up guy. It’s the best car I’ve ever owned. It gets about 28MPG on the highway with the A/C on, and it’s more comfortable than my couch.
I’ve been tempted to look into an Aurora, but for sheer reliability, the H body cars are some of the best.
I prefer the Buick, though, because Oldsmobile’s don’t have Dynaride. ;-)
If I ever get an Eighty Eight, it would have to be an LSS. And your points you list about the 3800 are all true. I think myself the Eighty Eights are the best looking of those H bodies. I listed the Aurora because I really do love the things, but rationally I’d have to go with the Eighty Eight.
Agree on LSS, nice styling.
Agree on second gen Aurora*.
*Pearl white only. And they seem to always have electrical issues.
I like how everyone still wants an Oldsmobile.
Actually, I just said that I’d prefer the Buick.
I would drive an 88 in a heartbeat, though.
On other threads on TTAC, I along with others have suggested that GM just have “GM” dealers, with different “brands” with different models (with little or no platform-engineering and overlap). Take the Impala, put old Olds-esque cues onto it, and call it a real Cutlass!
Note of caution on the LSS as my father had one back in the day….the brakes sucked!!! Otherwise a great handling large car.
Check the ECM for engine codes.
Get a tailpipe smog test to determine fuel burn efficiency.
Unnecessary to change out downstream O2 sensor as its function is to check the upstream O2 sensor and burn efficiency. Unless a CEL downstream O2 sensor.
I would have suspected a fuel leak in the return lines.
Cold weather plus a short commute would definitely return bad MPG to. A faulty thermostat that does not block water from the motor in the warm up faze could add to the problem to. Basically the engine block and oil never get to running temp. so the car is running on it’s electronic little “choke” all the time.
I had 2000 Scort for a beater and had the thermostat replaced, and that helped mileage. But I also agree with fuel filter and injectors.
It’s 15 years old, so age wears a motor out also.