I am new on this forum so if this topic has been brought up before be patient with me....

My 2002 Ranger, with the base 4 cylinder engine, has had a stumble in the engine since the day i took delivery of it(dec 2002). Despite 5 trips to two seperate dealerships, PROM reprograming, etc, the problem remains. The stumble/rough spot occurs between about 1900-2100rpm. Naturally this translates to between 35 and 45 mph in 4th gear around town.

The truck has about 22K miles on it now and has, in the last 2K miles developed another engine related problem which the dealer can't fix. Maybe one time in ten when starting the truck it starts and then just dies. When you restart the truck fires right up with no problem.

Now, here is what I find interesting. Several months ago when the truck was in for yet another reprograming, I asked the dealer to have his service tech drive the 2003 4 cylinder Ranger like mine they had on their lot(fully equpped, w/5speed) and see if that truck had the same problem. The service tech reported that it had the identical stumble.

So, I would like to hear from any "real world" Ranger owners. Does your 2002/2003 with the new 2.3L DOHC 4 banger have the above problem and have you made an effort thru Ford to get it resolved. Honestly, I am pissed to have spent so much for a new truck that runs worse than my 1976 Datsun 280Z or my wifes 1989 Honda Civic. I am pissed to the point of finding a class action suit lawyer if this is a problem that many of us are having. If I find I am the only one then I will raise hell at the Ford dealership. I will check back on the forum for any answers or comments you might have or write me direct at my E-mail address--CDK456@aol.com

Thanks---Charles

maybe theres a lemon in it some where? sorry man, mine is a auto. 2000 xlt. 30ths. miles no problems yet with mine. haven't heard of any doing that.the only thing i've notice is about 30-35 mph in o/d it wants to surge a little like someone pressing the gass then the brake

I dont think its a lemon, mine does the same thing. I haven't really paid attention to it, but some times when I get back on the gas after coasting it kind of hesitates. Ive noticed a few other things like sometimes it will make a really nasty sound out of the exhaust when it stumbles. The other thing that makes me mad is when I push the clutch, the rpm's hang for a while before they drop. I would like them to drop faster, anything I can do?

Joey

BTW, my truck is an 03' with the 2.3L 5 speed.

Well the thing I learned is that if I want to accelerate from 40mph and Im in 4th gear... I downshift. Yes it does stumble, the air/fuel curve there is very lean so that could be the cause of the problem. They did it that way for fuel economy, the ratio comes back to normal around 3k rpm.

To Calpbrian, yea, i agree it is a fuel/air curve related problem. I just find it hard to believe that Ford did not find the problem to be worth fixing during developement. There are times mine just falls all over itself at the 2000rpm level. I also agree with what someone else said that the problem does cure itself once you climb up over 2500rpm or so. But what is annoying is that the problem exsists right at the "cruisin around town" speed where when you are in light traffic and you have a very light foot on the gas.

Originally posted by RangerFan
The other thing that makes me mad is when I push the clutch, the rpm's hang for a while before they drop. I would like them to drop faster, anything I can do?
Mine will do that until I come to a full stop. No big deal I suppose.

Didn't I read somewhere that the Duratech have a "variable runner" intake manifold, a la' the SOHC 4.6L? You know, a mechanical butterfly switches from one set of (long) runners to the other (short) set as RPM rise? If that's true, could the crossover point be in this 2000 RPM range? I don't know. I could be wrong about the manifold. :nixweiss:

Have the 2001 1/2 Supercab XLT with 2.3 DOHC and 5 spd. About 27000 miles and while I have noticed it stumble sometimes, its infrequently and my rpm does hang up a bit when I push in the clutch but thats a functions of emissions ... the rpm stays at like 100 for a few moments before settling down the minimum stting.
Don't have anything as severe as described in cdk456's initial post.
As for the fuel mapping problem, since this stuff is one of the things modified by a Superchip, I wonder if your problem could be ultimately corrected by addition of a computer chip ? I don't recall anyone that got a chip every having complaints like the above.
And yes, you shouldn't have to go to the aftermarket with your own money, but if Ford won't get off its collective dead ass and correct the problem, what's the alternative ....besides geting a different vehicle ??

-Cajun

Touring... that is on the 2.5 v6
The 2.3 has tuble flaps in the intake that open up between 3k and 3500. They just create turbulence for mixture reasons.

Oh, gotcha :hippie:

Hey CDK456 I have the 01 2.3 And I think I am having the same problem when you start it up. Mine doesn't start and die a lot of the time it will keep turning over like it wants to but it won't and then when I try again it starts up. I have been to the dealer several times and all I get is we couldn't find a problem. And it even did it while one of the techs was standing right at my truck and I asked him did you hear it that time. And they still say nothing is wrong. I have also noticed the surging between 3/4th cruising gear it's like the rpm's are too high for third but too low for 4th. I'm gonna try a superchip and see how that works.

Hey Chuck,

Ok, I guess I will throw my 2cents worth in, so here it goes, remember, you get what you pay for. I am going on the speculation that you have the manual, vs the automatic transmission.

The first thing I would do is get a K & N drop in replacement filter and take off the negative lead to the battery to reset the ECU. This will help with ~ 66% of your problem. I could not believe the difference this made to mine. Second, if you when do the above mod, run 'er harder than you usually would, IE get into the throttle, not red line it, but shift at say 3,500 to 3,750 rpm. The ECU will think this is they way you drive and henceforth give you a richer mixture and helping eliminate most of your lean mixture problems, not all, but about 85 to 90% of it.

I'll give you an example, I drive up to ~ 1,700 feet in elevation every day, I was always trying to do this in fifth gear at 70ish, but the fastest I could get 'er is 72mph, with a tail wind, (remember, I am going up hill). Well this was a mistake and I'll explain why. I needed to be to work especially early last week and well basically drove it hard, IE 85mph in 4th gear, up a 7:1 incline (BTW the ol' Ranger loved me for it and purring right along). The very next day, I tried back to my normal driving habits and low and behold, I was driving my normal pattern and I was pulling 77mph in 5th, where I could only pull 72 before, and only change I made is just one day of driving harder than I normally would, so I am going to make an educated guess, that now my ECU is giving me a richer mixture, due to my exuberant driving habit of one day.

Now, truth be told, I still get the occasional lean mixture, as I can feel the motor go kinda flat, but not a miss, or a hesitation, but I can feel the motor loose about 5% in power and I only experience this when driving at constant lower speeds, so yes, as Brian stated, the ECU is trying to lean out the mixture for mileage.

Now I agree with most of posters here that if you still experience this hesitation, as you describe it, you might be best served to get a Diablo chip.

Just as a side note, I have experienced this twice in exactly the same parking spot at the local recreation park. I had my Ranger go into to "full on choke" mode and it would barely run, black smoke everywhere, etc.., thought I was going to have to get a tow, but tried restarting it 4 times with the same problem and the 5th restart it was like it never happened and off I went w/o any hint of a problem. Now I have this happen twice, so I am speculating that leaving the truck in the sun does something to the ECU, or I have a vapor lock, of some sort, the book is still out on this, so if I experience this in the future, I will let folks know.

BTW, get the K & N drop in Filter, it really gives ‘er a nice little boost. :E

Hope this was of some help !!!

Michael C

There is no doubt in my mind that this is a mixture thing. As some have already said, the computer will adjust to your driving some, so reset it and stick you foot in it for a couple days. I don't think I imagined it, but I noticed mine actually adjust to the way drive when I was breaking it in and getting used to it. The intake really helped me too.

Not sure about you guys with the 5sp woes, i got a slushbox.

Good luck :E

Michael C, I thought I was the only person who has seen this weird behavior in my 2001 XLT. I'm glad I'm not crazy. After sitting all day in the sun, my engine bucked, stalled and ran like crap. I finally gave up and nursed it back to a friend's house. I got out, knocked on the door, he asked me to move it to the side of the driveway, and the dang thing started and ran fine. Drove home, no problems. I always thought it was the PAS going nuts, but it seems like it was the full choke issue you wrote about.
Anyway, I also had issues with the weird torque/power curve on the 2.3's. I'm glad to say most of those were fixed when I installed my Gibson exhaust and Mac Intake. I guess those 2 mods changed the curve to make it flatter. It's much, much smoother, and I don't have to peg the revs to get good acceleration.

Hey Silvertank,

Nope you're not crazy, dang thing actually did to me again, and the only constant I can think of is that I am parking down a slight slope, so perhaps I have a fuel pressue issue, dunno. It has done it 3 times now and it has always been in the same exact place. The first time was really bad, the 2nd and 3rd time the engine was just loaded up a bit, just revved 'er and cleaned itself out. When I take 'er for it's 1st oil change, I will talk to the Tech's.

Looks like you are the one I used as a reference in the Duratec Forum, to install the Gibson Cat Back. Good write up. Do you have the 4.10 RE Ratio, or the 3.73 ??? I hypothesized that if you have the 3.73 RE Ratio that there might not be the benefit that the 4.10 RE Ratio users seemed to be experiencing.

Michael C Out !!!

Michael C,

Dang, after 3 times I would be smacking my Ford dealer on the head. Mine only did it once, about a year ago, and that was it. It sits outside at work all day long, so the "in the sun" idea hasn't repeated the problem in my case. Hopefully, the mechanics will be able to find something. Have them check the PAS, I hear it can give symptoms like that when it goes whacky.

Cool, I'm a reference. Glad to see someone likes my pictures and ramblings. I appreciate the compliments.
Not sure I understand the 3.73 vs 4.10 issue though. I've had good gains with the Gibson and Mac, so I'm very happy. I have the 3.73 gears, and the power curve seems much better matched than it was before. Since the 3.73's are a higher gear than the 4.10's I was having problems getting off the line without excess RPM's. Now, there is plenty of power at low RPM's.
In my opinion, the 2.3 probably needs the 2.5 exhaust since it has 2 exhaust valves per cylinder. I'm not sure if that doubles the exhaust flow per cylinder, but it probably puts it somwhere between the 3.0 and 4.0 in terms of CFM per cylinder. My very unscientific method of putting my hand in front of both a 3.0 Gibson exhaust and 2.3 Gibson, indicated they seem to move about the same volume of air (hot air too, cooked my hand).
I would love to look at 4.10 gears, since I want bigger tires. But, I've heard too many horror stories about bad installs to go that route. I'll just bump the tire size up a hair when the stock tires wear out.
C-ya
George

Ive only had mine do that PAS thing once... and boy did it piss me off when it did. I was drivng down to LA, and just as I entered Santa Barbra, it started running like crap (closed loop) and when I pulled off into a service station and killed it... It stayed dead for 3 hours. Then magically it started again at the dealership... I have no idea why, but it just did. Kept me from getting the header sooner. Wasted 15 gal of gas that day... Oh yeah it was hot and sunny that day too. Heat might be a factor in getting the PAS units to go haywire. Hrm....

OK, OK, so what is the PAS, and what does it stand for ???

Thx Michael C !!!

I also have the 2.3L Duratec. One thing I've noticed about my engine, especially since it's broke in now, is that this engine LOVES high RPM's. If your AC is on, shift between 3750-4000 RPM. If the AC is not on, then shift around 3500 RPM.

It's just the way this engine is designed, don't be afraid to keep the RPM's up, it's meant to run like this. If you are doing 35-40Mph, you are not coasting and you may need to accelerate, keep it in 3rd. This engine actually has enough power to drive 4th gear at only 25mph, but the engine is much more responsive, and doesn't hesitate if you use a lower gear.

The Duratec is a great little engine, you just have to keep it running at high RPM's.

Micheal C, Sorry about that, PAS is the encoded ignition key system. Sometimes it goes whacky and thinks the truck is being stolen. From what I've read, the system doesn't actually disable the ignition, just makes it run like crap. I guess no one wants to steal a truck that runs like a bad lawnmower.

Shack, I'm with you there, I just love to rev this engine. I installed a switch so I can shut down the AC compressor to run high revs. I got tired of switching to outside air and breathing smog, plus I won't accidentally spin my AC compressor to high revs.
http://www.fordtruckworld.com/mygallery.asp?id=5998&album=18682

Opps, and it's PATS, passive anti-theft system. Or as we've come to know it "those damn expensive keys"

Wow, thanks for the info, now that's good data. I gotta speculate a bad connection, or just a bad sending unit, maybe cause mines silver, dunno. :confused: I will bring that to the attention of the Ford Dealership, upon, getting my first oil change.

Thanks Silver Tank, BTW, nice mod on the A/C unit !!!

Micheal C,
Thanks, I appreciate it. I got tired of asking Ford for a wiring diagram and got myself the Ford repair CD. Only took a few minutes to figure out which wire. To me it makes no sense, since the Taurus has the same interior, and it has an A/C button.
Definatley have Ford check you truck at the oil change. You don't want to get stranded somewhere.

George, that is awesome!!! Im gonna have to do that! Now the question is will it keep the compressor form engaging in any other position? Im gonna have to do that!

Yup, the mod basically tells the PCM that the A/C control panel is in a selection that does not use the A/C compressor. The circuit is called the "A/C demand signal" and it replaces the old 12 volt signal that used to just go to the A/C compressor. The newer cars run the signal through the PCM, so it can decide if it's a good idea to run the compressor. The PCM will monitor the pressure in the A/C system to make sure nothing is frozen and keep it from being damaged. It also adjusts the idle when the compressor turns on. Most vehicles have a button on this circuit, so the owner can turn off the compressor in any A/C position. I surmise that Ford decided to save some money and left this switch out of the Rangers. I know that sounds dumb, but multiply a $3.00 switch times 100,000 trucks, and that's a nice bonus for some Ford exec.
Anyway, I've tried using the switch in all the A/C selections, and it does turn off the compressor. I mostly leave mine in "Max A/C" and just adjust the temperature with the switch. It's great that I can run the fan and not have to bring in outside air. Let me know if you have more questions and I'll be happy to answer them.

Well Im gonna be doing that mod soon!!! You should make that a quick write up for the Interior section!!! That is going to have alot of interest!

George,

Just a question on your mods, IE Gibson Exhaust, MAC. Did you put both mods on the same time ??? If not, how would rate the both mods on a scale of 1 to 10.

Thx Michael C

As far as kicking your compressor off at high rpms, if you are not mechanically inclined, any Ford dealer that is authorized as a Crown Vic Police Interceptor orderering dealer can hook you up- the techs that work on those should know immediately what you are talking about. The compressors in the crown vic PI's shut down above 4K (or around in there somewhere). This is definitely a great thing to have. No more fumbling with the knob- the A/C knob that is..... :E

Mine does that... Or rather when I goto WOT it kicks off and I get lots of hot air in the cab... But it sure does jump when that happens... :E

Hey guys, I have enjoyed reading the mail you all have been writing. I have to admit I had not considered going to the after market to fix the problem. Hey, when you drop the cash for new ride it should at least run decently. I don't mind tuning my 280Z but I kinda, sorta expected my new truck not to need to be tweaked for a few years. Having said that i think i will try the K&N route as well as some better plugs for good measure. I did this to my last truck, a 98 Nissan Frontier, and the wifes' Civic both of which picked up more midrange power.

My driving style with the truck is way soft on the pedal and I will admit i tend to keep the revs down around town. On the open road I do run in the mid to high 70s almost all the time and have made several trips of 1500 miles one way where the truck ran at that speed on the interstate for two straight days. These trips also saw a good deal loaded in the truck.

On a positive note the "crank up and die" problem has not occured in maybe 10 days now.

I was interested in the problem several of you mentioned about the truck going into a full choke mode and how you thought it was caused by being in the hot sun. Well, here in Florida that is pretty much all we have and at least that is one problem i have not had. In fact, with the exception of the 1900-2100rpm bucking and the now gone "crank and die", the only other problems I have had have been a bad drivers side seat belt retraction reel, and a bad heater hose both of which were changed under warranty.

About this superchip some of you mentioned--who makes it and what's the cost??

charles

cdk- Glad to hear the problem hasn't popped up again. I kept my truck pretty stock for about a year, then the mod bug hit me. There are several chip makers for Rangers: Superchips, DiabloSport, and Jet. Most people prefer Superchips, with DiabloSport a very close second. The jet chips generally don't perform as most would hope. Brian can give you more info on the Diablo chip. I'm holding off on a chip, as I don't want to run high octane gas, or void my warranty (not yet anyway).

Michael C - The intake and exhaust mods were pretty close together actually, about two weeks apart. The Gibson was an 8, since it sounds and performs great, but I wish I had the stainless system for looks. After I installed it, I realised how bad the intake was, and ordered the MAC. The MAC intake I rate as an 8 also, it really compliments the exhaust, looks and sounds great. I just wish their "Racer's choice" filter was a little more sturdy. The whole Intake is also quiet inexpensive, considering how well engineered it is.

Brian - I did a write up for FordTruckworld and GenEdge, but it's really quite simple. The hard part was figuring out which wire to cut. Once you have that identified, there are many ways to do the mod. You could add a simple switch (like I have), a thermostat, or many other creative ways. I was hoping to find an old supercharger shift switch and put that on the shift stalk; but there aren't any of those still around. I was also looking at the RacerBoy shift knob http://www.thezeb.com/caraudio/varad_racerboy_shiftknobs.html
but I decided a simple switch looked the best for now.

Hey George (SilverTank),

Just wanted to find out if you felt any loss of bottom end when you installed your Gibson Cat back Exhaust, if so, did it the bottom end return, when you installed the MAC Intake ???

Thx Michael C

Hi Michael C,

I didn't feel a loss with the Gibson, it just felt like the truck wasn't pulling enough air to make the exhaust work right. It's hard to describe, but it just felt like it needed something to make the exhaust work better. You could tell that the resonators in the stock intake were killing the performance. With the MAC, there is a huge sucking burst of air when pull on the throttle cable. The rev's come up faster, and the power curve seems flatter. Before, I had to hit about 3,000 rpm to get good torque; now it seems to start pulling around 1,000. I'm not sure if I've lost low end power, since I haven't dynoed the truck. I'm sure the big surge the happended around 3,000 is pretty much smoothed out. If you like that big bang as the engine comes up to revs, you'll be disappointed in the exhaust. But, if you want smooth power (like the V6's have), you'll be quite happy. My brother has the 3.0 V6, and he thinks mine has now reached that level of smooth power. That's a pretty good compliment from him.

Hey Charles,

OK, so I tested your 1,900 to 2,100 rpm problem on my 2003 XLT and I do not have the same problem, but what I did find, was that this is when the vibration through the exhaust is it's worst. IE I can feel in the cab the worst and it vibrates pretty good.

So I am speculating that either it is due to a really lean condition, via from the ECU, or there is some type of turbulence in the exhaust that creates this vibration, it only does this in the 1,900 to 2,100 rpm range.

I would like to request the open exhaust guys to test out this steady 1,900 to 2,100 rpm range to see if this vibration exists with your Duratec 2.3L.

Many Thanks !!!

Michael C

Alright, will test that for you today....

Nope the vibe wasnt that bad at all...

Thanks Brian, in retrospect this may have been a faulty test, due to you having a chip in your Ranger, that might have had the possible "lean condition", programmed out.

I was wondering if we could get Silvertank to test this theory, as I know George does not have a chip and has the open intake and the Gibson Cat-Back.

Thx Guys !!! MC Out

Nope I dont have the chip in there right now...

Hmmm, then I guess at this point we do theortically have a turbulence issue in either the premuffler, or the muffler, or a combination of both.

Perhaps George (Silver Tank), or Cajun can give us somefeedback on any possible lean mixture, or turbulence issues in the 1,900-2,100 range with their Gibson Cat-Back setups.

Thx Guys !!!

Remember I also have the header and they dont.... that might be another way it could be different.

Yep, I agree.

Brian,

Did you feel any bottom end increase when you installed your 2.25" Dynomax, or did you not feel much difference in the bottom end ???

Thx MC

There was some difference in the bottom end but not that much from a normal city driving standpoint but from a high speed/racing standpoint there was most definately a difference... It all depends on how much throttle you are using.