I read somewhere in here that a test for a bad clutch is to get the car up to 20MPH, stick it in 4th, then floor it. If the engine takes off or the car shudders, the clutch is gone, baby, gone. If the engine just lugs and is steady in trying to accelerate, then the clutch is not bad... yet.

I did that test, and sure enough, Awesome acts like she doesn't have a clutch problem. Yay.

So... now I'm confused.

See, I thought she had a slipping clutch, but it just doesn't let go like it should with that test. At all. However, on acceleration and cruising up a hill (say, even a bridge on a freeway over an intersection) it seems like there's a little... throttle blipping going on. Maybe even a miss? I dunno, something. It felt like the clutch slipping, just ever so slightly. I don't know how to describe it. Maybe a little hesitation, maybe a slight miss, but... something.

The following information is probably needed:
Newish Air Filter (I think... yeah, pretty sure... I may need to double check that, but go with 'yes' for now.)
Throttle Body Cleaned (removed, cleaned, reinstalled.)
When that was done, reset the computer, and reset the throttle. That was a while back.
I've reset the throttle today as well.
Running 93 Octane.
Various forms of acceleration, but not by default '******* it'. I do run her up now and then, but the grand majority, normal take offs and driving.
Tires are good, no pressure problems there.
CVs/Universal joints and all that seem to be lashed up pretty good... no real slack, everything looks and feels normal.
56000+ miles on her
Oil is changed, and other maintenance items are performed, on schedule. Next up is 60,000, by the book, unless something comes up, of course.

I am the second owner, so I don't know what happened in her first 20,000 miles of service. Seems like some lady owned her down in Brownsville/Harlingen , previously, but that's all I know.

I am open to any and all thoughts and ideas. Anything. She's just not acting right, it feels like to me.

In every other way, she's great. No issues. Just this little semi-hesitation I can feel in her stride.

/maybe I'm too sensitive.
//The prince and the pea?

 

if the air filters been changed recently, make certain its seated well...they had a old aerostar work van at the shop, wasnt running, they had my buddy working on it- he replaced a bunch of stuff, just wouldnt run right...I was bs'ing with him about it, went to look at it, noticed the filter had a fold in the gasket- maybe leaking air/might cause turbulence around the MAF...yeah right...well, got the filter to lay down snapped the lid back on, everything was fine...he was pissed. apparently some cars are very sensitive to airflow coming straight into the MAF, a leak can really screw with the sensor.

on the possibility of the clutch slipping, I agree it sounds ok, but remember our torque peak is at like 4500 rpm...at first starting to fail, it will slip up in that range I think...could like half throttle take second up to 4k (about 50?) then romp on it- if the tach flashes up to redline without the speedometer hitting calculated mph, its toast, and will very soon be slipping at lower rpm/loads also...3.55 gears should put you at 72 mph at 6250 in second if I did my math right...so if you see it heading for redline at 60, its slippin.

Sounds though like youre describing a part throttle situation, I'd look more at the possibility of just bad gas, a intake leak, dirty injectors, fouled plug(the one piece/neverseize fouling might be a possibitlty if theyve been changed recently) or a bizillion other things the way these things are computerized...hope its just something simple

 

Great advice, Tim!

I checked the filter and top... no issues, it's flat, not pinched, just about as good as it gets.

I then checked the tube fittings, making sure they weren't pinched or such.. they're also good. Bands are tight.

I checked for loose pipes, tubes, connections, etc, and found nothing. The air supply should be fine.

The clutch is absolutely not it now. All tests indicate good grab, no issues. It's not smelling either, and I've been trying to make it upset today. I will knock it off now, of course.

I had someone say 'fuel filter', and I wanna say it's been done, but now I can't remember. Might just do it 'because'. Cheap enough, after all.

I did have an episode where as I was in second and going about 20 or so, hammered it, and it stuttered a little.

Now, one thing that came to mind as I got home, I turned off the A/C, and lo and behold, the car all of a sudden stopped it's antics.

And then I thought... Perhaps the accessory belt is worn out? I wanna say it was replaced when they took it in at the dealership, but in reality?

If it wasn't, it's got about 57K on it now I suppose, but it looks fine. (my 56K was off a little in my head, it's closer to 57) My thinking is if the tensioner is run out because the belt is done, maybe the A/C is letting it slip about, causing the slight hesitations as the a/c 'grabs and slips'. Anyone got a pic of 'new' vs 'worn' on the tensioner? I can't really tell...

Other than that... Maybe a retrain, or some fuel injection cleaner, or... sigh... spark plugs. I just don't wanna. I'm afraid of them...

/really leaning towards the fuel filter, honestly. That seems most likely now.

 

something to maybe try- some say its bs, some say it helps...I say it makes mine act better...turn the key on without starting, when the airbag and whatnot lights go out, press the gas to the floor and release, then turn off the key and wait like 5-10 seconds before starting the car back up...I'd read it recalibrates the pedal to the throttle body, then read, bs- it only works on dodges, but I swear whenever mine gets balky, If I do that it behaves like a new car again. dont cost anything to try...

lately in hot weather mines been a dog...a/c always slows them down a little, but Ive noticed the past month its really a toad till over 2500 if the a/c is on- oddly it seems WORSE, much worse, if I run premium fuel...(I get 20 mpg on 89, only 18 on 87 in my daily commute...usually put up with the kinda sluggish bottom end for fewer gas stops...10% better mileage for like 2% more cost...) odd how good 89 (sunoco) seems to kill the bottom end torque, but gives better MPG... I'm still 100% stock, really need to get a tuner, my freebie 5/75 warranty expires this Dec anyways- glad to say never needed it, Ford gave it to me when the first one got smashed at delivery- I'd have rather had that test drive.

I hope to go to the track tomorrow- supposed to be hot as heck, wont be busy, but I need to get back out there I changed the oil tonight, wiped down the undercarriage, for nearly 5 yrs old(no winters, but rain or shine I'm driving it till the salt comes out) it still looks great underneath- no signs of ANY corrosion anywhere yet- except that unpainted rear axle...other than the rear axle and the exhaust tubes not shiny, it looks like new still...will polish up the exhaust pipes/paint that axle over the winter...been saying that for a long time though

 

Fuel filter is supposed to be changed every 30K anyway so I'd be doing it anyway. Possibly plugs but kind of doubt it at half their service life. (Unless they are carboned up that bad.)

 

I don't remember where I read it, but someone was having some isseus that went away once the throttle body was cleaned. I had mine off yesterday and checked it, and even though it didn't look all that bad there was still a distinct ridge of crud at the top and bottom of the housing.

 

houtex, I'm pushing close to 68K on mine, and am having a similar random 'stutter' when driving. Usually isn't prevalent on heavy acceleration, just when cruising. I'm thinking it may be plug related. I'd like to get my hands on a IR thermometer and check the temps on the exhaust manifold, but I don't know if I'd be able to get a good read, with them being cast iron and a single log. It'd be real easy if she had headers to check, though. Like you, I'm not looking forward to messing with the plugs.

 

BTW, throttle reset for me is that whole gas pedal down thing. But definitely, it DOES work.

Fred, the problem started AFTER cleaning for me. It's only been about 600 miles. I was having trouble with really bad throttle response, and that fixed it up after resetting the computer... but now this.

I hear ya Nick.

I have been looking into the A/C thing, and it sure does seem more and more likely. When the A/C's off, it doesn't do it. When it's on, easily done.

Still lookin'... hard to do, no garage, no time... But I'll report as I learn more.

 

This kind of sounds like a fuel pump issue. Is there a way you can check for fuel pressure? I remember people complaining about similar issues when that fuel pump recall was going on.

 

Mine does the exact same thing...only when the A/C or defrost is on. It only happens when the compressor cycles on. It has happened since new. It is normal. At least your problem sounds like that anyways.

 

There should be a TSB floating around on the fuel pump issue. Not sure if there is a good diag procedure.

 

re: compressor: No, it's not normal. Normal would be when it cycles, but it's not cycling. It's on, and not going off. I'm not hitting it that hard for acceleration to cause it to go off, and I've got it on Max A/C. I also could tell if it is on or off. This isn't the issue... unless the compressor itself is having stuttering issues, THEN it may be it. Hm.

The only diag on the fuel pump is to put a pressure gauge on the fuel rail, which could be done.

---

Updating: It is *definitely* only when the A/C is on. I have been running with the windows down (it's been cool enough today) and it is absolutely GONE with the A/C off.

I'm starting to think it's the belt, the A/C clutch, or maybe the compressor now. The belt is easy, but the other two... especially that last...

 

Even with your AC on MAX, the compressor still cycles on and off. All MAX does is recirculate the air instead of pulling fresh air. Listen for an audible CLICK when it cycles on/off coming from your engine bay.

 

It should cycle to maintain pressure consistent. On at 30psi- 0ff at 45psi low side. It repeats this cycle. Should never be always on or high pressure side could reach dangerous pressures. You have the cycling switch in the low side, and 3 ac pressure switches on the high side to turn off your compressor if high side gets too high.
The little tremor is normal when the the clutch kicks on. depending on the the temperatures it could cycle every 10 seconds avg.

 

Repair your ac system, if the clutch is staying on always. Could be a faulty pressure sensor, relay, circuitry, or the A/C clutch air gap.