99 X flat spot/hesitation

[james t]

yes, it has the damper, but from what i understand it is "built in" to the fuel pump itself. either way, you got the problem fixed, and that is all that matters.

 

[V8-X]

Well, about 1-2 days after the reflash of the PCM, the problem was back. Took the X back to the Dealer, who could not find anything wrong. He has spoken to a Ford Engineer that wasn't able to suggets anything that would be causing this problem. So now the Service Manager is going to try and find a 5.0 X on the lot. He stated he will then compare each test side by side (my X vs X on the lot). This is "IF" he has a 5.0 X on the lot. This is where I am at now. Don't have a date to bring the X in, but the Service Manager is going to call when he knows if there is a 5.0 X on the lot. Anything I should have them compare, or look at specifically? Thanks for the help everyone!

 

[fordkrazy]

have them compare the values for the injectors, TPS and the PFE since these would be causing performance problems. It really sounds to me like an EGR problem.(the TPS tells the computer how much the EGR can be opened and it usually opens more at lower RPM's when its crusing cause less power is needed....when you hit the gas more the EGR should close up to give a little more power and at WOT it should be closed all the way thats why your seeing the hesitation below 2k) I dont know if a bad injector would cause a misfire like you had once but it may. You may want to open up the intake plentum to see if the EGR curcuit is crudded up bad. i dont know if the factory ones open on the side but you may want to look into that.
good luck man

 

[V8-X]

Well, I just had another shop take a look at the X.

They found 1 crack plug (has been replaced), and they determined that the FPR was bad. Already replaced the FPR back in Sept. '02, but had them replace it just in case.

The X now has a considerable amount of it's power back, but not all the power it should. I no longer receive a buck or stumble, but it still seems to slightly bog down. The problem (lack of power), is still most consistant below 1700 RPM's,which the speedo is around 30-40mph (o/d off) or 40-50 (o/d on), and hills still seem to be a struggle to climb. These symptoms seem to come more often when I try to accelerate from a cruising or coasting speed in the above speed ranges. I know when the problem is going to occur, because the exhaust tone gets a lot deeper and echos throught the cab (deeper than normal tone) which is either right after the Torque Converter locks up or when it shifts into 3rd gear (feels like the truck shifts or locks the TC). When this happens, the engine tone seems to change and I get a vibration through the gas pedal. Also when this occurs, the gas pedal becomes squishy/spongy/soft or less restrictive than usual.

I'm glad to have a lot of the power back, but the X is still not running as it should.

A Dodge Caravan made me look like I was standing still last night when we were climbing a hill. We both took off from the same stop light, and I was giving the X about 3/4 throttle, but the Caravan just left me behind. This is crazy, V8 X vs. V6 Caravan and the Caravan takes the X.

Any thoughts on where to go next would be beneficial.

Replaced: EGR, TPS, IAC, FPR (twice), 4 O2's, 8 Plugs & Wires, Fuel Filter, PCV, reflashed the PCM (by Ford) and cleaned the MAF. Each item has seemed to give a little power back, but not to fix the problem.

Again this is a 1999 X V8 AWD w/AT @61K-miles.

Oh, and I'm still averaging 13mpg (city) where prior to the problem I would average 16mpg (city).

Thanks again for all the support and help! Just wish I could get this V8 X to act like a V8 X.

 

[fordkrazy]

have you checked into the auto transfer case for the AWD? does your ABS light ever stay on after you hit the brakes? it could be a sign that the TC is engaging more often than it should....just a thought. could be a tranny problem with a bad or clogged circuit valve? torque conv. could be locked all the time. (is there drastic change in RPM between shifts?)
with all that you have replaced i think you have exhausted all efforts on the engine and you should look elsewhere. (except reclean the MAS and make sure you use chloride free brake cleaner so there isnt a residue left behind like carb cleaner leaves)

Good luck and sorry your still having this problem
i feel your pain

 

[V8-X]

Haven't checked into the Transfer Case and have only had an external diagnosis done on the Transmission. The ABS Brake light has never come on, except on start up. Now when it does shift, it seems like it shifts to a lower RPM than prior to when the problem started. When traveling around 35-40mph (o/d off), it feels like the transmission shifts & the RPM's drop about 200-300. This is when I beleive the TC is locking up, and when the exhaust tone gets really deep. Once this drop in RPM's occurs and the exhaust tone gets deeper, is when the problem is most noticable. Also, I get a vibration through the gas pedal during this time. This vibration occurs until the next time the transmission shifts. Thanks again for any further advaice on this annoying and on going problem.

 

[fordkrazy]

well 200-300 RPM drop isnt bad...thats pretty normal (the 5spd RPM differance is 1000 from 1st-2nd-3rd and 500 between 3rd-4th-5th)

i would look into having the tranny flushed and the transfer case drained and refilled. and like i said earlier...reclean that MAS w/ brake cleaner not carb cleaner

 

[V8-X]

I'll go ahead and take the X in to have the Transmission & T-Case serviced and checked for problems. Now the MAS has been cleaned a couple times. Once by myself, and the most recent time by a Ford Service Dept. Hopefully Ford used the correct cleaner, but I'll get in and clean it one last time. Just in case. Thanks for the help, and I'll let everyone know what's up once the T-Case & Trans. have been serviced.

 

[scorgnetic]

V8-X

Just want to let you know that this sounds like the same problem that I am having with my SOHC 6. I have replaced the FPR, plugs and wires and it was all to no avail. Please keep this updated as I know that I have posted this before and so have other people and I have yet to see anybody solve the problem.

Randy

 

[V8-X]

scorgnetic - I'll let you know when I find something out about this.

Like you I have also seen many posts regarding similar problems like this, which no one is has been able to determine what the problem is. I see this problem more with the V6 than the V8, but that's probably due to the volume of 6's vs. 8's.

Like wise, if you find the cure let us know. I'm almost to the point of trying anything to get the X running right again.

 

[SMASHEK]

Did you Solve It?

Were you able to solve the engine misfire? I have a 1998 and around 1500-1600 RPM I get a really bad misfire. I am trying plugs and wires since I have them but I wondered if you solved your problems and if so how.

 

[V8-X]

SMASHEK: I still haven't been able to locate the problem with my X. It's been a year and 3 months that I've had the problem.

No Ford Service Center has been able to find the problem. They state it runs like a normal X should.

Independent shops can't find anything either, as all the shops I've contacted state they will be unable to find the problem without the CEL on.

Of course I haven't had the CEL come on since the #4 plug went out. Which is when this problem started.

Hopefully you'll be able to determine what the problem is and get it fixed for a reasonable price.

If you locate the problem, let us know if you could. Most likely it'll mean I'll replace another part that does not fix the problem.

 

[SMASHEK]

Replaced the plugs

Thanks for the reply. The truck has 67000 miles so I changed the plugs. Inspecting them I saw no signs of fouling. The problem seemed to go away, but no dice. Did you ever change your vehicle speed sensor? I was thinking about trying this because it went out on my Ranger. The strange thing about this is that I do not get a check light. Well I'll try some other stuff in the mean time.

 

[V8-X]

I have not replaced the Speed Sensor as of yet. This was a part I was curious about, but didn't know the effects that a bad VSS would have while driving.

I have had Rangers before and never had a problem with the VSS, but I have heard of many Rangers with this problem.

Like you, the CEL does not come on. I would think a bad VSS would trip the ECC and set a code.

Let us know what you try and if it works or not.

 

[fordkrazy]

well it would if the computer got no signal or an unexpected signal.....remember....hall effect sensors dont neccessarily create codes when they are bad

if the sensor gives an improper signal for the given driving conditions it will cause a problem but the computer only looks for a "range" of signal....so the computer bases its calibration on that signals input

the VSS is exceptionaly affected by this because there is no other system to confirm that signal the computer is recieving is correct.....the cam position, crank position have other systems within the engine control that confirm the signals

sounds like a good plan to replace that if its not to expensive......however...im not sure if the speedo uses the same sensor but if your spedo is reading right im sure the sensor is fine unless there are 2 seperate sensors

 

[V8-X]

I had done some research a while back and found out that:

Yes the Speedo uses a seperate sensor then the VSS. Still my Speedo is about 4-5mph over what it should read. (Reads 45mph when traveling 40mph).

So the VSS could have a problem without effecting the Speedo.

The VSS isn't to expensive so I might looking at replacing it anyways. I beleive it is located in the rear diff on my X, but is in the Trans on older model X's.

If/When I replace this, I'll let everyone know if this fixed the problem.

 

[V8-X]

Checking again, the VSS does control the Speedo, Per my Haynes manual. Just FYI.

 

[dinas5pt0]

V8-X,

Wife's got almost the same problem w/her 98 5.0 70K miles. Been about a month now. Got plenty of power, just a mis-fire when the engine has a load on it and I'm in O/D & below 1500 rpm. Originally thought it was the tranny. AAMCO took $110 and told me it was not.

If I'm approaching a hill I'll either hit the O/D off switch or punch it enough to get out of O/D and ride 4th @ +-2000rpm

Going into the shop Thurs for a diag and at least new spk plug wires.

Will keep you advised and hopefully turn you into a Caravan killer.

 

[V8-X]

dinas5pt0: Hopefully you only have a fouled plug.

Now are you referring to climbing a good sized hill, or having the problem on any sort of incline?

As I have the problem with any form of incline. You can feel the strain on the engine. You can really feel a vibration though the gas pedal at this time.

Either way, let us know what you come up with.

Still looking for a good deal on the VSS. Want to make sure it's a FoMoCo and not after market. Unless anyone could recommend a good brand VSS I could look into.

 

[tonga3]

V8X,

Have you thought about possibly having a blocked catalytic converter, if they are all carboned up that will definately restrict a ton of power and change the exhaust note. I've seen that before and finally just punched them out and it was a whole new vehicle.