When accelerating at full throttle, at around 4-5,000 RPM the truck hesitates. I'm pretty sure a cylinder isn't firing. But it only happens under acceleration at higher RPMs.

I'm going to start investigating the problem this weekend, anyone have suggestions on where to start? Just last year I replaced the ignition module along with the plugs and wires. From reading some older posts my guess would be the fuel filter or MAF sensor.

-Levino

 

My 4.0 sometimes does that....almost like it has a lack of power. I'll be watching this thread.

 

mine does the same thing, but only in second or third gear im not sure which. but it happens at that rpm and like 45-50 mph. so whatever gear that might be....

 

I poked around the ignition system and found nothing wrong.

But the computer began throwing 2 codes, 1. Camshaft position sensor malfunction and 2. Cylinder misfire. I'm sure they are related. From reading on here, the camshaft sensor malfunction can cause the engine to misfire at high rpms, so I have a target now

I just replaced the sensor and it still doesn't run right. So tomorrow I'm going to try and replace the camshaft synchronizer.

-Levino

 

I have the exact same problem with my 99 3.0, it threw the camshaft sensor code first and i had it replaced, then it threw the cylinder misfire code

one of our family friends is a mechanic with ford connections, so i had it all fixed through him, so far i have replaced the camshaft sensor, plugs, wires and it still throws the code, so we think it may have something to do with the computer being faulty, but i've been running it with the CEL on for a couple months now and havent had much problems, other than it seeming to lack power from time to time

just an FYI, the sensor is no cheap fix, around $500, i got sick of throwing money away and not solving the problem, so ive been looking for a used computer for a while to see if that will fix the problem

best of luck to you solving this problem, hope i've helped

 

I got it on my 98.... Must be a 3.0 thing.

Mine throws the missfire code cant remember if it does the cam tho. I just ride with the engine light on.

 

is revving the truck to 4-5k good?

wow, i shift at 2k in my 3.slow. i could not imagine revving her up to 5k

 

Thanks guys, I'll let you all know if I come up with anything.


My truck makes maximum horsepower at 4700 RPM (said consumer reports in 2000), so hitting 4-5K never bothered me......also I have a heavy foot

-Levino

 

If you floor it with a auto trans then it lets it rev up to higher rpms.

Mine actually has bounced off the limiter a couple times, but my trans is also on its last leg so that could have a little to do with it.

 

Man thats crazy mine does the same thing! It will be pulling so hard then I think its either 2nd or 3rd gear around 4-5 grand she kind of takes a breath for a second then keeps pulling
Its wierd as heck!

 

Good news. My check engine light went away. So it seems replacing the sensor fixed my problem. After driving for a couple days, I noticed I got my power back when I start from a stop. I also haven't noticed any hesitation yet, but I am trying to keep the RPM lower anyway.

FYI, I heard somewhere that the computers in vehicles will show codes for a couple days after the problem goes away. There is a delay for some weird reason. That's why I decided to wait before I keep buying more parts.

-Levino

 

It sounds like the governer is kicking in. in park my truck if i rev the engine up past 3000 r.p.m it kicks in. In drive around 90 t0 95 m.ph again it kicks in. I have never rev'ed the to 4000 or 5000 in 1 and 2 gear so who knows.

 

Man I can't get mine to bounce, I think I have one time..but barely! haha.

I usually let it shift around 3-4k mines auto..when my foot goes down hard it shifts at about 5-55k...

I haven't had this problem with my 3.0..I haave 40k on mine.

 

Many 3.0's are air starved at high RPM. MAF mod, throttle body mod, and a free-flow filter got my high RPM power back.

But it sounds like we may be talking about different things here causing the same symptoms. Mine never threw codes -- it just wanted to breathe!