Hello Everyone!

Here's the issue with my 2000 Ranger XLT w/3.0 V6.....~143,000 MILES

Engine runs like a well-oiled sewing machine under 3500RPM, but when truck is stationary in neutral, revving the engine above 3500 - 4000 RPM causes violent engine shaking and bucking....really bad. It's as if one of the cylinder banks just quits, causing bad physical imbalance. I'm sure the same thing is happening when cruising and I try to rev it over 4K, but the shaking is dampened then because the vehicle is in gear and moving.

CE light came on months ago, but that was/is intermittent. It did throw some codes I can't remember, but I believe they were "P0xxx" codes relating to 02 sensors. Unfortunately, the battery died recently, and when installing a new one, the codes got cleared. Once everything resets itself after some drive cycles, I'll use the analyzer and read codes again (it shows "pending" codes now).

Anyway.......

One thing I have notice right now is that when this problem is happening, the voltages on ALL the 02 sensors drop to 0, returning to "normal" reading when engine goes back to idle. I thought that is quite strange. If just one O2 sensor did that, I wouldn't be surprised...but all three?

I've search the forum for threads that contained anything like this, but none appear to describe exactly what I am experiencing.

So....any ideas? THANKS!!!!!

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Bobb
Coatesville, PA (Suburban Philadelphia)

2000 Ford Ranger XLT: Stepside Bed, Xtra Cab, 3-liter w/Auto, Tremor Audio Package - Chrome Yellow/Gray

Hello Again. I just took another OBD-II scan and found a pending code "P0153" which is O2 sensor slow response. I figured that a faulty O2 sensor or associated wiring is at fault, maybe even with more than one sensor. I'll be doing the typical searches for vacuum leaks, wire/connector issues, etc.

Standing by for any input anyone can offer. There are a number of threads discussing such issues, but I've seen none that describe the violent bucking over 4,000 RPM that I've been experiencing.

Thanks for any input you can share.

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Bobb
Coatesville, PA (Suburban Philadelphia)

2000 Ford Ranger XLT: Stepside Bed, Xtra Cab, 3-liter w/Auto, Tremor Audio Package - Chrome Yellow/Gray

When in park or neutral I’m pretty sure there is a rev limiter on these vehicle as mine also does this.


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Also my truck would buck and jerk while accelerating hard anywhere from 45mph upwards until I let off the gas then slowly accelerated to speed.

The problem there was a camshaft synchroniser starting to go bad, they usually go out between 80k-100k miles.
Once I had that replaced my truck no longer bucks or jerks under acceleration


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I don't know if you still have the problem, but it sounds exactly like a problem that I had with my 2001 3.0. It took me forever to find the solution.

The problem is with the cam timer, which is located on top of what used to be the distributor. What happens is that the bearings on the distributor drive wear out and allow a lot of end play in the shaft, which starts banging on the cam timer at about 3000 rpm. To fix the problem, you have to replace both the cam timer and the distributor drive. It's not hard to change out the parts.

Thanks bobh45! I appreciate your comment, even though it's been quite a while since my original post. I'm inclined to believe you might be correct. I have heard this information from others as well. Thank you for sharing that info.

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Bobb
Coatesville, PA (Suburban Philadelphia)

2000 Ford Ranger XLT: Stepside Bed, Xtra Cab, 3-liter w/Auto, Tremor Audio Package - Chrome Yellow/Gray

Hello again everyone!

Update on all this....

Replaced defective O2 sensor and there are no MIL/DTCs.

Today I fired-up the truck, and the bad bucking of engine continues when trying to exceed 3K RPM (standing still in neutral). I connected my OBD diagnostic tool and noticed something that I hadn't seen before. When watching "live data" while engine was running, I noticed that FUELSYS1 parameter showed "CL" when running smoothly under 3K, but changed to "OL-DRIVE" when trying to go over 3K RPM. Returns to "CL" at idle.

In the past in this thread, several guys have suggested that the cam timer is bad. Perhaps it is, but that is NOT the FUELSYS1 thing.

I don't want to throw money and labor at replacing parts. I want to diagnose exactly WHAT part to replace (don't we all?).

Ideas anyone? THANKS!

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Bobb
Coatesville, PA (Suburban Philadelphia)

2000 Ford Ranger XLT: Stepside Bed, Xtra Cab, 3-liter w/Auto, Tremor Audio Package - Chrome Yellow/Gray

I had a very similar problem. It was the Camshaft Synchronizer. I don't know if there is a way to test it without having some type of storage oscilloscope.