2001 Rodeo 3.2 "Bucking" on acceleration

Hi. I have a 2001 Rodeo with the 3.2 V6, 4WD, and the 5 speed manual transmission that is "bucking" upon acceleration. It starts and idles fine, and when I "rev" the engine while the vehicle is sitting still, there are no problems.

As soon as I begin to accelerate however, the engine seems to shut off (tach drops to zero) and all engine power is lost, then the engine regains power almost immediately, begins to accelerate, and then repeats the process over and over. It is also much worse when going uphill.

Another "odd" thing is that the cruise control light on the dash comes on each time it does this, and is accompanied by the little green light on the cruise control on/off switch (next to the 4WD control switch) lights as well, but then both go away after a few seconds, until the engine shuts down again, at which time they both come on again.

The vehicle has 93000 miles on it, and the battery has already been replaced once between about 50000 and 60000 miles. The switch that allows the engine to start only when the clutch pedal is pressed has also already been replaced by the dealer, as has a computer chip that was faulty, both around 25000 miles. I also checked all of the fuses to the left of the steering column as a precautionary measure, but all seem to be fine.

The serpentine belt looks like it could use a replacement, as it is looking worn and cracked.

I suspect either a faulty alternator or the serpentine belt causing the vehicle to not have enough electrical load under acceleration, or possibly a loose wire somewhere as the problem. Has anyone here ever had or heard of this problem? I was hoping someone could give me some insight before I go out and buy parts that I don't need, as taking the car to the dealer (or any shop) is a last resort for me since they seem to avoid any problem that would be covered under warranty (10 yrs/120000 miles) until they have already charged you a small fortune to "try" things that don't help.

Any help would be greatly appreciated!

Thanks,
Steve

I would check your battery connections and ground point first.

Then, maybe have the alt load tested.

Unplug the trailer harness (if you have one).

and then finally I would have the Intake manifold gasket replace (warranty issue).

Have you ever cleaner the egr or throttle body?

Well, the battery connections and ground point are all clean, and seem to be tight....but I will check them again to be sure.

I just replaced the serpentine belt, which was the original belt, and was badly cracked and pulled right off without much resistance. No fix there, although that was something that had to be done anyway.

I am not sure about a trailer harness. Did those come standard? I know I've never pulled a trailer with it, or had any sort of wiring installed by choice to do so, but again, i'll check, and unplug it if there is one from factory.

The egr and throttle body were cleaned once by a dealer, but that was a few years back. If there was clogging there, wouldn't that cause more of a problem that would develop over time? This just suddenly started happening last night, as if something had begun to fail, which I why I assumed maybe the alternator was going bad.

If i cannot find the source of the problem and repair it, the car is scheduled to go into the dealer (ugh) Friday morning....at which time I will ask them to check/replace the Intake Manifold Gasket.

I fear what they might come up as the root of the problem though, as they were very reluctant to just do what I asked them to do in the past, and instead came up with all sorts of things in needed instead....none of which ever did any good of course.

Thanks for the suggestions. I will definitely give them a try.

Have you replaced the fuel filter?

I'm very interested in the resolution of this problem. I have a 2000 Rodeo, 5-speed manual, V6 4wd that has started doing this exact same thing. It mostly seems to happen in 1st or 2nd gear, but I get the same drop in RPM (more like a jolt), and the cruize control light comes on then shuts off. I just took it in to the dealer for its 60k checkup about a month ago. I never had this problem before, and I really don't want to spend more $$ at the dealer if I can avoid it.

The dealer did replace the fuel filter at the check up.

I will certainly post the resolution when I find one.

It sounds like we have the same issue. When the tach drops to zero, then comes back on, the car surges forward and then either accelerates normally for a short time until shutting off again, or just shuts right off again.

I don't believe it is the fuel filter or intake manifold gasket, or anything like that because the car completely loses power (electrical, not just "horsepower") and then comes back on, but has full engine "power" when running normally....almost like if you would turn the key to the "acc" position while driving over and over. The engine would shut off, but the radio would keep playing, etc.

Interesting that you say it mostly does it in first or second gear too. I have sort of noticed the same thing, but really haven't driven it far enough to determine if it does it in the other gears or not....although it seems to do it basically when accelerating, and much worse up hills.

I'll definitely let you know what I find out.

For the small sum of $81 the dealer ran a diagnostic and came up with a faulty power steering switch. They want $67 for the switch and $244 to install it, although I think the $81 diagnostic is included in the $244 total labor, so more like $163 to install it. In any case, it doesn't sound to complicated, and nearly 2 hours of labor seems a little much to install a switch, even if it is a pain in the ass to get at or something....so I suppose I will do it myself. After I do it, I will post weather it fixed the problem or not.

many here will tell you you can just unplug that switch and it will fix itself. You really don't need it. All it does is raise the rpm's when the steering wheel is fully turned one way.

Unplug it for a week and see what you think...

many here will tell you you can just unplug that switch and it will fix itself. You really don't need it. All it does is raise the rpm's when the steering wheel is fully turned one way.

Unplug it for a week and see what you think...

Specifically, do you know where the switch is? Is it on the pump itself, or the reservoir?

Tom.

http://www.automotiveforums.com/vbulletin/showthread.php?t=544286&highlight=steering+switch

read the last post in the trend. The guy that posted is an isuzu tech.

Ok, thanks again for the replies guys. The dealer service shop said when they disconnected the switch the problem was gone. I drove the car home and it was much better, but not completely gone....so I wasn't sure if they reconnected the switch and that was why it was still having problems, or what.

Well, I didn't get time to mess with the car until today.

It appears that the dealer disconnected the switch (and cut the connector right off the wire and left the bared wire just hanging there), as the female end of the connector is empty, and there is no male end anywhere to be found....just a bare black wire that leads up and behind the steering pump to the plug that gets screwed directly in to the pump.

So, not only am i pissed that the dealer would just take the liberty to cut things off of the vehicle (yes, i know the connector comes with the new switch, but it still doesn't make me too happy...not that I was happy with this dealer in the first place), but worse is that it seems that unplugging the switch does not completely solve the problem, only makes it better. I can only assume that installing a new switch will not completely fix the problem either.

When I drove it home, it shut off and on only once, when I was going uphill in 1st or 2nd gear. When the girlfriend drove it though (it's her car), she said it drove ok for a while, then started acting as bad as before....and it's been parked since.

Not sure what to do now :banghead:

Well, I decided to just install a new PSP switch, and change the timing belt at the same time since it needed it, and you basically have to remove everything anyway to get the power steering pump off to change the PSP switch....and I'm a little stumped on how to remove the drive belt tensioner (not the timing belt tensioner....haven't gotten that far yet).

Everything else is off, including the pain in the butt crank pulley....but I can't get this stupid thing off. I removed the 2 bolts that seem to hold the housing in place, but no dice....and the Haynes manual I have isn't much help.

Just wondering if anyone knew how to get this thing off.

Thanks!