pause or hesitation
 

Recently i have noticed that when sitting at a stop light with your foot on the brake the car feels like it wants to slightly jump forward. (sorry tough to explain) also noticed when driving up a hill sometimes the car feels like it loses power for a split second, but when driving on flat grade that problem never arises.

Any ideas?

02 3.4L

Can you see changes in the rpms when these things are happening?

How many miles? On spark plugs? Fuel pump?

RPms jump slightly, but not much. Car has 230,000 Kilometers, not sure what that is in Miles?

I changed the plugs and wires 1 year ago, also fuel pump went a year ago, so the fuel pump is only 1 year old as well.

Throttle position sensor?

Sorry, i have no idea, what or where it is?

Maybe a Haynes or Chiltons would have a drawing. I think it's on the end of the shaft that the throttle plate swings on (in the air intake).

There are various other sensors that can cause problems like your's. Camshaft Position Sensor and MAP among others. Some may set a code for the scan reader, others won't. May be time for a mechanic with the proper test equipment, rather than guessing and throwing parts at it.

I had a hole in the vac line feeding my MAP that did this stuff, only 100x worse. Yours could be slightly cracked. For the whole $0.23 it cost to get a new one, you migh just want to replace it.

Also, under load, like climbing a hill in high gear, does the engine seem to fall on its face, then catch up and pull strong, then repeat the cycle? That kind of surging is usually a lazy oxygen sensor. I had one on my truck become lazy enough to make it run like absolute crap, but the PCM never threw a code for it. Yours could be slightly lazy, and not causing major issues yet. A bad o2 sensor can also cause a bad idle.

I wouldn't just go and change the sensor now though. If it is bad, it will become obvious pretty soon.

Where is the vac line that feeds the MAp located?

Its under the map sensor. Comes right out of the upper intake into the map. Its really short. There are two screws that hold the map onto the braket, I think the are 6 or 7mm maybe smaller.

I will take a look at my hanes manual, I have no idea were the MAP is or what it looks like.

Does the Hanes manual have another name for the MAP?

Manifold Absolute Pressure sensor. If I can find a picture I will post it up for you.

That would help, thanks Rusty

I'm having the same issue. However, my check engine light is on, steady, and I found out it is the second o2 sensor. It will be replaced sometime hopefully this weekend. I will come back and post whether it fixed the problem. Also, did you figure out your humming noise? Was it the bearing? I only ask because I am having major issues with mine, have had bearings replaced 3 times in past year and a half. Car makes noise when accelerating, especially at higher speeds (highway and such), dont laugh but it almost sounds like theres a helicopter flying above me!
So glad to have found this forum. I have had nothing but problems with this car since purchasing. Even had to replace engine already.

yes it sounds like your bearing. the best way to figure out which one is bad, jack up the front of your car so both front tires are off the ground. block off your back 2 tires so the car doesn't roll on you and put your car in Neutral.

Now go to the right front tire, and reach on top and grab the spring with one hand and spin your tire with the other, then do the same for the other side. The tire with the bad bearing will give off lots of vibration through the spring.

Brought vehicle to the mechanic, apparently the wheel bearings are fine. Told me that it is actually my transaxle bearing? the left side has some play in it, while the right side doesn't move.
Anyone ever have any issues with this? It's going back into the shop on Monday.
Thank you wut for your suggestions and response! :)

Try starting a new thread with "Transaxle bearing" in the title.