'01 Camry Hesitates w/ gentle gas applied
 

I am so frustrated, I've always had my car dealer maintained, and now after 3 trips to them, they cannot determine what is wrong with it.

My 2001 Camry LE V6 (146,000 miles) hesitates when the engine is warm after leaving a complete stop and only when low/ gentle gas is applied. It is a very noticeable falter, you can feel the car move back and forth like it is trying to pull away from something holding it back. Even when traveling at 40-50 MPH, when I apply the gas pedal gently just to maintain that speed, I can feel it hesitating.

However, when I take off from a stop with umph or give it steady and strong gas - no faltering. When going 60 MPH and I need to kick-it to murge into the quicker lane to go 80 it does so perfectly as always.

It has never stalled or not wanted to turn-over/start. It idles quietly and smoothly. There is no engine knocking or exhaust fumes.

What the dealer has done to date: cleaned the EFI twice Oct 11 and Mar 12; replaced the fuel filter; replaced the air filter twice Oct 11 and again last week Mar 12; top engine cleaned to include the throttle body; flushed the transmission fluid; repaired transmission cooler line (it was leaking).

The timing belt was replaced in 2009.

I purchased the car new. Other than this issue which only started last Sep, it is a great and reliable car. I hope to have it for another 150,000 miles.

Appreciate any recommendations! :)

The problem only occurs after the engine is warmed up?

What other maintenance has the car had since new such as new spark plugs, etc.

Hi Toyomoho,

It has been well cared for always by the dealership with regular servicing. Last time the spark plugs were replaced was 2008. They were just checked and appeared to be fine. But perhaps it would be worthwhile to have them replaced again.

It has never needed anything significant done to it until the hesitating started. Just the usual oil and filters replaced, brake pads, topped-up fluids, and the timming belt was replaced 2009 when it had about 124,000 miles on it. It now has 146,000.

It iddles smooth, always starts, shifts smooth (automatic transmission) and responds great when I give it hard steady force of gas, and has never stalled.

The hesitation usually starts after I have driven the car several miles then stop for 30-45 minutes. When I drive off slowly with just gentle gas applied it hesitates and continues to do so even tho it shifts into 2nd gear. The hesitation is quite noticeable - feels like it is trying to pull away from something holding it back.

It lets up a bit once I am in 3rd gear but sometimes even then while going 40-50 MPH I can feel it hesitating when I apply just soft - gentle gas in order to maintain that speed.

When I give it umph to get up to 80 MPH on the interstate it is fine. I imagine it is still hesitating at that speed when I apply soft gas to maintain that speed, its just harder to feel it.

Thanks for your help!

If you don't stop for 35-45 minutes the problem does not occur?

Plugs should last 80 to 100K miles, doubt this is the problem.

Every once in a while it will hesitate during the initial start up and drive.... um, like Friday when I picked it up from the dealership's service dept.

I changed where I tank-up a month ago, thinking maybe it was poor quality gasoline (Mobil to Shell). Since purchasing the car, I have always used supreme/premium gas. It got better for 2 weeks, no hesitation, and then it started doing it again.

Last night it hesitated again during the initial start-up. I left work and drove about 5 miles to get some groceries... about 3 blocks from the store it started hesitating - badly. A very dramatic hesitation so much so I thought it would actually stall. It didn't.

However, when I left the store, it was fine. No hesitation at all.

Sigh... very frustrating. :{

May be a problem with the throttle position sensor (TPS) or manifold airflow sensor (MAF).

Both tell the engine computer about how much throttle is being given.

Maybe a failing fuel pump.

The TPS and MAF are both items are monitored by the computer but if not totally failed may not generate a trouble code. The fuel pump is not monitored. All these systems, parts can be tested.

Replacing any of these parts at a dealer will not be cheap.

My advice is find another repair shop, perhaps an independent shop. The dealer does not appear to be doing much. If doing this suggest only providing symptoms along with what was done by the dealer in the past, not recommendations as shops may provide what you request at your expense even if not required.

These parts can be tested electrically.

The owners manual should have the required octane rating needed for the fuel. Typically there is no need to use a fuel with a higher octane rating.

I would also check for any vacuum leaks. Maybe after the engine heats up, a possible leak/gasket leak opens up just enough to cause hesitation.

Thank you SO much Joey & "allcam". I truly appreciate your time and help. I will definitely look for an independent shop, and offer just symptoms and things completed thus far.

I can't continue to pay costs at the dealer, which is like 90% just for labor. :{

Yeah, I would definitely not recommend the dealer. At the same time, make sure you Yelp whichever independent shop you take it to as well.

Sounds good.