My 2003 Toyota Echo often hesitates while accelerating or cruising as if there was an interruption in fuel flow or a problem with the ignition. On one occasion, the engine stalled completely and the "check engine" light came on. The engine restarted easily enough, and when I drove on, the problem seemed to correct itself. The "check engine" light remained on for the remainder of that day, but did not come on when I restarted the following day. The problem of engine hesitation persists, but it is very inconsistent and the "check engine" light has not reactivated. It may behave normally for several days, but eventually the problem recurs. Often, the engine hesitation is severe enough to produce a jerking or bucking motion to the car and this may persist for a minute or two, but eventually, it settles down and returns to normal. A Toyota mechanic checked the ignition system and also checked the fuel tank for contamination. I presume he also checked the fuel filter, but did not replace it. He concluded that the problem was caused by a faulty throttle sensor and replaced it with a new part. Unfortunately, my problem with engine hesitation continues. Any ideas?

Possible fuel problems. Dirty fuel filter or injectors....this can also be an ignition problem. If any codes showing up have them checked at any Autozone for free

Reasons for poor acceleration:
- Ensure that there is sufficient fuel in the fuel tank.
- Mass Air Flow sensor.
- Fuel system.
- Ignition system.
- Idle speed control valve learning is incomplete.

Sir, your question is not very clear, but I will still try to post a solution here. Engine missing could be due to any problem in fuel system, ignition system, engine or ECM as well.

LOW ENGINE IDLE SPEED (Poor idling):
-Throttle body (do the cleaning and idle speed learning)
-A /C signal circuit
-Fuel pump control circuit
-Fuel pump
-Intake system
-P C V valve (clogged or open) and hose

ROUGH IDLING:
-Cylinder Compression
-Ignition system (Igniters, spark plugs, wiring harness)
-Spark plug fouled, gap too wide or too short. (1.00-1.1 mm)
-Fuel injector circuit
-E C M power source circuit
-Fuel pump control circuit
-Fuel pump (required pressure 44 psi - 49 psi)
-Throttle body (cleaning)
-Intake system
-P C V valve and hose
-Air fuel ratio sensor
-Heated oxygen s ens or
-Mass air flow meter
-Idle hunting
-Throttle body
-Intake system
-P C V valve and hose
-Air fuel ratio sensor
-Mass air flow meter

HESITATION/ POOR ACCELERATION:
-Fuel pump control circuit
-Fuel pump
-Spark plug
-Ignition system
-Fuel injector circuit
-E C M power source circuit
-Mass air flow meter
-Throttle body (do cleaning)
-Intake system
-Valve timing
-Cylinder Compression

ENGINE HESITATES WHILE ACCELERATION

LOSS OF ACCELERATION

It can be fuel pressure issue or it's the problem with accelerator pedal or its clogged filters causing there.

There are many other possibilities. I suggest you to go through the list of help links mentioned below, these will help you to confirm where the actual fault lies: -------

Jerks and Hesitates During Acceleration?

http://technoanswers.blogspot.in/2012/07/2004-dodge-town-country-jerks-and.html

-----------

Loss of acceleration?

http://technoanswers.blogspot.in/2012/02/loss-of-acceleration.html

---------

Headlights flickering and car hesitates to start?

http://howtobyme.blogspot.in/2012/02/headlights-flickering-and-car-hesitates.html

--------

How exactly the Vehicles Accelerator Cable works?

http://repairhelpcenter.blogspot.com/2011/11/how-exactly-vehicles-accelerator-cable.html

-------------

How exactly Vehicles Accelerator Pump Diaphragm Works?

http://repairhelpcenter.blogspot.com/2011/11/how-exactly-vehicles-accelerator-pump.html

--------

2000 Toyota Avalon: Engine Lean Codes and Knock Sound on Acceleration?

http://whatisbyme.blogspot.in/2012/05/2000-toyota-avalon-engine-lean-codes.html

---------

2004 Toyota Avensis: Acceleration And Deceleration makes noise on Front End?

http://whatisbyme.blogspot.in/2012/05/2004-toyota-avensis-acceleration-and.html

---------

Wheel hop under hard acceleration?

http://technoanswers.blogspot.in/2012/04/wheel-hop-under-hard-acceleration.html

--------

2009 Chevy impala accelerator pedal sensor?

http://technoanswers.blogspot.in/2012/02/2009-chevy-impala-accelerator-pedal.html

---------

Nissan Pathfinder stalls and bucks on Acceleration?

http://technoanswers.blogspot.in/2012/02/nissan-pathfinder-stalls-and-bucks-on.html

--------

Acceleration lag problem?

http://repairhelpcenter.blogspot.com/2012/01/acceleration-lag-problem.html

-------------

These details will help.

Thanks.

ENGINE HESITATES WHILE ACCELERATION

LOSS OF ACCELERATION

It can be fuel pressure issue or it's the problem with accelerator pedal or its clogged filters causing there.

There are many other possibilities. I suggest you to go through the list of help links mentioned below, these will help you to confirm where the actual fault lies: -------

Jerks and Hesitates During Acceleration?

http://technoanswers.blogspot.in/2012/07/2004-dodge-town-country-jerks-and.html

-----------

Loss of acceleration?

http://technoanswers.blogspot.in/2012/02/loss-of-acceleration.html

---------

Headlights flickering and car hesitates to start?

http://howtobyme.blogspot.in/2012/02/headlights-flickering-and-car-hesitates.html

--------

How exactly the Vehicles Accelerator Cable works?

http://repairhelpcenter.blogspot.com/2011/11/how-exactly-vehicles-accelerator-cable.html

-------------

How exactly Vehicles Accelerator Pump Diaphragm Works?

http://repairhelpcenter.blogspot.com/2011/11/how-exactly-vehicles-accelerator-pump.html

--------

2000 Toyota Avalon: Engine Lean Codes and Knock Sound on Acceleration?

http://whatisbyme.blogspot.in/2012/05/2000-toyota-avalon-engine-lean-codes.html

---------

2004 Toyota Avensis: Acceleration And Deceleration makes noise on Front End?

http://whatisbyme.blogspot.in/2012/05/2004-toyota-avensis-acceleration-and.html

---------

Wheel hop under hard acceleration?

http://technoanswers.blogspot.in/2012/04/wheel-hop-under-hard-acceleration.html

--------

2009 Chevy impala accelerator pedal sensor?

http://technoanswers.blogspot.in/2012/02/2009-chevy-impala-accelerator-pedal.html

---------

Nissan Pathfinder stalls and bucks on Acceleration?

http://technoanswers.blogspot.in/2012/02/nissan-pathfinder-stalls-and-bucks-on.html

--------

Acceleration lag problem?

http://repairhelpcenter.blogspot.com/2012/01/acceleration-lag-problem.html

-------------

These details will help.

Thanks.

ENGINE HESITATES WHILE ACCELERATION

LOSS OF ACCELERATION

It can be fuel pressure issue or it's the problem with accelerator pedal or its clogged filters causing there.

There are many other possibilities. I suggest you to go through the list of help links mentioned below, these will help you to confirm where the actual fault lies: -------

Jerks and Hesitates During Acceleration?

http://technoanswers.blogspot.in/2012/07/2004-dodge-town-country-jerks-and.html

-----------

Loss of acceleration?

http://technoanswers.blogspot.in/2012/02/loss-of-acceleration.html

---------

Headlights flickering and car hesitates to start?

http://howtobyme.blogspot.in/2012/02/headlights-flickering-and-car-hesitates.html

--------

How exactly the Vehicles Accelerator Cable works?

http://repairhelpcenter.blogspot.com/2011/11/how-exactly-vehicles-accelerator-cable.html

-------------

How exactly Vehicles Accelerator Pump Diaphragm Works?

http://repairhelpcenter.blogspot.com/2011/11/how-exactly-vehicles-accelerator-pump.html

--------

2000 Toyota Avalon: Engine Lean Codes and Knock Sound on Acceleration?

http://whatisbyme.blogspot.in/2012/05/2000-toyota-avalon-engine-lean-codes.html

---------

2004 Toyota Avensis: Acceleration And Deceleration makes noise on Front End?

http://whatisbyme.blogspot.in/2012/05/2004-toyota-avensis-acceleration-and.html

---------

Wheel hop under hard acceleration?

http://technoanswers.blogspot.in/2012/04/wheel-hop-under-hard-acceleration.html

--------

2009 Chevy impala accelerator pedal sensor?

http://technoanswers.blogspot.in/2012/02/2009-chevy-impala-accelerator-pedal.html

---------

Nissan Pathfinder stalls and bucks on Acceleration?

http://technoanswers.blogspot.in/2012/02/nissan-pathfinder-stalls-and-bucks-on.html

--------

Acceleration lag problem?

http://repairhelpcenter.blogspot.com/2012/01/acceleration-lag-problem.html

-------------

These details will help.

Thanks.

Look at this thread -seems to be a cure for this problem.

http://www.toyotaownersclub.com/forums/index.php?showtopic=87986

If you own a 2004, 2005, 2006 or 2007 Toyota Corolla and your car hesitates when you accelerate or it hesitates when driving, you should try the solution described here. Below is a list of the behavior your car may show that tells that you should try this procedure before going to a mechanic or repair shop.

• The accelerator is slightly pressed while the car is running and it slightly jitters or hesitates
• After completely stopping the car (a red light for example), it hesitates when you accelerate to continue driving
• Engine power is below the usual level
• Sometimes check engine light turns on

You should know that while those problems can be caused by several issues, including low quality or altered fuel or even a loosely tighten fuel cap, the most common cause is a dirty MAF flow meter sensor.
The MAF sensor (Mass Air Flow Meter Sensor) is in charge of detecting how much air (in mass, not volume) is coming in to the engine, so the ecm computer can calculate the amount of fuel to be injected.
Some times this sensor gets contaminated by lots of microscopic debris that scape the air filter and accumulate on its sensing parts over time. The resulting effect is that the MAF flow meter sensor gets less "sensible" and detects less air than it is currently entering the engine. The reaction of the ecm computer will be to inject less fuel to keep the air fuel balance, taking as reference the false reading of the MAF flow meter sensor. This will produce a too-lean mixture, which is responsible of the hesitation, the loss in power and the check engine light.
If your car engine, besides the hesitation, is also producing knocking or engine pinging at high loads, like when going up through a hill, it is attributed to this too-lean condition.
Before going to an auto parts store or to a mechanic to fix the problem, you should try fixing it your self. If the problem is a dirty MAF flow meter sensor, the solution is to clean it, plain and simple. That may save you some money that a mechanic will charge for cleaning it (you could do the same) or for replacing the part when most of the times it is not damaged, just dirty or contaminated

It can be a few things that cause this.Mass air flow sensor,Map sensor,clogged fuel filter,timing not correct(cause by the knock sensor).I would replace the fuel filter first.Thats the cheapest thing.If problem still exists.Go to a local AutoZone or Pepboys and have them scan for a bad sensor code.Its FREE.Then replace what ever sensor is the problem

its located inside fuel tank