I have a 03 mazda 6 that the accelerator will surge up to about 3500 rpm and will not idle down when stopping at a light. It starts doing this after running about 20 minutes. If I kill the engine and restart it, it runs fine for a while. Do I need to replace a sensor or fuel filter or what?

francisco navarro

• 241 Answers
• Posted on Jul 09, 2008

SOURCE: mY car is a 1995

check your air mass meter or map sensor

Marvin

• 85242 Answers
• Posted on Nov 10, 2008

SOURCE: wants to stall at idle.

Here is the most common cause of this stall, it is the idle speed control air-bypass valve and throttle valve, they get full of gunk over the miles and cause idle issues (stalls) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.

SOURCE: rough idle / engine surges until power is applied

Sounds like a possible vaccume hose leak?

SOURCE: engine surging , won't accelerate over 3000 rpm ! IS chocking is like is not enogh gas

Do you have a check engine light with this?
What can happen is a code has caused the engine to protect itself. For example in a low coolant situation when the engine heats up too much, the engine can Knock causing an Engine Knock fault.
If that occurs you will recieve a fault for each of these items. Fill the engine with coolant. Then reseting the code will let your engine accelerate normally.

SOURCE: poor acceleration while trying to pass and check engine light on

You said it struggles between 2500 and 3000 RPM. checking the hose for vaccuum at idle won't work. Rev the engine to the problem RPMs and check. That will tell you about vaccuum. As for where it goes, it won't go in the same palce as the brake booster. There will be another connector. If the re is a T there now, it sounds like someone else may have changed things around.