The last 4 months my car has been hesitating with check engine light on.I took it to Auto Zone and 2 codes came up to replace the air intake sensor and knock sensor. Now it doesn't happen consistently,some days are worse then others whether the car is warm or cold.Between 1500-1800 rpms the car starts chugging after 50 mph it smoothes itself out. Replaced the air intake sensor at a mechanics garage but not the knock sensor, and it is still doing the same thing but check engine light is off now. Mechanics I have spoke with said there is nothing they can do because the engine light is off. They said if its your fuel injectors you won't get a check engine light. What could be causing this?
Car hesitates but no check engine light on on 2000 Infiniti Q45
by dameculotte in West Bloomfield, MI on April 11, 2011
ANSWER by woodward auto , April 29, 2011
I would take a look at the boot for the mass air flow sensor, you can still have the injectors tested and also cleaned with a BG fuel induction service.