Skip the auto shop - Our mechanics make house calls

Q: loss of power. 2003 Mazda 6

asked by on

Ok I have a 2003 Mazda 6 2.3L and I just rebuild the engine and after having spun rod bearing. Had the crank truned and posihed. so basicly long story short everything is new and been build right. My problem is that when I started it the car ran prefect and smoother than it had ever been. It ran good for about a week to week and half and had all kinds of power and ran really good and quick for what it was. Then about the 2nd week it has lost power and will not hardly take off. The think its tricky is that after you get it go it will pick up speed and I can get up to over 100mph if I wanted. But it still doesn't have the power it should. I have tryed everything I know to try. Not bragging on myself but I am ase certified and pretty smart on cars and it has me stumped. I have checked compression and its good with 125-130psi. Fuel pressure is 55-65psi. I have put o2 sensors on it. I have tried MAF, Coil, pulgs, Egr. I have pulled the intake back off to check it to make sure I didn't miss

My car has 150000 miles.
My car has a manual transmission.

Hi there, thanks for writing in. You should check to see if the timing belt is off or jumped, or your injectors have some blockage and needs to be cleaned cleaned. Also, make sure you have a clean fuel filter. If you still have low take off power, then see if the vehicle revs in neutral without hesitation, then check for excessive back pressure from the exhaust catalyst.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Oil light flickers when come to stpp. Light or stop sign

Hi there. It's likely that either your engine oil level is low or you have a problem with the oil pressure sensor that is causing this issue. I would start by checking your engine oil level or having the oil...

Q: Fuel pump problem

Hello. Code P0089 is the code for an issue withe the vehicle's fuel pressure regulator. In this instance it appears that the code refers the fuel pressure regulator mounted in the engine bay, on the vehicle's high pressure fuel pump....

Q: I need to isolate my intake from the PCV system

Hello. A high end catch can with a substantial stainless baffle will catch the oil vapors, as well as water, so there is no reason it or indeed sequential cans if you want to improve oil removal efficiency can't be...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.