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.

A: Hi there, thanks for writing in. You should...

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

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Check Engine Light stays on.

Hi there You should have the computer Check Engine Light scanned by a mechanic. Once the codes are received and the pinpoint test is completed, you should have a diagnosis of the failed component. A lot of times a code...

Q: Car engine shakes when in idle or Drive

Hello. I am assuming that your motor mounts are collapsed since there is no Check Engine Light on.

Q: My Cadillac Seville does not stay on after I start it

This is likely related to a fuel supply issue due to the fact that it requires starter fluid to stay running. I would begin by checking the fuel pressure after replacing the fuel pump to be sure it is getting...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...