Q: loss of power. 2003 Mazda 6

asked by on August 30, 2016

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.

Timing Belt Replacement $295.56 - $1284.62 Get a Quote
Fuel Injector Replacement $379.42 - $3631.88 Get a Quote
Fuel Filter Replacement $83.13 - $270.56 Get a Quote

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.

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・Fair and transparent pricing

What others are asking

Car broke down after making knocking sound.

This sounds like a possible loss of oil problem. If the engine has seized up before and the problem is reoccurring the engine is most likely dry. I would recommend checking the engine oil to see if it is low....

Jeep starts fine but then won’t move. Only rev. Only happens when it sits overnight. I have a Jeep Wrangler, 112000 miles

Hi Meagan. Thanks for contacting us today. Usually when you can shift into reverse, but the car will not go forward in drive, then it's caused by a damaged shift solenoid or internal transmission problems. An obstruction of debris inside...

check engine light came on for about a week then went off for a couple of days and now has returned

Hi there: Looks like you've got two separate issues and questions here. First, if the check engine light came on, vanished and returned again, that's typically an indicator that the ECU (engine control unit) registered an error code or trouble...

A mechanic at sears auto center told me I had a oil pan leak. But i have not seen any oil leak from under my car. He recommende

Oil leaks should be repaired because leaking oil can damage external engine components such as rubber motor mounts. If you want the source of the oil leak identified and the repair estimated, simply request an oil leak diagnostic. Your vehicle...

2003 camry ac circuit needs replacement

Hi There, Depending on what your mechanic was referring to with respect to the AC system, there are a number of possibilities that may cause problems within the A/C system. Several components make up the entire "A/C circuit." The locking...

Electrical power steering pump doesnt work after car wash

You may have got water into the connections causing the problem. You will need to disconnect electrical connections on the electrical steering and blow out connections with compressed air and see if this helps? If the system has a power...

Cars runs rough and sluggish upon cold start

Hello. It is not normal for the car to run rough when it is cold. This could be a sign that the car needs a tune-up and may also need a fuel system flush. The spark plugs, and ignition coils...

Whole Car shakes while driving

It sounds like you may have a failing or worn out wheel bearing. A wheel bearing will usually fail due to pitting or small damage on the surface of the rollers or the bearing race. Both the surface of the...

Vehicle shutting off after a loud squeal.

Based on your description I believe you could be having one of two things happening. One explanation of your squealing noise could be a slipping serpentine belt. This belt drives all the accessories attached to your engine such as your...

Related articles

Symptoms of a Bad or Failing Automatic Timing Advance Unit
If your car experiences engine knock, sluggish performance, or excessive black smoke, you may need to replace your automatic timing advance unit.
How to Diagnose a No-Spark or Loss of Power Condition on a Modern Car
Misfires caused by a loss of power condition on a car can be tricky to diagnose, but are necessary to fix to avoid further damage and costly repairs.
A Buyer’s Guide to the 2009 Mazda Tribute Hybrid
2009 2009 marked the end of the very short life of the Mazda Tribute Hybrid. All told, the automaker produced fewer than 700 models, and it was ultimately retired well before the Tribute itself ceased production in 2011. For the...