Q: Hesitation occasional misfire and poor mpg

asked by on July 10, 2017

Had a very long cranking time to start idled very rough and had poor power/acceleration. occasionally when I first start the car there is almost zero power even with the peddle to the floor and it will backfire a few times. But not a normal back fire it sounds a lot quieter, and comes from the front of the vehicle inside the engine bay. After a few pumps of the peddle it's like it never happened and the rest of the drive the car runs normally. I changed the fuel filter and it smoothed out the idle. I opened to intake plenum, back two cylanders we're washed clean, so I replaced the fuel pressure regulator. solved the long cranking. Now the hesitation/power/poor fuel economy problem. So far replaced worn dist cap and rotorand map sensor also plugs and wires. Got a touch better. Then unplugged the maf and got a little power and acceleration back. So bad maf? Or something else being masked running in open loop?

My car has 150000 miles.
My car has an automatic transmission.

The MAF is a possibility. I think it is also possible that one or more injectors are clogged or malfunctioning as the symptoms you describe sound like that of a fuel system issue. I would recommend having the fuel injectors and mass air flow sensor tested with a digital multimeter to determine if they are within the manufacturer’s specifications. If not, replace any parts that fail to meet specifications.

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

I actually have a problem with my Motorcycle Fuel Injection system; it seems that its not getting enough power to pass the fuel; would you be able to help?

Car squeaking noise at rear after brake change.

The suspension is unloaded, and thus out of it's usual running position, when the weight is off the springs. It's possible that a rubber isolator moved or some like change occurred as the car was in the air and while...

Where is my starter on my 98 Honda Acura 3.2 Tl

Hi there. You might want to watch this video on replacing the starter on a similar 3.2 liter V-6 on a 2003 Acura - which has the starter located the same as your 98. If you determine that you'd rather...

Hit a curb, bent the axle?

Although the CV axle on the side that was hit, particularly the CV joints, could have been damaged in the collision, the damage you are seeing is more likely due to the control arm, strut, and steering knuckle getting pushed...

Overheated, power steering went out and battery went low

Hi There, What you have described sounds like your serpentine belt may have come off. As you may know all of the accessories (ie alternator which charges the battery, power steering and the water pump) are driven by the serpentine...

Exhaust smell in cabin while idling

Since you just had major engine repairs done and the exhaust system was disconnected and the manifolds were removed then you may have an exhaust leaking into the interior. You should have the a/c on recirculate air and not outside...

Car loses some engine power when the blower is turned on.

A minor loss of power when the fan is engaged is probably due to the air conditioning compressor. When the air conditioning, or the heater, is switched on, it activates the compressor. The light squeal is most likely coming from...

Steering issues, my car does not turn well

The power steering system may have a leaking return hose from the steering rack and pinion to the return reservoir. This leak can cause the power steering pump to suck in air into the steering system and cause noise and...

My upper radiator hose is pinched in and there's no flow to the reservoir bottle

Hello - it is possible that the pinched radiator hose (wrong hose?) is interfering with the engine drawing additional coolant between hot/cold cycles. If it were me, I would drain the coolant - you need to do that to put...

Related articles

The Best Used Cars to Buy If You're a Carpenter
If If you're a carpenter, and working for someone else, the best used car is whatever you like that gets you to work on time and holds your tools – in short, practically any used car will do. If you...
2012 Toyota Camry vs. 2012 Chevrolet Malibu: Which One Should I Buy?
Mid-size sedans are the perfect family vehicle; offering just enough space for you and a few kids, but not so much that a small family will feel lost in them. This class of vehicles is slightly larger than a compact...
The Top 5 Selling Cars in Georgia in 2012
Georgia Georgia offers drivers a mild climate with very little snow, but rain is a major factor. Previous best-selling cars in the area, such as the Escape, Fusion and Camry, have shown that residents prefer a mix of both SUV...