Skip the auto shop - Our mechanics make house calls

Q: Car is misfiring and has a lack of power

asked by on

So i just put in a used motor. Pretty much everything is new. When its cold started it idles at 1,000 rpm and dosnt go down until u shift into reverse or drive. When u step on the Gas the rpms drop and chugs and finaly starts moving. I set timing and spark plugs are in order. There is no vaccum leaks.
My car has an automatic transmission.

A: It is very difficult to definitively say wh...

It is very difficult to definitively say what the issue is. Have you had the vehicle scanned for diagnostic troubleshooting codes? If not, you should start there. Due to your vehicle being pre-1996, the method of receiving codes will be more difficult. You should look to your owners manual for that procedure. Hopefully, the issue will have set a code and will make diagnosis a lot easier.

If this is a misfire, its likely a code is pending. Chances are, this is a problem relating to the air fuel mixture entering the engine when the vacuum changes after entering a gear. If you are certain there are no issues with the vacuum, look to the throttle body, fuel injectors, and valves.

If you need some assistance with these checks, consider YourMechanic, as one of our mobile technicians can come to your home to diagnose the misfire firsthand and help you fix it accordingly.

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: can i drive my car home from work when i found out i had a misfiring cylinder this morning?

A misfire can be caused by several components and if you should drive it depends on the issue that is occurring. Most likely if you made it to work without any major issues, you can make it back home. It...

Q: When I accelerate it has no power. It only goes slowly. I have a code PO700 that has came up.

Hello. Code P0700 is the trouble code for an issue with the vehicle's transmission control system. If the computer detects an issue within the transmission control system it will set off the Check Engine Light in order to alert the...

Q: Want to put dual exhaust on, but not sure if that's going to mess with my computer.

Hi there. Although we typically don't offer mechanical tips on aftermarket upgrades, in this case, you are correct to be concerned about how the OEM computer is going to 'react' to the exhaust upgrade. In most cases, the system that...

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...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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...