Q: RPM drops while driving

asked by on

I recently did some work on my truck, new fuel filter, oil, oil filter, valve cover gaskets, spark plug tube gaskets, intake mainfold gaskets, MAF sensor cleaned, throttle body cleaned, and cleaned some dust and dirt off the air filter. About a week ago it started to drop rpm while I drive once i get to speed and the rpms come to the normal 1500-1600. They drop down to 1000-1100 and i can feel it aswell as watch the rpm gauge drop. I am getting no DTC codes or check engine light. I am stuck and have no idea what to check next. Maybe PCV valve? Thanks for any help!

My car has 170000 miles.
My car has an automatic transmission.

Hello, from what you describe it appears that your vehicle may be experiencing some sort of engine performance issue, perhaps a misfire. Usually misfires will cause a drop in rpm, as well as shaking or engine vibrations. This can be caused by many things. If you recently worked on the vehicle, I would go back and double check that all sensors and connectors are properly secured and in good condition. Specifically any that you may have worked on. The next thing I would do is check for vacuum leaks, perhaps through damaged hoses or faulty gaskets. The PCV valve may also cause similar symptoms, if it gets stuck in the open position. If it remains stuck open the engine will have a vacuum leak, which can cause misfires. I would start by double checking all the components you worked on, and then going from there.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. RPM drops while driving

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: Would the crankshaft be the issue for the car losing power or misfiring gears?

Hi! It sounds like there are a number of things that could be going on with your Mountaineer. If you feel like it's in neutral when you're in drive, that is a transmission issue. You can start by checking the...

Q: ABS/VDC/Slip light on.

Hello. If these lights were not on prior to replacing these parts then you need to start by checking the brake fluid. Low brake fluid or a bad brake fluid level sensor will cause this problem. If the fluid and...

Q: Chevy equinox won't move out of drive way.

Hi there. First check the transmission fluid and make sure that it's full and red in color. If the fluid is full, then the issue could be either the transmission valve body (module) has debris inside it causing the circuits...

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 Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.