Oil cap fell off while driving

SHALLEM GREEN

MEMBER
2000 PLYMOUTH NEON
236,935 MILES

Oil cap fell off while driving car stopped. So I walked and went and got a new one I put about two quarts in it take me to the car wash degrease the engine pressure wash the engine take me to Jiffy Lube got a oil change. The car still has trouble staying started and it is running really rough. I had to pull over but it starts back up but it runs really rough. What is the problem please?

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,747 POSTS

Hi and thanks for using 2CarPros.

Honestly, chances are the mess that was made is not the problem, but rather, if you sprayed the engine and ignition system with high pressure water, something got wet and has shorted.

First, is the check engine light staying on while the engine is running? If so, have the computer scanned for trouble codes. That may point us at a specific cylinder misfire.

https://youtu.be/YV3TRZwer8k

Next, check for engine vacuum leaks that may have been caused by cleaning and the high pressure water. Here is a link that describes how to check for leaks:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

I have a feeling it is either a coil or ignition component or a vacuum leak. I realize most people do not own a scanner. However, most parts stores will scan it for free. Have that done if the light is on and let me know what code is found. In most cases, I can even tell you if the problem is a vacuum leak based on the code. Also, it may point to a specific cylinder misfire.

Take care and let me know what you find.

Joe