Q: Found out 1st cylinder in car has no compression....what are my options?

asked by on

Engine light came on one day after not driving vehicle for a week. Took it to Meineke who did compression check and found first cylinder has no compression all others are fine. Question is what are my options as far as fixing my vehicle. codes that came from diagnostic tool is P0300-0302 and p0171 for gas mixture too lean

The first thing you have to do is confirm such a diagnosis by getting a second opinion. It is unusual for three cylinders to be perfectly normal and one to have "no" compression. Nevertheless, it is possible.

A cylinder can fail to seal and then fail to develop compression due to the following defects: 1) a leaking head gasket; 2) a stuck valve; 3) a burnt valve; 4) a damaged valve seat; 5) a piston ring issue; 5) an engine timing belt mispositioned (unlikely if 3 cylinders are good).

All of these defects require possible but substantial repairs. You first have to confirm that you indeed have low compression unless you are very, very confident that all test were done competently. Mechanics are like medical doctors, they can make mistakes even with the best of intentions. To have the correct fixes pinpointed, have a second expert, like one from YourMechanic, come to your car’s location to inspect the Check Engine Light codes in more depth and help you with a repair.

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. Found out 1st cylinder in car has no compression....what are my options?

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: P0301

Diagnostic Trouble Code P0301 means that Cylinder No. 1 is misfiring but the causes of that can be very varied. The fuel injector could simply be dead or there is little cylinder compression due to a burned valve or leaky...

Q: Transmission grinding when in gear.

Differential failure is a likely cause of this symptom. A faulty CV axle or transmission failure are also likely causes. I would recommend having your transmission and differential inspected by a professional to ensure all parts are working correctly.

Q: Car is running slow, what could it be?

If you already replaced the sensor then now it will need that connector you've mentioned. Replacing it may fix the code P0502. The code P1406 is for the EGR valve position, you would need to have the valve tested to...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...