Compression Question

[Randy hamilton]

2006 Dodge Caravan with low miles.
Compression on cylinder #2 (Pass Side front) is 150 cold and 150 hot
Compression on cylinder #4 (middle front) is 135 cold and 150 hot
Compression on cylinder #6 (Driver side front) is 45 cold and 150 hot.

Car runs great, gets get gas mileage, oil color and texture normal. Coolant is normal.

What do you think. Normal?

Topic

[Randy hamilton]

Cyl #1 – 150 Engine Warm
Cyl #3 – 150 Engine Warm
Cyl #5 – 153 Engine Warm (rear driver side) not tested hot

Doesn’t seem to be consuming oil or water

[Randy hamilton]

Compression tested ~150 psi on all cylinders today (cold)

Unclear why the low reading several days ago. Perhaps a sticking valve or ring.

[hondaguy453]

Hello, Randy! Did you have a P0306 and that’s why you tested compression, or were you checking for your own peace of mind? As you mentioned, it could have been a sticky valve which usually stems from carbon buildup. You can try using some seafoam to clean the carbon out.

[EricTheCarGuy]

Compression test really don’t tell you much. A leak down test is much more informative in my view. I only do compression tests when looking for a dead cylinder. If you don’t have a misfire, or any codes, and the engine runs fine, you’re probably fine. The discrepancies are likely due to testing errors.

[Randy hamilton]

Thanks.
I just drove the vehicle on a 2000 mile road trip with no issues. Gas mileage as expected or slightly better for a V6 and a loaded vehicle at approximately 4600lb gross.
Seems to have been a testing failure rather than an engine component failure.

[EricTheCarGuy]

Thank you for the update. Glad it worked out.

[Author]

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