2004 5VZ compression test

Wanted to do a compression test on my 5vz engine. Here are the numbers
1. 210psi
2. 210psi
3. 180psi(210wet)
4. 205psi
5. 210psi
6. 170psi(190wet)

What has me worried are cylinders 3 and 6.So I added oil to them and the PSI numbers jumped up. Any thoughts?

Also,Im using a tester that I rented form Autozone so who knows if I can trust it.

 

I just did mine about 2 weeks ago. I also just rented the autozone tester.
Mine were within spec besides two were at 190. I didn’t bother adding oil though, but I definitely think it’s just worn piston rings, I’ve got 220k.
I didn’t sweat it but as your #6 is reading 170dry and 190 wet most likely means your piston rings are worn more on that cylinder then the rest. Personally I wouldnt worry about it just yet unless you have the means to rebuild the engine while having another vehicle to drive. I know the FSM states anywhere between 174-210psi is spec, so I wouldn’t say yours are horrible but #6 most likely be your problem cylinder in the future. How many miles do you have on her?

 

Out of curiosity what compelled you to run a compression test?

 

I got results similar to @Ccrowe323 - if you've retested each cylinder enough times with the same results the tool's working correctly.

 

Its got 220K on her. I might reassemble the engine and run it at normal operating temperature and retest those cylinders.

 

Always wanted to do it since i bought the truck 60k miles ago. What really pushed me to do it was I recently found a crack on the clean side of the airbox, and the engine huffed a bunch of dust for who knows how long. I noticed a little bit of power loss too, Cleaning the MAF helped. Could also be a dirty throttle body.

 

The FSM does state the engine should be up to temp and should be checked as quickly as possible. I would say get it up to temp and check those cylinders first.

 

Eh, I tested the engine cold with numbers you guys were getting. Not gonna hurt though of course.

 

Those tests were with the engine warm, although by the time i got to cyl 6 it must have cooled down some.

 

Ok, I Just came back from another ride. Cyl 3 was at 190psi dry and cyl 6 was at 210 dry. I hope the burnt up oil i put in there earlier didnt skew the results. Ill visually inspect those two cylinders with an endoscope when i get one.

My fear is that I dusted my engine with the dust scoring the cylinder walls.

 

Overthinking it my man.

 

Maybe. But that means I care about my baby.

 

I gotcha - but I almost guarantee you did nothing to the engine by opening up the spark plug holes and putting a couple drops of oil in there. Either way what’s done is done.

 

Compression test on my truck was done today, and since this is the newest thread I could find with someone posting their results, thought I would add mine.

5vzfe 305,928 miles. Never been rebuilt. The only reason I wanted it tested is because I plan on adding the supercharger and wanted to make sure I didn't have a turd of an engine before doing so. Engine runs great.

1 - 180psi
2 - 175psi
3 - 190psi
4 - 180psi
5 - 175psi
6 - 185psi

 

If it runs good and the mpg are around 20 wouldn’t worry about it

 

Looks good.

 

20mpg would be awesome, but my truck hasn't been that frugal for a while now. 33" MT tires, armor, sliders, front and rear steel bumpers, tire carrier with cooking surface, camper, solar panels, batteries, etc... has brought my average mpg down to around 13-14 (Although I can get up to 17 with just highway driving only).

Thanks. I thought they looked like good numbers, especially for the mileage. Glad you and @TWJLee both agree as well.

Next plan is to take it to a tuning shop to get baseline numbers to use as comparison for a before and after supercharger install.