The_Honda_Guy

Well, before I start doing my tune-up on my Accord I wanted to make sure my main things were in good working order. I decided that I would do a compression test and a cooling system pressure test. This would tell me what shape the valves, rings, pistons, headgasket, and cooling system components were in. The vehicle has 166k on it. So here's my results.

First I did the cooling system pressure test. I hadn't noticed any leaks at all, nor have I lost any coolant in the passed 6 months I've had the car, so that was a good start. I took the cap off and inspected the overflow tank and underneath the cap for any signs of oil indicating a leaking headgasket. The coolant was bright green like it's supposed to be and there was no signs at all of dirt or contamination. While the vehicle was cold I hooked my pressure tester up and pumped it up to 17 PSI. I know the cap is around 14 PSI, but I pumped it to 17 so that leaks would show faster if there were any. I inspected around all the hoses, clamps, head, radiator, and interior and found no leaks whatsoever. Generally the gauge should fall 1-2 PSI over a 15 minute period while it's hooked up to the vehicle and mine only fell about 1 PSI, maybe less. Then I let the pressure back down to 0 and started the car. It slowly built pressure as the vehicle warmed up. Usually when you have a headgasket leak the car will build pressure quickly and you'll notice small bubbles coming from underneath the cap, which I saw no bubbles at all. From the results of the test I could indicate that I had no leaks and no problems with the cooling system. The vehicle does not overheat and the temp gauge stays slightly below the middle mark while idling and driving the vehicle, indicating that the cooling fan is working correctly. No problems seem to be found at all.

Next I did my compression test. I let the vehicle warm up to operating temperature, then removed all the spark plugs and wires along with the ECU fuse. I then started my girlfriend's Civic and hooked up jumper wires between her car and mine so that my battery would be recieving a full charge and allow the engine to turn over at it's full potential. Then I had my girlfriend hold the throttle all the way open and crank the engine for approximately 6 seconds, allowing it to get a full 5 or so cranks in. Here are my results.

Cylinder 1 - 180 PSI
Cylinder 2 - 180 PSI
Cylinder 3 - 185 PSI
Cylinder 4 - 185 PSI

All of the cylinders on the first cranks were about 80-90 PSI, then finished off at what I listed above. The Hayne's manual states a standard as 178 PSI and a minimum of 135 PSI with a 28 PSI maximum variance between cylinders. According to these numbers the car checks out perfectly, indicating that the valves, rings, pistons, and headgasket are in perfect working condition. Also, the vehicle burns about 1.5 quarts between oil changes, which is well within specs. Current specs on oil usage state that a quart every 1,000 miles is considered normal, even on a newer engine.

I still plan on doing a vacuum test and fuel pressure test to complete my tests. After performing those there shouldn't be any other tests I need to perform. Any other tests or suggestions?

hmbtjc29

Is there something wrong with the car or are you bored and just want something to do? Or...you could be wanting to prove to yourself and others that you are capable of running these "tests". Also, which car/engine? If the car runs fine, leave it alone and just do routine maintenance.

The_Honda_Guy

No, nothing wrong with the car, I was just doing all these checks to check for any problems before I start my tune-up. I haven't noticed any problems with the car, but figured I can't be too careful with it having 166k on it. I know I'm capable of running these tests because I am an Auto Technician at a Chrysler/Jeep/Kia dealership, I was just asking if there's anything I may have missed.

hmbtjc29

I was just playin man... I guess unless you want to check oil pressure and fuel pressure you should be good. Don't forget to check/adjust valve lash.

The_Honda_Guy

Yea, like I said, I want to do a vacuum, fuel pressure, and oil pressure test. Is there any other way to do an oil pressure test besides removing the pressure sensor? Also, is there any reason to do a wet compression test if the dry results are good?

The_Honda_Guy

Well, I realized that there's no reason to do a wet compression test if your dry results are good and the vehicle isn't burning any more oil that it usually should. Also, how the [freak] would you do an oil pressure test if you have to remove the pressure sensor? Where would you get a connector to screw in in place of the sensor or is there another way to do it?

Blamm!!

Have you considered doing a PH sample of soil? It can greatly affect the appearance of lawns and other vegetation.

The_Honda_Guy

We do have the oil pressure setup at work that screws into the pressure sensor outlet on the block. Apparently it's just a mechanical gauge setup. I also found all the fittings for the fuel pressure gauge setup too. I plan on doing these two tests on Monday along with the vacuum gauge test and see what I get.

The_Honda_Guy

Well, I tried today to hook up a fuel pressure gauge to the service port located on the fuel rail but ran into a few problems. I first took off the small screw but then realized quickly that there wasn't going to be a fitting small enough to screw into the hole. I then took out the larger bolt to see if I could get a fitting into there. I had a few that worked but the problem was that the fuel found itself able to work passed the threads on the fitting since the original bolt had a crush washer to help seal it. Anyone have a suggestion? I'm guessing I may need to stop at the Honda dealership and see if they've got a fitting that would work or try and hook the gauge up elsewhere on the fuel system.

Also, I checked out the oil pressure gauge thingy too. Problem is that the gauge we have isn't a mechanical gauge. The vehicle needs to be OBD2 compatable, which mine isn't so I was unable to use the gauge. I guess I'll have to stop at the auto parts store and see if they've got a mechanical gauge and fitting that I could use instead.