There are methods for testing the injectors and fuel pumps but much of this involves the problem that faces mechanics and shops. Money. At least the shop may reuse the expensive equipment.
This is not practical for a DIYer for quite likely a one time use.
My suggestion is to not worry at all about the fuel system at this point. If the compression is down that much then the fuel system is irrelevant. The engine is problematic and on borrowed time. I might add that when you do the wet compression test only add oil to one cylinder at a time. Otherwise the piston upstroke on the other three is going to douse anything in front of the plug hole with oil.
I mentioned tech people not knowing what they are talking about. At one time Subaru had a hesitation problem with new cars. Several owners were irritated as they should be. It was very subtle but noticeable.
I could find zero wrong with the cars but noted the problem.
While looking at the near new fuel filter I noted that the direction arrow was pointing back to the fuel tank. A filter can flow more in one direction than it can the other. I switched the filter around, modded the hoses a bit, and problem solved. Back to the wrong direction and problem returned. So I revamped it again in the correct direction and sent it out with no more issues. I then walked out into the lot and checked the filters on 4 or 5 new Subarus. All the same; backwards.
I called Subaru corporate and told them of the issue. The next day they called back and agreed the filters were all backwards from the factory (and with pre-molded hoses which made a change irritating) but āour technical experts say it should not make any differenceā.
See what I mean? Tell that to the POed customers and explain why you are assembling things backasswards while reversing the filter cures it all.
Nope. Usually, at most dealers Iāve been to, techs donāt even see the car. The used car manager or one of his assistants is usually the only one to look the car over.
If thereās a fuel pump under the valve cover, definitely should be considered a suspect. If itās a high pressure fuel pump, prime suspect. Under the valve cover seems an odd place to place a fuel pump, but maybe itās there for a safety reason. Any fuel leak under the valve cover will drain right into the crank case, b/c the oil thatās pumped upstairs to lube the cam needs a path to drain back down into the oil pan.
I just did a dry/wet compression test with the engine warm. At first I was just putting a little oil in and wasnāt seeing any difference between dry and wet. I thought I might not be putting enough in so I started putting more in and got these results. So maybe if I put even more in the numbers would be even higherā¦ I didnāt want to put too much in and break it though. How bad is this?
Looks like your compression gauge is inaccurate, very unlikely all four cylinders are failing. If one cylinder were to be low, the computer would pick this up long before you could notice a problem.
Focus on the fuel leak; the fuel pump. How long after an oil change do you see an increase in oil level?
I wouldnāt be surprised if theyāre all low, these engines are notorious for burning oil. Isnāt it normal for any engine to have slightly better compression when you put oil in the cylinder? 20 psi in cylinder 1 seems like quite an increase though?
I can smell gas in the oil pretty pretty quick, probably within 3-4 days of changing it.
Looks like a ring problem to me. Ring problems are caused byā¦
High miles wear.
Irregular oil changes.
Running the engine low on oil.
Overheating.
Air leaks.
Washing the cylinder walls down with gasoline.
EGR faults.
Days of adjustable distributors; way incorrect timing and not applicable here.
Changing the oil could possibly resolve the washed cylinder wall issue IF caught quickly and I doubt that is the case here.
Whenever Iāve seen potential issues I run compression tests twice; and usually with a second gauge just to verify but the second always backed up the first within a few pounds. Only time Iāve seen a gauge error was with my Snap-On and that was due to debris entering the hose, getting caught in the Schrader valve, and failing to hold pressure. Easily resolved. JMHO.
Just an addendum. If you have access to a vacuum gauge check things that way. Cheap and easy and preferably before a compression test.
An engine with good compression is going to show roughly 20 t0 21 inches at idle with a rock steady needle.
If itās at 15 to 17ish, etc thereās a compression issue.
Suggest OP should pay shop for independent compression test results before presuming ring or valve problems. In my experience compression gauges sold to diyāer tend to be miscalibrated, read on the low side, even lower the older they are. OP, your compression gauge is the type the screws into the spark plug threads, right? The o-ring seal where it threads in is in good shape, right? You cold try coating that seal w/a little oil, see if that changes the readings.
If the shopās gauge produces normal (higher) results, you have revived your gauge at the same time, b/c now you know how to recalibrate the readings.
Yeah I think Iāll do that. Itās a brand new screw in type so itās in good shape, the gauge wasnāt bleeding down so I donāt think there were bad seals.
Do you guys think this fuel pump sounds excessively loud? The high pitch jackhammer type sound is coming from it. Iām wondering if it is bad and leaking into the engine through the bottom of it.
Warning: Loud so turn down your volume before playing, I wouldnāt let me upload it as a non short videoā¦
Sounds bad to me, but I donāt know what a Kia should sound like.
My take, focus on the fuel system, not the rings.
My story: new lawn mower, I had less than five hours on the engine. Went to start its a week after last use, would not crank. Put a wrench on the flywheel, couldnāt budge it. Checked the oil, way up the dipstick,smelled like gas. Noted the gas tank was nearly empty. Drained it, got a gallon of oil/gas out of a two quart crankcase. Pulled the spark plugs, cranked it, raw gas shot out of the cylinders.
B and s had a problem with their carbs shut off sticking evidently. So drained the tank and locked the engine. Taryl covered it in one of his YouTubeās. Fun times.
Interesting. When my lawnmower carb-inlet valve sticks open, an uncommon occurrence, the gas in the tank doesnāt leak into the cylinders, it leaks out onto the ground through the hole in the rubber priming-bulb thing. Any leak out that hole is how I know it is time to give the carb a cleanout.
Mine is a Sears lawnmower, believe engine is made by Tecumseh, 4 cycle, has proved quite reliable, purchase mid-80ās.
Hereās a lawnmower tip I recently discovered: If that priming bulb stops working, wonāt push a little gas into the intake when you press it, no worries; if you spray a short burst of starter liquid through that hole in the bulb, thatās usually enough to prime the engine.
Well tech has been out of business for at least ten years and all the machine tools sold to the Chinese. I stocked up on parts when I heard since my son still has a blower with tecumseh engine. Not the same problem as with the later Briggs carbs. Tarly has got a YouTube on it somewhere.
