Compression cylinder low #2 and #3 cylinders.

SOURCE: what is the cylinder compression psi fpr the 2.0 liter engine

usual on 4 cylinder around 175psi.225psi is very high for your car,150psi seems ok,you may have two problems.A leaking head gasket and high compression due to carbon build up on the pistons.Check your Hyundai Dealer to see is this problem is covered under their 100,000 mile warranty,it should be.IF not then
the head needs to come off and had gasket replaced along with clean the top of pistons since they are right there,sounds like and easy fix.also check condition of radiator,and I would rec. replacing thermostat since some Hyundai models had problems with their thermostats

PAUL MC G

• 1280 Answers
• Posted on Oct 04, 2009

SOURCE: one cylinder has zero compression. took head off

OK!... did you do a cylinder 'leak down test'?.. .if not, do it! If any 'unacceptable' leakage, have the head REDONE! NOW!.. you must BE SURE the valve timing is accurate!... Go to www.hmaservice.com and register( Vehicle by VIN). Afterward, you have access to shop manuals, service bulletins, wiring diagrams, etc. about your vehicle.

SOURCE: NO COMPRESSION ON ALL CYLINDERS - TESTER GAUGE GOES UP THEN DOWN

The fault may very well be with the tester itself: The compression tester should have a check or "HOLD" valve which causes the needle on the gauge to REMAIN at it's highest recorded point. For example, my 1993 Isuzu Rodeo had a compression of 160 psi. The gauge "holds" the needle at the measurement UNTIL THE VALVE IS RELEASED-(mine had a button that needed to be pressed to release the pressure) then there will be a slight discharge of the pressure contained within, the needle should drop back to zero, and THEN you should be able to remove the tester. What I am getting at is if the pressure drops that fast, I think the "HOLD" valve on it may be defective, OR the tester is not properly sealing on the combustion chamber (stripped threads?). Might be worth buying another one for 20$ just to be sure.

A four cylinder engine, you say? Very rarely will you have ALL of your cylinders exhibit the same pressure loss symptoms. How did the other three cylinders test?

Here are the components required for a running engine to fire:
1-good spark (adequate voltage, good plugs/wires)
2-dedicated fuel supply (fuel pump with adequate pressure)
3-timing (slack in timing chain/belt?)

If the timing belt broke or maybe even jumped a tooth or two, it COULD cause DAMAGE to your engine-pistons hitting valves-if it IS what they call an "INTERFERENCE" engine.

Hope this helps.

Testimonial: "Very helpful insight."

SOURCE: Head gasket blown Hyundai elantra '95

New at autozone/napa relatively cheap mark any wires or hoses u remove also get Haynes book it will give step by step to insure a good result in taking apart and back together u got it that far apart also do new timing chain if u are at 100,000 miles or better it will save u headache later thoose are known for breaking and wiping out the valves and everything else when that high in miles good maintenance is always helpful that far tore apart why not be preventive and safe