The Toyota Tacoma contains either a 4-cylinder or a V6 engine. When the engine runs poorly, burns oil or loses potential, a compression assessment is a brisk and apparent habit to bargain away the goal. After performing the corroboration, compare the results to the recommended compression ratio to diagnose problems inside the engine, such as worn cylinder walls, piston rings and valves.
Instructions
1. Prepare for the compression check by warming up the engine in the Toyota Tacoma. If you perform the test while the engine is cold, the results will not be accurate. Turn off the engine and disable the ignition system to avoid electrical shock during the test.
2. Remove all of the spark plugs from the engine. If the Toyota Tacoma contains a 4-cylinder engine, there will be four spark plugs, and if it has a V6 engine, there will be six. The last number that it jumps to is the compression number for that cylinder. Write down the number and move on to the next spark plug hole.4. Perform the compression test on each of the spark plug holes, keeping a record of all the compression numbers and then compare them.
Insert the compression tester into one of the spark plug holes.3. Crank the starter to rotate the engine. This builds compression in the cylinder, causing the needle on the gauge to jump.
The numbers should be similar and fall within 10 PSI of each other.
5. Compare the compression numbers to the recommended compression ratio for a Toyota Tacoma. For model years 2005-2008, trucks containing a 4-cylinder engine have a ratio of 9.6:1 and trucks with a V6 engine have a ratio of 10.0:1. For model years 2002-2004, a 4-cylinder engine has a ratio of 9.5:1 and the V6 has a ratio of 9.6:1. Compression numbers should fall within 15 PSI of the recommended compression ratio.
6. Retest any cylinders that have a low compression number. Add a small amount of motor oil to the cylinder before performing the test to see if the number increases. If it does, the cylinder has worn walls or piston rings. If it stays the same, the cylinder has worn valves or valve seats.
