How do you do a compression check for a V12 without taking out each spark plug. Can you measure it through the diagnostic system that Ferrari uses. I have been told to get an extended warranty at some stage (I have a new F12) the factory insists on doing a compression check. Any thoughts please? Thanks
NO to the SD series of testers, or the new wireless connection... compression tests indicate absolutes in terms of engine health: either you have an absolute problem(bent/burnt valves, burnt seats, broken piston/rings/liners etc IF this test shows a problem, THEN you do a leak down to ascertain the relative problem. For example: with a 4 valve engine: you can have a pitted valve seat with 20% leak down-you will NEVER feel this or otherwise suspect. A tail pipe co sniff will show 800-1400ppm HC unburned....this is an RELATIVE failure in terms of absolute limits... Therefore: they don't want to extend a warranty on a car with either a huge problem, or, one just around the corner.. .8-12% leak down WILL degrade, its merely an undetermined rate at which it will become "a check engine light" for long and short term fuel strategy based on O2 regulation outside of range parameters. IMO: the extended warranty is a great value should a problem arise. If no problem EVER arises, then it seems like a wasted fee-what is your risk profile?
Thanks for your great reply! I have no issues but hate the thought of unnecessarily taking out each spark plug for this test when another method can be used. I recall in another car I had they did a test and can't remember whether it measured the voltage current for each cylinder (which was accurate apparently) without removing the spark plugs. Any one had this done to an F12 or any 12s? Thanks!
Depending on which warranty you want, and the mileage of the car, Ferrari requires a compression test that uses a Picoscope to calculate the health/compression of the engine. The Picoscope uses a pressure transducer screwed into only one spark plug hole and a current clamp on the positive battery cable. It compares the cranking amperage of each cylinder and uses this to determine the compression/ general overall health of the engine: https://www.picoauto.com/library/automotive-guided-tests/relative-compression-petrol/ https://www.picoauto.com/library/automotive-guided-tests/WPS500X-In-Cylinder-Compression-petrol-cranking/ https://www.picoauto.com/library/training/compression-testing As T. Monma has pointed out, this test is not very accurate when compared to an actual compression test/cylinder leakage test where every cylinder is tested. It is only required by Ferrari to quickly determine the general overall health of the engine before they authorize an extended warranty. Generally modern Ferrari engines such as an F12 are pretty bulletproof. I have yet to see any engine issues other than oil leaks on any V12's since the 456 valve guides/camshaft wear problems. I would be more concerned about DCT transmission problems on the newer cars.
Ford has had a scan tool compression test option for a while now. A friend of mine tested it out against a normal compression gauge. It was actually quite accurate. That's said..we are dealing with ferrari here..
That whole post on the pico compression test is very interesting to me. I have been searching for a 612 OTO for a couple of months and have looked at the service records for a number of 612s . All that have been under the extended powertrain warranty have shown compression tests each and every time the warranty was extended. Some 4 sequential years. What struck me as odd was that if there was problem, seems like warranty would have to cover it since the vehicle was covered by a powertrain warranty. In any case the dealer charges from $900 to $700 to do the test to charge the $7000 for the one year warranty. Looks like a profit center to me if it is done quickly with the picoscope as I now understand. Also no compression problems were ever noted on any of the ones I examined. As everyone says, it’s not the engine per se that goes bad. Sent from my iPad using FerrariChat.com mobile app
It is pretty unlikely that you will have $7000+$700-900 worth of problems with a 612 in one year. I have never seen an engine issue with one of these cars. But if you are unlucky, you could have a DCT transmission problem that could cost upwards of $30k, or an electrical issue, (Bad dash, etc. which can also get expensive very quickly). If treated well and driven regularly, the 612 should only require regular maintenance. You can roll the dice, not get the warrranty and probably come out ahead in the long run. If you are not the gambling type, then get the warranty.
I agree completely, no real engine issues per se on any of the 612s I researched. Some F-1 Leaks/ F-1 ECUs , which I would hope would be under power train,But no compression problems, bad valves, bearings, etc. , All had numerous ball joints, tie rod ends,before 15,000 miles and some various ECUs and A/C issues.And of course, Lots of Dealers running up the service bills.
