Piston Slap: I'm on Tonight, You Know My Gauge Don't Lie!

Sajeev Mehta
by Sajeev Mehta
piston slap i m on tonight you know my gauge don t lie

Dave writes:

Hello Sajeev,

I just bought a 2000 Saturn LW1 6 weeks ago. It has a L4 2.2 Liter engine with 200,000 miles on it. After 3 weeks out of the country I came back and started it up. Was a little rough then smoothed out. I just changed parking spots. Did this one more time. The third time starting it up it would not fire. No strange noises, just no running engine. I suspected bad ignition coil. I had just changed the spark plugs before my trip and they had about 50 miles on them. Ignition coil was fine at all four points using a ignition tester. I even put new plugs in again. Fuel rail has the specified 60 PSI. Theorizing that may the fuel injectors were shut down i tried starter spray in the air intake. The motor will not fire. A compression test with a gauge picked up at advance gave me less than 10 PSI on the two outer cylinders and about 24 on the two inner. The Haynes manual is very unhelpful and only states for compression specs. that the lowest compression cylinder value should be no less that 70% of the highest compression cylinder value.

I read on-line (http://www.saturnfans.com/forum/showthread.php?p=1781795) the same but that no cylinder should be less than 100 PSI. While cranking the engine there was some light smoke visible behind the engine above the exhaust manifold, but unable to determine the source.

My question is: are you aware of catastrophic head gasket failures on these engines? I am surprised that the engine will not fire at all even if the head gasket does have a problem. I have removed the valve cover and see that the timing chain is still there and working.

When I changed the plugs last month I applied anti-seize thread sealant to the plugs as instructed in the manual. I am now having wild imaginings that the anti-seize thread sealant got into the cylinders and impregnated the gasket and is somehow responsible for this catastrophic failure. I am going to tear into the engine tomorrow and try to replace the head gasket, because i need to get this car running again ASAP. I am being hopeful and unrealistically optimistic that I cold get some input/ thoughts from you before morning when I start this laborious task…


Sajeev Answers:

You are in a tough spot: a seemingly severe mechanical failure. This is when we tend to trust everything we see or read, even if we shouldn’t. It’s not your fault, but you need to verify what you are seeing. It’s like getting a second opinion when a doctor tells you that you have 6 months to live. Because the lack of compression has sent you down a path of diagnostic madness. Which truly sucks.

So try another compression gauge. I don’t know why, but these things are terribly unreliable and not durable. Bang it around in a toolbox in your garage (or the rental counter at your local parts store) and the needle won’t move nearly as much as before. The odds of you losing that much compression on all cylinders that quickly just doesn’t add up: so I think the tester is bad.

I think you need to check for spark the old-fashioned way…put a screwdriver in the end of a spark plug wire and lay it near a piece of metal…you should see a spark when you crank, and it should be pretty strong. Google this for more information.

Good luck. I suspect the ignition module finally crapped out. Did yours ever get the recall?

Send your queries to sajeev@thetruthaboutcars.com . Spare no details and ask for a speedy resolution if you’re in a hurry.

Join the conversation
2 of 43 comments
  • Forraymond Forraymond on Dec 06, 2011

    I bought a 2001 LS200 brand new and put 150K miles on it in 3 years. I never had one problem. Traded it for my Vue in 2004. Two of the cheapest to drive cars I have ever owned. Both have the 2.2L 4. My '97 SL3 was even cheaper to run because of the high MPG. Hit and run ended that SL3.

  • Bikephil Bikephil on Dec 06, 2011

    bad battery.

  • Pig_Iron ASTC 3.0 AM radio was successfully demonstrated at CES. It is a common standard shared with terrestrial television, so the audio equipment is commonized for broadcasters. And no royalty fees to pay, unlike HDRadio which has been a less than stellar success. 📻
  • Art Vandelay Crimes that are punished with fines encourage abuse by those enforcing them. If it is truly dangerous to the public, maybe jail or give the offenders community service. People’s time tends to be very valuable to them and a weeks lost work would certainly make a high earner think twice. If it isn’t a big danger why are police enforcing it (outside of raising money of course). Combine it with a points system. When your points are gone you do a week imitating Cool Hand Luke.
  • Cha65697928 High earners should pay less for tickets because they provide the tax revenue that funds the police. 2-3 free speeding tix per year should be fair.
  • Art Vandelay So the likely way to determine one’s income would be via the tax return. You guys are going to be real disappointed when some of the richest folks pay no speeding fine the same way they minimize their taxes
  • Teddyc73 A resounding NO. This has "Democrat" "Socialism" "liberalism" "Progressivism" and "Communism" written all over it.