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1996 Toyota Tercel. Smog technician says cylinder compression is low and is causing high HC.

Hello, my car failed smog. The guy at the shop said that the compression was low and it failed the HC measure with an 88 @ 15mph. It passed @ 25mph.The compression test showed these numbers: 1.160LBS 2.140LBS 3.120LBS 4.160LBS The man at the shop told me that if I put on a new catalitic converter the car would have a bout an 85% chance of passing. I would like to ask your opinion before I spend the money. Thank you for your time, Ron
Answer:

In our opinion your 1996 Toyota Tercel's compression is not low. There is a slight variance between cylinders but this is not uncommon for a 1996 model vehicle. However your smog technician is correct, a new Catalytic Converter will more then likely get your Toyota Tercel to pass the smog check; especially if the CAT that is currently on your Toyota Tercel is the original one. The only thing to consider is that the CAT currently on your Toyota should be defective or not functioning efficiently in order for the new Catalytic Converter to get your Toyota to pass the smog check. If there is nothing wrong with the current CAT, chances are a new CAT will not help anything. Your Toyota Tercel's CAT has significant impression on HC, CO and NO results. If defective it will absolutely cause an emissions test failure. posted by SmogTips Support

2ND QUESTION: My cat was old and not functioning correctly. The new one did the trick and my car has just passed smog. Thank you again for your reply and opinions. Should I worry about the compression results at all? 2ND ANSWER: Not really... 10 to 15 lbs variance between cylinders specially on a 4 cylinder is not much to worry about. You can start using some fuel additive to clean carbon deposits out of the cylinders if you wish. That might make a minor improvement over long term use, however considering the cost of the additives you consider whether it's worth while. posted by SmogTips Support

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