I am posting this for anyone that might have issues with hard shifting, engine tapping noises, engine rattling at cold start-up, , engine hesitation on acceleration, or poor fuel mileage. These are all symptoms that I have put up with since I bought my car about 6 months ago. This car had been in storage for 5 years and not running when I go it which turned out to be a bad fuel pump. After I got is running, I have 1 lifter that would tick off and on and all of the above symptoms. I thought it would clear itself up after awhile of running Seafoam and Marvel Mystery Oil. After a week of driving it, I found the lower intake gasket was leaking water so, I replaced it along with the valve cover gaskets which were leaking oil. A month rolls by and I replaced the leaking oil pan gasket. All this while, the lifter tick would come and go but got worse in the past 3 weeks. The car has always had a firm shift even after I replaced the fluid and filter as well as the 1-2 accumulator. It always had a slight hesitation if I accelerated from a stand still. When I would start the car in the mornings, it sounded like it had loose rod bearings or perhaps some piston slap. That noise would go way after a minute or 2. So finally, I decided to remove and inspect the lifters. There is was! One of the lifters had a missing retainer clip and broken metering plate! I found half of the metering plate and the piston itself laying in the intake valley. Now..the piston may have fell out when I removed the lifter. Im not sure. The pushrod had deep wear spots on the shaft where it rubbed against the head which leads me to think that the piston had indeed fell out and the pushrod was just flopping around inside the lifter housing. I installed a new set of 12 GM factory lifters and 1 pushrod. This car has never ran so good! No rattles even at cold startup. No hesitation. Smooth shifting! Smoother power band and more power. Very quiet running engine now and , I just checked the fuel mileage and got 26 MPG which was a mixture of in town and highway driving. Oil pressure is at 60 PSI at highway speed and 45 PSI at hot idle. Im running Valvoline 10w-30 Synthetic and a Wix XP oil filter. My engine has 115,000 miles on it. I hope this helps someone reading this that has some or all of the same symptoms. Sometimes, the smallest mechanical issue can cause numerous issues. Also if you ever have to replace the lower intake gaskets, do yourself a favor and remove the lifter retainer shields and do an inspection. I sure wish I would have the first time around. One more tip. Get yourself a buddy to help you remove the hood when doing this job. those 4 bolts will save you a lot of pain and you'll actually be able to see what you are doing! Thanks for listening!
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My '99 Firebird Story and How I fixed It
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