Hi, I ran an engine cleaner through my engine last night, changed the oil and filter and I still have this loud ticking and pulsing exhaust. I'm trying to figure out what I should do next to isolate the problem. I now think that it is either a burned valve on one of the heads or one of the lifters. Note that I have a spare head in my garage that was just professionally rebuilt. So, if I isolate a bad valve or seat, I can swap out the bad head with a good one with good valves and seats. I need to figure out where the problem is. I only have one rebuilt head and want to avoid the cost of buying another one. However, if it is the lifters, I don't mind changing more than one. At $15/piece I can afford a few. Also, I have a spare engine gasket set which I was saving for another engine rebuild, but I am willing to use it. Here's where I am now. Problem: pulsing exhaust. HC levels measured as pulsing up abnormally high. Tests done with professional emissions equipment. I passed SMOG by putting a new cat on. the cat is masking the problem, not fixing it. I want to get to the root of the problem. Engine vibrates. Appears to be one of the four cylinders. Not sure which one. Loud ticking sound appears to come from the center of the engine, near the cam shaft. I have not been able to figure out if it is on the left of the right. Diagnostics and tests completed - changed all four fuel injectors and rails - changed all plug wires and plugs - ran Marvel Mystery oil through the system for hundreds of miles - flushed the engine - adjusted valves and timing three times - last done by professional - replaced rotor and distributor cap - checked compression, balanced and good - last done by professional - new fuel filter, O2 sensor, auxiliary air regulator - have oil pressure gauge on engine and pressure is within specs Have not done leak-down test (don't know how). I have these tools in my garage: - compression tester, digital multimeter with tach, full mechanics tool kit Please advise on what I should look for. I don't mind taking the heads off, but I am hesitant to do so since the gasket set is so darn expensive. Also, when I get the heads off, do the lifters fall right out? The last time I took the heads off, the engine was still in the vehicle, so I didn't deal with the lifters. How can I tell if the lifter is bad? Thanks. Regards, Craig |
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