Q: 2001 Pontiac grand Prix 3.1l engine tapping

asked by on

2001 Pontiac grand Prix engine starting tapping. About a month later I noticed coolant disappearing. A couple of weeks later I found coolant in the oil. Pulled the engine and tore it apart and found the intake manifold gasket failed on 4 ports. All the hydraulic lifters had collapsed, the crank and camshaft had damage (grooving) due to the leak. Completely pulled everything apart, had the block vatted and new camshaft bearings installed at NAPA. Rebuilt the engine replacing everything except the pistons, connecting rods, valves (did replace seals), valve springs and fuel injectors. Also replaced temp sensor, crankshaft position sensors, fuel pressure regulator, vacuum lines, coolant hoses, spark plugs and wires. Put everything back together filled with oil and coolant. Starts and runs but it still has the same tapping as before the leak. I checked the valves and springs when replacing the valve stem seals and they were good. Tapping is loud enough to hear inside the car. Help?

My car has 120000 miles.
My car has an automatic transmission.

Hi there. Typically an engine tapping noise is caused by either cylinder head lifters that are loose or worn out, rockers and valves not properly adjusted, a timing belt or timing chain that is loose or crankshaft / cam out of alignment or not balanced correctly. Oil restriction problems are also a leading reason for this type of problem. The problem with an overheating issue is that is can cause a lot of internal damage, especially when coolant mixes with the engine oil. An engine knock can also be produced by an ignition timing problem or misfire, which is also common after an overheating issue, especially if you didn’t replace the electrical wiring to sensors or fuel injectors as well.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. 2001 Pontiac grand Prix 3.1l engine tapping

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car won’t start. New fuel pump, fuel pump relay and battery. What could be the issue causing my car not to start?

Hi Giselle. Thanks for contacting us tonight. To be honest, this is rather confusing. In most cases, when a vehicle progressively slows down, stalls and will not start again, it's a fuel delivery problem. However, if your engine will not...

Q: Should spark plugs be replaced early if 1999 buick century is over 18 years old?

It certainly would not hurt to remove the spark plugs to take a look at them to determine if they need to be replaced. A normal looking spark plug will have a grayish tan color to the threads and electrode....

Q: When my car is idling the rpms and battery gauge drop off and it acts like it wants to die.

Hello Nick, What are you are describing sounds like potentially a dirty or failing idle air control valve which reads the air intake into the engine. The computer uses this data to make adjustments to the air/fuel ratio to keep...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...