2001 Pontiac grand Prix 3.1l engine tapping pontiac grand...

Q: 2001 Pontiac grand Prix 3.1l engine tapping

asked by on May 24, 2017

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

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

I have replace the fuel injectors and now i have a p0200 code aswell a p0300 code. What can it possibly be

Hi there: The P0200 OBD-II code indicates that the engine control module (ECM) has detected a malfunction in the fuel injector circuit. The fuel injector circuit controls the fuel injectors and commands how much fuel and when to spray the...

Car won't let me accelerate.

Hello there, A continued oxygen sensor and voltage code is a sign there is still a problem with your 2002 Pontiac Firebird. You did not say if you replaced the oxygen sensor in question or not. I am going to...

Rough idle, p0300 code, running rich

Hi there. Let me refer you to this article explaining what causes the P-0300 OBD-II error code and possible solutions to resolve the issue. I believe reviewing this article will be very beneficial to you. Thanks.

Related articles

The Best Used Cars to Buy for Occasional Drivers
Not Not everyone relies on their car on a daily basis. Maybe you aren’t the type that deals with a daily commute, and running from here to there constantly. If that’s the case, you may be looking for a car...
Understanding the Pontiac Oil-Life Monitor and Service Indicator Lights
Car symbols, or dashboard lights, are a car service reminder. The Pontiac Oil Life Monitor (OLM) indicates when and what service your car needs.
Pontiac Certified Pre-Owned (CPO) Car Program
If If you’re in the market for a used Pontiac vehicle, you may want to check out cars under their certified pre-owned program. Many manufacturers have a certified pre-owned (CPO) program, and each one is set up differently. Read on...