View Full Version : Bad engine noise - Oldsmobile 3. Hello, this question pertains to my wife's Oldsmobile Intrigue with the 3. Saturday, when returning home from a party, the engine began to make a tapping noise.
I don't know if it started suddenly or if it just slowly became loud enough to hear. It's now tapping constantly while running at any RPM. It seems to do it on accel and decel. It seems to be a little more audible when hot. The engine seems to be running a little rough also. However, the oil pressure warning light has not come on. The noise does occur more frequently with RPM, but it doesn't seem to necessarily happen every revolution.
I tried listening for it with a mechanic's stethoscope, and the noise is loudest when listening to the block or lower intake manifold. The noise is definitely more substantial than a "tick" or "ping", but not really a hollow "knock" or rap. The best way I can describe it is it sounds like a gnome mining for gems with a rock hammer.
So what do you guys think?How to Change Your Oil (COMPLETE Guide)
Do you have any idea what this might be? Give it to me straight. Ive had this happen on many 3. But looks like your going to be changing lifters Good luck!
GM 3.4L Engine Specs
Thanks for the reply. I had thought of lifters for a moment, but remember that this is a DOHC engine. The noise was much fainter coming from the cam covers. So I don't think it's a valvetrain issue, unless possibly the timing chain is slapping around. There was a GM technical service bulletin for lifter noise on the 3. Do a search for it on google or Yahoo and it will come up.Automotive Forums. I have a Intrigue with 91, miles on it. For quite some time I was fairly sure I heard a knock, especially on cold mornings before the engine warmed up.
I had it in a local garage twice so they could have a listen. Both times it came back with "we can't hear anything abnormal". So finally I took it to the dealer and they did an oil sample.
It turns out that the oil has a very high metal content, an indication that something is coming apart inside, and they hear the knock. Of course my confidence level with the local mechanics and their diagnosis skills is shot. The dealer tells me that this 3. That info really shocked me. So I called a professional engine rebuilding shop in another town, and they called me back about an hour later and said they too could not find any parts for the 3.
Does this sound familiar to anyone? If you have info about parts availability or rebuilt engines, please let me know. From what I've read, unfortunately I think it's true about the "unrepairable" nature of this engine. It is a very complex design too which doesn't lend itself to repairs at the dealer the FSM consists of two LARGE volumes, one of which is pretty much dedicated to the engine. Of course some of the accessories can be changed out but much of the engine internals are "non-user serviceable" and it's just more feasible to replace the engine if catastrophic failure has occurred or is iminent.
When you say the oil has "high metal content". A new engine may be your only option. I thought it was a marvel of engineering. Unfortunately, this engine was not cost effective for GM and so it was scrapped in favor of the newer "premium" engine designs.
GM decided to eschew these premiums in order to make the engine more cost effective in the vehicles it was going to be used in. A wonderful engine not given the chance it deserved!General Motors' 3. This engine has been the forerunner to the manufacture of the Cadillac Northstar 4. With a block made of metal cast iron, this 6 cylinder engine has 3 cylinders on each side arranged in a V shape.
The right bank cylinders 1, 3, 5 are on the cowl end of the engine section whilst the left bank cylinders 2, 4, 6, are located on the front side of the car. The crankshaft, which is retained by bearing caps that are machined with the block for proper alignment and clearances, is held in place by four bearings. The aluminum cylinder heads have two intake and two exhaust valves for each cylinder.
These heads contain pressed-in valve guides and valve seat inserts. The aluminum camshaft carriers each contain one intake and one exhaust camshaft. The aluminium in the carrier serves as the camshaft bearing surface. The camshaft thrust plates, which control the camshaft location, are mounted on the rear of the carriers. The camshaft drive is a bi-stage system. Initially, it transfers power from the crankshaft to an intermediate shaft via a chain drive. The second stage uses a belt between the intermediate shaft and the individual camshafts.
Both chain and belt tension is set and maintained by fully automatic tensioners. Timing must be reset if sprockets are removed from their shafts.
Pins or keys are not used to establish camshaft to crankshaft timing in this engine. The GM3. The piston pin is offset 0.
This permits a gradual change in the thrust pressure on the cylinder wall as the piston moves in its path. Pins are chromium steel and have a floating fit in the pistons. They are kept in the connecting rods by a press fit.
Connecting rods are made of forged steel.
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Full pressure oiling is channelled to the connecting rods by drilled oil routes from the adjacent main bearing journal. This 3. The torque of the engine is Nm at 4, rpm. This engine drives the front wheels only. This article was written by the It Still Works team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information.
To submit your questions or ideas, or to simply learn more about It Still Works, contact us. Pistons The GM3. Performance This 3. References W Body: GM 3.Diagram Base Website Full Edition. This is a matter that several of my readers asked me. This is a topic of great interest for me personally, since it means a whole lot of graphic design comprehension.
From the picture world, it is possible to consider there are two types of words - those that have particular meaning and those that don't.
All the word shapes have a set of meanings. For example, a triangle signifies three, which is due to its shape. To draw a note, all you need to do is to select the appropriate shape from the list. However, for a fantastic diagram to be carried out properly, it ought to have no repetitions. Thus, your diagram ought to be connected rather than a circuit. Following that, it's very important to come up with the heading that goes with the first part of the Venn Diagram.
The heading should be something that stands out also has a distinctive look. It also needs to be something that provides an idea about the various parts.
A good heading would be: The next thing that you will need to do is to join the dots. It must then be noted that each dot in different areas of the diagram should have a different color.
The colours used for connecting the dots will differ based on the type of diagram you want to draw. The color to the connecting dots should rely on the kind of word which you want to draw.
By way of example, if you want to draw a capital letterI, then you ought to use white or black dots. The colour of the connecting dots may also rely on the final text that you want to use. Drawing a simple diagram will demand some shortcuts. The principal shortcut is called theclip path. It is a great shortcut since it automatically places the moving points beneath the cursor.
You may easily change the route with your mouse. At length, after you've drawn a Venn Diagram in Word, you should put your text on the diagram. It is possible to choose between small boxes or bold words to be set on the diagram. User Blog. User Blog Global. Securely Verified.The powertrain used in this vehicle consists of a twin cam V6 engine mated to a 4TE electronically controlled transaxle.
The powertrain has electronic controls to reduce exhaust emissions while maintaining excellent driveability and fuel economy. The powertrain control module PCM is the heart of this control system. The powertrain control module is designed to maintain exhaust emission levels to Federal or California standards while providing excellent driveability and fuel efficiency. Review the components and the wiring diagrams in order to determine which systems are controlled by the PCM.
The PCM monitors numerous engine and vehicle functions. The following are some of the functions that the PCM controls:. Powertrain Control Module Function: The PCM constantly looks at the information from various sensors and other inputs, and controls systems that affect the vehicle performance and emissions.
The PCM also performs diagnostic tests on various parts of the system. The problem area is identified by the particular DTC that is set. The module supplies a buffered voltage to various sensors and switches. The input and output devices in the control module include analog to digital converters, signal buffers, counters, and output drivers. The output drivers are electronic switches which complete a ground circuit when turned on. Most PCM controlled components are operated via output drivers.
The PCM monitors these driver circuits for proper operation, and in most cases can set a DTC corresponding to the controlled device if a problem is detected. No Login Required. Q and A Main.
How Things Work.Typical engine data sensor and control component locations on the GM 3. Click on numbers below image for a description. Fuel pressure regulator 2. Mass Airflow sensor MAF 4. Throttle Body 5. Fuel Injector 7. PCV Valve 8. Coolant Temp sensor ECT 9.
Evap Purge Solenoid EGR Valve Question: I have a Pontiac Grand Prix that stopped running, I have put a new fuel pump, and new computer box on it, but it still wont start. Do you have spark, fuel pressure, injector pulse, theft or security light on dash, etc.
You need to start by diagnosing the basics. Car stared missing, was told it was EVAP purge solenoid. Replaced it and drove fine for short time and problem started again and again was told it was EVAP purge solenoid. Why is this happening over and over again. What can I do? The purge solenoid would not be causing an engine misfire. It would cause a check engine light yes, but not affect the way the engine runs.
I have a Buick Century and in the last month or so the engine started making a noise that sounds as if it were literally was a diesel engine. When opening the hood one might there was very little or no oil coming up to top end. This would also cause a misfire on that cylinder.
Removing valve covers for inspection seems the next step after checking oil pressure. How do I remove the TPS shaft from the throttle body? It appears stuck from the right side as viewed from the drivers side. The little piece will not come apart on that side to release the shaft. If you are trying to remove the throttle plate shaft from the body, it cannot be done. If you have a problem, the throttle body needs to be replaced as an assembly. The temperature sensor?
Cannot be the temperature sensor or thermostat.
If the coolant is low, you have a leak and need to get it inspected closely. If it is not low, then you may have a level sensor problem.The GM 3. Top on the list are leaky intake manifold gaskets that can literally destroy the engine if not fixed promptly. The 3. The engine is an enlarged version of the 2. GM made a dual overhead cam version of the 3. The issues: Leaking intake manifold gaskets.
Both the 3. Over time, the plastic would soften and the seals would leak. That would allow coolant to seep into the crankcase, or allow oil to seep out of the intake. At the time GM had recently switched over to DexCool coolant and it was blamed for the leaking gaskets. DexCool gets a bad rap on this one. GM offered settlements to owners. GM has gone through several variations of gasket designs to solve the problem. If you own the 3. Always install NEW intake manifold bolts with a new gasket.
Reusing the old bolts will guarantee a future failure. And, as you disassemble the intake, remember that the exhaust and intake push rods are a different size. Do NOT mix them up.
They must go back in the exact same hole as before or you will get tappet noise. MAF sensor problems. The early generation MAF sensors used with these engines are prone to dirt, carbon, and fuel vapor varnish buildup.
The crud builds on the sensing wires, insulating them from the airflow and causing the computer to miscalculate load and cut back on fuel.
The oxygen sensor sees the lean condition and forces the computer to add fuel. This would show up on a scan tool as short and long term fuel trim add. That additional fuel can cause early catalytic converter failure. The symptoms of a dirty MAF sensor are; rich or lean trouble codes, poor gas mileage, rough idle, black smoke from exhaust or P, P, and P