Slow oil leak from exhaust manifold bolt

This type of noise is usually caused by malfunctioning valve lifters or an exhaust manifold leak. If the noise lasts for more than a minute and completely disappears or dimishes after the engine is warm, the most likely cause is an exhaust manifold leak. If the noise only lasts for a few seconds, the most likely cause is a valve lifter malfunction. You should start your diagnosis with a visual inspection of the exhaust system. Inspect the exhaust manifolds for leaking gaskets or cracks. Black soot marks where the manifold mates to the cylinder head are key indicators of an exhaust manifold gasket leak. Inspect for broken exhaust manifold bolts. Inspect the gasket area where the manifold bolts to the exhaust pipe. Small exhaust leaks can often self seal once the metal engine parts are heated and expanded.
If there are no signs of an exhaust leak and the noise dissipates a few seconds after starting the vehicle, you should suspect an oil control or valve lifter malfunction. Hydraulic valve lifters use the engines oil pressure to expand the lifter which provides a zero valve lash clearance. This prevents the valves from tapping. When the engine is shut off, a valve and spring in the lifter keep it expanded and retain the oil within the lifter. If the valve or spring allows the oil to drain from the lifter, it will collapse. Upon start up, the lifter will take a few moments to "pump up" and expand as the oil pressure builds in the engine. During this time, the valves may tap since there is clearance between the rocker arm and lifter..

FOR MORE DETAILED HELP CLICK THE LINK BELOW:

https://carrepairworld.blogspot.com/2021/06/car-valve-chatter-only-at-startup.html

THIS WILL HELP THANKS.

Td4 leaking oil at the manifold to head I'd say u got a worn manifold gasket , as with all turbo diesels there will always be oil in the boost system and nothing to worry about unless it is dripping with oil and if there is oil on the outside u got a leak not just of oil but of boost to

Hi Juan, I'm AL the owner of Big As Auto Repair

Below is the torque specs for the rocker arm as you requested.

SPECIFICATIONS - TORQUE

DESCRIPTION N·m Ft. Lbs. In. Lbs. Camshaft Sprocket-Bolt 54 40 - Camshaft Thrust Plate-Bolts 12 - 105 Forged Connecting Rod Cap-Nuts 54 +¼ turn 40 +¼ turn - Cracked Connecting Rod Cap-Bolts (Refer to 9 - ENGINE/ENGINE BLOCK/PISTON & CONNECTING ROD - INSTALLATION) Crankshaft Main Bearing Cap-Bolts 41 +¼ turn 30 +¼ turn - Crankshaft Main Bearing Cap Cross Bolts (3.8L) 61 45 - Crankshaft Oil Seal Retainer Rear-Bolts 12 - 105 Crankshaft Damper-Bolt 54 40 - Cylinder Block Drain Plugs 20 15 - Cylinder Head-Bolts (Refer to 9 - ENGINE/CYLINDER HEAD - INSTALLATION) Cylinder Head Cover-Bolts 12 - 105 Flex Plate to Crankshaft 88 65 - Engine Mounting (Refer to 9 - ENGINE/ENGINE MOUNTING) Powertrain Torque Strut 54 40 - Exhaust Manifold-Bolts 23 - 200 Exhaust Crossover Pipe-Bolts 54 40 - Intake Manifold - Lower-Bolts 23 - 200 Intake Manifold - Lower Gasket Retainer-Bolts 12 - 105 Intake Manifold Upper-Bolts 12 - 105 Lifter Yoke Retainer-Bolts 12 - 105 Oil Filter Attaching Fitting 54 40 - Oil Cooler Attaching Fitting 27 20 - Oil Filter 20 15 - Oil Filter Adapter-Bolts 28 - 250 Oil Gallery Plug 27 20 - Oil Pan-Bolts 12 - 105 Oil Pan Drain-Plug 27 20 - Oil Pressure Switch 23 - 200 Oil Pump Cover Plate-Screws 12 - 105 Oil Pump Pick-up Tube-Bolt 28 - 250 Oil Dipstick Housing-Bolts 48 35 - Rocker Arm Shaft-Bolts 23 - 200 Spark Plug 16 12 - Thermostat Housing 12 - 105 Timing Chain Case Cover -M8 Bolt 27 20 - -M10 Bolt 54 40 - Water Pump-Bolts 12 - 105 Water Pump Pulley-Bolts 28 - 250
Should you need extra help visit my website here: http://www.bigasautorepair.com/

do a compression test , check for cracked manifold .

this may be due to an oil leak getting onto the manifold or the manifold is cracked and exhaust gas is building up in the engine.

if smoke is intence and black this indicates oil.
if it is mid and grey blue this indicates exhaust gas


get checked by a mechanic


i hope this was useful.

The classic signs to look for are engine over-heating with bluish-grey smoke from the exhaust pipe and it might be smoking excessively, look for coolat present in the engine oil, the engine oil will float on top of the coolant so if the engine oil is reading unusually high on the dip-stick you can loosen the engine oil drain plug just enough until it starts to drip fluid, and if that fluid is water or coolant then you might have a blown head gasket or an intake manifold leak, and if you have all of the symptoms of a head gasket without the smoke from the exhaust pipe it might just be the intake manifold.

Right-Hand
Removal

1. Remove spark plug heat shield (12A406).
   

1. Remove distributor to spark plug wires (12286) using Spark Plug Wire Remover T74P-6666-A.
   
1. Disconnect muffler inlet pipe.
   
1. If equipped with secondary air injection, disconnect the secondary air injection check valve tube (9B480).
   
1. Remove attaching bolts and right exhaust manifold (9430).
   
1. Inspect joint faces for signs fo exhaust leaks, cracks or any defect that would make exhaust manifold unfit for use
   

Left-Hand Removal






1. Remove oil level indicator tube (6754).

1. Remove spark plug heat shield.
   

1. Remove distributor to spark plug wires using Spark Plug Wire Remover T74P-6666-A.
   

1. Disconnect EGR valve to exhaust manifold tube (9D477). If equipped with air injection, disconnect the secondary air injection check valve tube.
   

1. Disconnect muffler inlet pipe.
   

1. Remove attaching bolts and exhaust manifold (9431).
   

1. Inspect joint faces for signs of exhaust leaks, cracks or any defect that would make the exhaust manifold unfit for use.
   

Installation

1. Clean mating surfaces of right exhaust manifold or left exhaust manifold and cylinder head (6049). Clean mounting flange of right exhaust manifold or left exhaust manifold and inlet pipe(s). Clean mounting surface for air injection tube or right exhaust manifold. Apply light film of Premium Long-Life Grease XG-1-C or -K or equivalent meeting Ford specification ESA-M1C75-B to right exhaust manifold or left exhaust manifold.
   

1. Position right exhaust manifold or left exhaust manifold on cylinder head. Install attaching bolts and washers, starting at fourth bolt hole from front of each right exhaust manifold or left exhaust manifold. Tighten bolts to 34-47 Nm (25-35 lb-ft), working from center right to both ends.
   
1. Position inlet pipes to right exhaust manifold or left exhaust manifold. Install attaching nuts and tighten to 34-47 Nm (25-35 lb-ft).
   
1. Position the secondary air injection check valve tube and the secondary air injection tube gasket (9C435) at rear of right-hand exhaust manifold. Install attaching bolts and tighten to 19-25 Nm (14-18 lb-ft).
   
1. Attach the secondary air injection manifold tube (9B449) to left-hand exhaust manifold fitting (located under EGR tube). Tighten nut to 30-40 Nm (22-30 lb-ft).
   
1. Attach the secondary air injection check valve tube to rear of right-hand cylinder head. Tighten bolts to 75-85 Nm (56-62 lb-ft).
   
1. Connect EGR valve to exhaust manifold tube to left exhaust manifold, if removed. Tighten nut to 53-72 Nm (39-53 lb-ft).
   
1. Install spark plug heat shield and distributor to spark plug wires.
   
1. Install oil level indicator tube to left exhaust manifold, if removed. Tighten nut to 13-24 Nm (10-18 lb-ft).
   
2. Start engine (6007) and check for exhaust leaks.
   

Hope this helps you...WF †

yes it could.... check the oil for traces of foaming...that would indicate water leaking via a crack.
Also check for oil in the water reservoir.... sign of cracked head also...

where is oil pressure switch/sensor on 2001 nubira

Either the cylinder head is cracked or, Is it possible that a stud had once been broken off in the hole(s) and when they were drilled out the drill went a bit to deep and punctured the cylinder head? That is about the only reason their would be oil coming out of the manifold stud holes as the holes are not connected internally to anything.