Engine knock ,top left corner of 3.0 engine - 1994 Plymouth Voyager

I think above starter is it a sensor with a center bolt (Knock sensor)
Some engine had cam sensor in place where was the distributor at the end of intake manifold in bloc

If the knocking sounds like thudding or something dull is knocking on the car, remove the left front wheel and check the drive shaft boot. It could have been torn and parts of it is hitting the lower arm. If it comes from the engine, check the engine mounts, all 3 of them.

i have the same problem. KNOCKING. Appears alot of others are having this problem. Sounds like some kind of recall needs to be done!

1. Knock sensor. Check all the wiring connections on the engine heads. Your sensor probably is failed (but see Overheating #3 below) .
2. fast blinking left turn signal. The front bulb has failed, so replace it.
3. oil temperature light. This may be an indirect result of #1, as the engine is not running properly and this can cause overheating (but see Overheating #3 below)

Other causes of overheating ...

1. low oil level
2. low coolant level. If you are losing coolant, the cause has to be located. The correct fill method is to top up the radiator, then repeatedly squeeze the top rad hose, to "burp" all the air out of the cooling system. You will hear the coolant squishing in the top of the engine. Keep burping until the coolant squishing noise stops.
3. head gasket(s) may be failing, a not uncommon problem for your engine model. Check for oil in the coolant.

SD

It's a common problem with these cars i am actually fixing mine as of now. That car is all about oil pressure and when it is low you'll start to get a tap and or what sounds like a knock due to the lifters not having enough pressure. Try taking your oil pan off and check your oil pick up line going from the oil pan to the turbo. A lot of times it gets a lot of sludge build up and makes the pressure little to none. If that looks clear check the slump inside the oil pan and see if that has sludge build up. Well hope this helped

3.0L Engine

1. Before servicing the vehicle, refer to the precautions section.
2. Disconnect the negative battery cable.
3. Drain the engine coolant.
4. Remove or disconnect the following:
   Wiper and blade assembly Top cowl seal and panel Window washer hoses, from the ventilator louvers Left and right ventilator louvers Heater air duct Timing belt
5. Mark the left and right camshaft pulleys with a touch of paint.
6. Remove or disconnect the following:
   NOTE Be sure not to mix up the pulleys.
   Right and left camshaft pulleys bolts Pulleys from the engine
   No. 2 idler pulley by removing the bolt 3 clamps and engine wire from the rear timing belt cover 6 No. 3 timing belt cover-to-engine bolts Water pump nuts/bolts Water pump and gasket from the engine
   
   
   Fig. Exploded view of the components to gain access to the water pump-3.0L engine
   
   
   
   Fig. Exploded view of the water pump and related components-3.0L engine
   

To install:

1. Check that the water pump turns smoothly. Also check the air hole for coolant leakage.
2. Apply liquid sealer to the gasket, water pump and engine block.
3. Install or connect the following:
   NOTE After tightening the bolt, be sure the idler pulley moves smoothly.
   NOTE Be sure to align the knock pin hole on the camshaft pulley with the knock pin on the camshaft.
   NOTE Be sure to align the knock pin hole on the camshaft pulley with the knock pin on the camshaft.
   Water pump, using a new gasket. Tighten the nuts/bolts to 53 inch lbs. (6 Nm). Rear timing belt cover. Tighten the 6 bolts to 74 inch lbs. (9 Nm). Engine wire with the 3 clamps to the rear timing belt cover No. 2 idler pulley. Tighten the bolt to 32 ft. lbs. (43 Nm).
   Right-hand camshaft pulley, with the flange side outward.
   Tighten the camshaft bolt to 65 ft. lbs. (88 Nm), using the removal tools Left-hand camshaft pulley, with the flange side inward.
   Tighten the camshaft bolt to 94 ft. lbs. (125 Nm), using the removal tools Timing belt
   
4. Fill the engine coolant.
5. Install or connect the following:
   Heater air duct Left and right ventilator louvers Window washer hoses to the ventilator louvers Top cowl seal and panel Wiper and blade assembly Negative battery cable
6. Start the engine.
7. Top off the engine coolant and check for leaks.

Hope this help.

my Hyundai 'Tucson 2006 had a leak today when I came out from work. I don't know about cars but i'm curious enough to open the engine top to see what's going on. And I found a piece just lying there, It's the same as the top to check the oil, has a yellow plastic part says A/C oil. I couldn't find where it goes or what it is.

Facing engine from the front of the car.
No. 1 goes to top left
no.2 goes to bottom right
no. 3 goes to top right
no 4 goes to bottom left

The knock Sensors are located under the Intake Manifold at the top of your engine. The top will have to be taken off along with the intake manifold. Knock Sensors in past silverados used to have a problem with leaking water that corroded the sensors from washing the engine. Most times when you go to replace the knock sensor you will have to replace both along with the wiring harness that includes the the gaskets the knock sensors are surrounded by. After that you have to check the resistance to make sure you dont have any problems and then reinstall all parts along with a new intake manifold gasket. A good mechanic can do this for you in a day and charge you around $400. If you try to go to some place like a chevy dealer you will pay over $800. This is from experience of just replacing mine 2 weeks ago.