I have a 03 Mitsubishi Montero Sport 3.0 L. I have constant knocking from the engine


#1

Once in a while the car won’t even attempt to start. All you hear is a click, then one or two more tries and the car starts. When idling the knocking can be heard, or when i push the gas the knock can be heard. I was once told it could be that the spark plugs are going bad and it is causing a issue with the pistons. Any one have an idea as to my issue. Every so often the knocking will go away completely. Also with the car not staring it is not like you hear the car try to start, it is just a click and nothing else.

New here so please advise if i can improve question.


#2

The clicking you hear is probably due to bad contacts in the starter solenoid (part of the starter).

The fact that the knock clears up intermittently may indicate a sticking hydraulic valve lash adjuster. Have you kept up with your oil changes? Inadequate oil changes can cause this.

The two problems are unrelated. I seriously doubt it’s spark plug related.


#3

Thank you for your response. I have been keeping up with oil changes however the mechanic my father usually takes us to has said that perhaps the car needs a new starter. Once again thank you for the response.


#4

Also a starter can be check to see if it is bad correct?


#5

A starter can be bench tested.

As far as the knock is concerned, is it more of a ticking-clicking noise? Or is it a dull deep knocking noise? A ticking-clicking noise would point to a valve lash adjuster. Other knocks are not usually intermittent.


#6

The proper diagnostic method for the no-crank problem is a voltage measurement at the starter motor during attempted cranking. That way the causes can be differentiated among the starter motor, battery, connections, grounds, relays, ignition switch, etc. If you want to skip the diagnosis and make a guess, the easiest thing for a diy’er that quite often actually works for this problem is to clean the battery posts and terminals and make sure the connections there are tight.

If you are actually hearing an engine “ping” – as opposed to a “knock” – that be caused by spark plugs whose gaps have opened too wide and need to be replaced. Pings, which can be caused by other things than just spark plugs, usually get noticeably worse during acceleration or when going uphill.


#7

Sure wish we could hear a video/audio of the knock. It would really be a rarity for an engine to ping while idling. I actually heard this happen once about fifty years ago when working at a Citgo station. Turned out to be a small incandescent carbon deposit on a spark plug.


#8

If the engine truly has a bottom end knock, that does not bode well :trollface:


#9

It could all be due to the starter. Bad contacts cause the to crank issue, but also when the engine does start, the starter might not be retracting completely causing the knocking sound. I thin you should replace the starter first and see what happens.