Engine knocking and very hot

[charless82]

I was wondering if anyone can help me pin point the fault in my 2007 infiniti G35 sedan. after driving for about 30mins or so I hear a knocking sound from the engine on 1-2gear low rpm. the engine also seems to be running on high heat but the temp gauge seems normal.

[telcoman]

I was wondering if anyone can help me pin point the fault in my 2007 infiniti G35 sedan. after driving for about 30mins or so I hear a knocking sound from the engine on 1-2gear low rpm. the engine also seems to be running on high heat but the temp gauge seems normal.

Welcome to NICO

Did you check your oil and coolent?

[charless82]

Yes, Oil is down by 1/2 litre AND coolant is full....could it be a water pump ?? ive just had the thermostat changed thinking that was the issues but problem still persist...i get the occasional backfire and sluggish drive.

[charless82]

Alright new twist, i opened the radiotor cap and realized it didn have a pressure spring underneath the cap but the reservoir tank had the spring thingy on it so decided to switch them around. So drove round town for about 45 mins with the A/c on and then toward the last mile to my destination i decided to switch off the a/c. when i got to my garage and switched off my car after a few revs the water started pouring out of my reservoir tank erracticly and i could hear the water boiling.
Now do you thing this is because i switched the caps around or is there a bigger problem to this....keep in mind the knocking or rattling is still there and i think this may be somehow connected.

PLEASE HELP HELP HELP !!!

[telcoman]

Yes, Oil is down by 1/2 litre AND coolant is full....could it be a water pump ?? ive just had the thermostat changed thinking that was the issues but problem still persist...i get the occasional backfire and sluggish drive.

You never mentioned what your temperature gauge was reading or who changed the thermostat.
Was the work done at the dealer? I suspect not.
In any case it sounds like you've got an air bubble in your coolent system and perhaps an incorrect thermostat and an incorrect radiator cap?

If it was me I'd bite the bullet and call AAA to send a flatbed tow truck and take it to your Infiniti dealer. Unless you had a Infiniti thermostat installed have that replaced, a coolent flush and a new radiator cap. They can also test the water pump.

They will not allow you to drive away with air bubbles in your cooling system.

I hope you didn't ruin your engine

Enjoy their loaner and whatever free food they have.

Good luck!

Telcoman

[audtatious]

I agree with Howie above. Check for an air bubble first then proceed to look at the thermostat, etc. While it's doubtful you have a clogged radiator it's always possible as well.

[Captain Obvious]

i got to my garage and switched off my car after a few revs

Why would you rev the engine before shutting it off? You want it to be cool as possible when you shut it down, let it idle for ten seconds before turning it off to get the extra heat from driving out of the block.