I have a 1997 Galant VRG. When driving at low speed and turning either way, I hear a thumping sound from the engine now and then. Sounds like a minor explosion and seems to come from the lower end of the engine compartment. What could be the problem?

o2 sencer

Legnum?
Mitsubishi Legnum????
Mitsubishi Aspire
Mitsubishi MX/MF
Mitsubishi VRG
Mitsubishi VRM (Hong Kong)
9 engines offered, day 1.
and many trans,
4-speed automatic
5-speed manual
5-speed semi-automatic

Mitsubishi F4A23-2; 4 Speed
KM175, KM176, KM177 - F4A21-2 (176-5), K4A22-2 (175-5), F4A23-2 (177-8); ES Model
41TE
F4A33-1
the truth is , you didnt post country, nor engine size.
they match engine power to transmission (load rating)
so>? forget that.. that is for later.
IT DIED< so if the engine dont START the tranny issues are moot.
so does it crank.????
if it cranks , it next needs spark got spark to all cylinders.
that is if its not the Diesel engine, IS IT??

pressure guage should stay after you turn-off the ignition switch. check also if your engine has a cold start injector. it may be restricted.

Have the wheel bearings been checked?

The cause is too low an idle and engine is starving for fuel so it shakes like that.The thumping sound you hear is most likely just the exhaust being too close to the floor amd bumping against it when in drive with brake on.You said yourself that it stops when you put it in nuetral,well the engine speed goes up when there's no stress on it.With some one holding the brake and it's sitting there thumping,set the idle speed up just enough to make the engine stop rocking that way.

SMOKING BLUE YOU HAVE LOW COMPRESSION ENGINE BURNING OIL.YOU HAVE WORN VALVE GUIDES ALSO VALVE SEALS AND WORN PISTON RINGS.

Hi,

The capacity of the tank is 55 liters.

Thanks

Jason

check the drive axles and hub bearings checked

You may find it's either a worn CV joint or it may just need greasing up.
Check the bellows for splits, and if OK you can cut the large band that holds it in place, pull it back and check for grease, fill with grease and reattatch using a tie-strap.

Can you tell if your car is a GDI or MPI? What do you mean by buking? Can you describe the problem a little bit more...like when it does it cold or hot full throttle or slow openings?