Vehicle in question is my '00 Pajero with a 12-valve 6G72. I was driving home this evening, and had to merge with fast traffic on the highway. I floored the gas pedal and whilst the engine was at 5,000 rpm there was a loud bang, almost as though the muffler burst. Following this, the engine rpm dropped momentarily to 1,500 and then down to 0. Worthy of note, no warning lights (such as oil pressure or battery) came on when the engine died. I safely pulled to the side, and tried restarting the engine...it turns over but does not start.

It doesn't sound different at all when it turns over, it's the same...except the engine does not start. It doesn't crank faster or anything like that. I reckoned it could be a snapped timing belt, but I religiously change it ever 50,000 miles and I reckon it would crank faster if it snapped. Any help will be appreciated, thank you.

 

I would first check the timing belt.

If that is okay, then I would start to check for spark and fuel.

 

As silly as this will sound, the high tension cable came off the ignition coil. How that happened, I haven't a clue. Replaced it, and she fired right up. Unfortunately, the battery wasn't charging though, and it turned out the alternator's time had come. After a $120 charge to rebuild it, I was sorted.

 

Congratulations on an easy fix.

 

Thank you! I was rather pleased indeed, especially as I was expecting a hefty bill for a top end rebuilt!

 

Quick question, if anybody can help me out. After this problem was sorted out, I started to notice a problem when the engine is cold. When the engine is cold, and you give it some gas, it bogs down. The rpm drops to zero-ish and then goes up to whatever the rpm should be at that throttle position. It's as if the engine died, and came back to life with a higher rpm. Once warmed up, the problem goes away. Any idea what could cause this? Could it be the spark plugs? Dirty injectors?

Worthy of note, the distributor rotor, cap and ignition cables (all OEM) have 32,000 km (20,000 miles) on them and the spark plugs (NGK BPR6E-11) have 19,000 km (12,000 miles) on them.

 

That is an ignition issue. I would say make sure one of those isn't bad by checking the resistance of the spark plug wire with a multi meter.

Also make sure the plugs are gapped correctly.

 

Probably dirty injectors or soft carbon on the back of the intake valves. Try running some injector cleaner and going to a fuel with cleaner in it. Although maybe not soft carbon the way you are WOT.

Just recently fixed a Galant with 200K mi. Had to replace all 4 injectors (and fuel filter), a clean didn't help.

 

Thank you for the responses. I'll run a quart of Marvel Mystery Oil when I have a quarter tank of gas and see if that solves the issue, before diagnosing the ignition system and checking the plugs.

NWM_Tech, is 30,000 miles a reasonable interval to change a fuel filter? Mine is at 20,000 miles at the moment, and I'm wondering if I'm keeping it for too long. Also, I run 87 AKI in this engine (as recommended), would a switch to 91 help or just be wasteful? Thanks!