Thread: Measures to combat a runaway diesel engine

Originally Posted by voksboy

Exactly, when this was happening we all just wanted to jump out of my rig. If my kid was there or my wife was driving. I have 2 turbo diesels for daily drive. I had no idea what a run away diesel was and even if I read it in a forum I wouldn't have cared.

This may be rare but when it happens hope you're prepared. Thankfully mine was a manual and I'm experienced and didn't panic. Basically got lucky and was able to kill the car.

Now for a new turbo or upgrade an secondly find a cure.

I didnt know how or to stall the engine dead....plus the fact there was another car right behind me.....I knew what I was going to do was not going to end well. I depressed the clutch and keep trying to shut it down, while braking and pulling over as much as I could.

The rest is history

Originally Posted by voksboy

I would like to know how to prevent this from ever happening again. what if my wife was driving. Her car is an automatic turbo diesel pajero. Also my cars are maintained quite well

Tell her to put it in neutral, stop, put on the handbrake and walk away.

I still think something like a Commodore V8 throttle body grafted into the air intake would be useful and cheap insurance against runaways. Big red knob on the dash, push for emergency stops.

Originally Posted by bee utey

I still think something like a Commodore V8 throttle body grafted into the air intake would be useful and cheap insurance against runaways. Big red knob on the dash, push for emergency stops.

Yes. Some of the Jap diesels had a mechanical butterfly thingy that was used on some of the electronic control pump IDI engines for some obscure reason, so you could use one of those with a pull cable. TD27T from the Terrano 1 comes to mind.

Originally Posted by jakeslouw

Yes. Some of the Jap diesels had a mechanical butterfly thingy that was used on some of the electronic control pump IDI engines for some obscure reason, so you could use one of those with a pull cable. TD27T from the Terrano 1 comes to mind.

I saw one on a Toyota Hilux circa 2000 NA diesel engine, a bit small for a turbo but was solenoid operated, went closed with the ignition off.

Thought I'd throw in my two bob's worth, for what it's worth. I've seen one runaway diesel: a 300Tdi. The vehicle had been rolled and when I arrived to check it out a local "mechanic" had already restarted the engine. I had been planning to check and see where all the oil had got to before sorting it out and attempting to restart anything. The bloke proudly started revving the engine hard to show me all was well, and as I was in the process of yelling at him to warn him not to do it, the engine took off like a 747. It howled like a banshee, louder and louder and higher and higher and I stuck a (very nervous) hand into the engine bay to pull off the fuel solenoid wire, then ducked into the driver's seat, put the vehicle in fifth, planted my right foot on the brakes and let out the clutch. Luckily, it stalled.

The old bloke's face had changed colour by this point. A few minutes later, the owner appeared and I had to explain what had happened without inciting any murders (which was not as easy to do as it is to write).

When the vehicle was (oh so tentatively) restarted later, there was a nice knock in the motor.*

I never worked on that engine later, and I was never aware of any proper diagnosis of the problem - but it definitely ran away like a cheetah on benzedrine.

* Funnily enough, I heard later that when it was stripped there was no damage found. It had sounded to me like there was a dwarf in the sump swinging a large hammer to attract attention from passers-by......

Originally Posted by jakeslouw

Yes. Some of the Jap diesels had a mechanical butterfly thingy that was used on some of the electronic control pump IDI engines for some obscure reason, so you could use one of those with a pull cable. TD27T from the Terrano 1 comes to mind.

Early emissions control, throttles the engine a little to reduce NOx at part load. Also works with EGR on some engines and for a softer shut-down.

If you let air into the fuel line a diesel will normally stop. Do not know how tou would dothis, but you could stop the motor this way.