[thekNack]

Hi Guys

I just wanted an opinion on weather I should be worrid or not. For a while now my engine light has been coming on at low altitude. When we go to the coast or Kruger Park. Sometimes the engine also dies when I take my foot off the accelerator. This problem however goes away when I disconnect the vacuum pipe that throttles the engine. I forget what the thing is called but It is supposed to kill the engine when you want to switch off. when I disconnect this pipe the problem does nto occur.

that is some background. the last two times I have been to Kruger I noticed excessive smoking after being there about 4-5 days. Once I get back on the highway it takes about 100kms then it stops. However this usually means I am also back at altitude.

Is this caused by bad fuel? (water in the diesel?)
Driving slowly so much?(50km/h or less for a week)
Altitude?
None of the above

Should I worry about this if it goes away at high speed? My engine is at 235 000kms, doesn't feel like any performance issues.

Thanks!

C

[CATS]

Maybe check for any faultcodes with the DIY method.

If it stalls it should register something.

CATS

[Nick Gibson]

The engine dying while idling could be the vacuum operated butterfly valve in you intake manifold that is poorly adjusted. There is a set screw to adjust how much it closes the valve when the engine is at operating temperature. It's purpose to close the valve partially to assist the EGR in operation and reduce engine vibration at idle.
The Top vacuum actuator on this butterfly valve is for EGR and idle(closes about 85%), and the bottom actuator is to close the valve 100% to prevent prolonged engine shudder at shutdown.
See picture below:

Valve.PNG (14.65 KiB) Viewed 872 times

Ps.
Is your egr system disconnected or blanked off?
What colour is the smoke from your exhaust, black, white or blue?

EDIT: Neatened up the post and added screen shots.

[thekNack]

thanks for the feedback. I am pretty sure it is the butterfly mechanism that causes the problem with idling. On a previous post Marius did explain removing the vacuum hose to solve the problem. I ahve however not tried adjusting as mentioned in this reply. This could very well solve the problem as it may just be poorly adjusted for low altitude conditions.

the smoke that results from game driving is black. I was wondering if it has something to do with either the slow driving or me removing the vacuum pipe. I thought this could result in un-burned fuel staying behind or something.

I will have a look at the screw and the EGR feedback.

Thanks again.

C