Hi, I have a 1998 Toyota Hilux Dbl Cab - 2.4L TD EFi Engine and recently I encountered an intermittant performance problem. Basically the van stalls when revved over 2000 rpm. This issue mostly affects uphill driving making my Toyota go at 15 Km/h even when floored and on occurance persists also on normal plain roads. No engine/diagnostic lights are switching on the Dashboard. What I have noticed is that the fuel primer button/lever on top of the fuel filter (primer head) becomes very loose (no pressure) and falls to the down position as if there is some airleak/vaccum however goes back up to normal position after I switch off my toyota for a couple of minutes. The funny thing is that if I remove the fuel filter outlet pipe, press the primer button a couple of times (diesel squirets out) and reconnect the pipe again, the engine performance comes back to normal for a few minutes. I tried changing the filter and eventually helped delaying the problem however the issue is still present. Does anyone have any idea of what the issue might be - any suggestion would be greatly appreciated? (IMG:style_emoticons/default/sad.gif)

Sounds like it may be starving for fuel, make sure your tank is not holding a vacuum (make sure the tank breather is clear), failing that make sure there isn't a water seperator between the tank and the priming head (some vehicles have them and I can't remember if Hilux have them too!!), if so remove it and either clean it out if it is servicable, if not replace it. Failing that you might have some crap in your fuel lines or in your fuel tank pickup, REMOVE THE FUEL CAP FIRST then remove the hose that comes from the tank at the filter and blow back to the tank using LOW pressure compressed air or if you don't mind the taste of diesel :) blow through the fuel line, if you can get air through it then it isn't blocked! Also wouldn't hurt to change the filter on the priming head (if you have crap in your fuel it will be in there too!!). Another thing, get a decent sized drain tin under the drain plug of the fuel tank and remove the plug carefully, if there is any water coming out with fuel (you only need to drain about a litre to find out this), then you need to get your tank drained and cleaned out and all your fuel filters changed, (don't put methylated spirits in your tank to assorb the water, that may do serious damage to your engine if you put too much in!! :( ) You can tell if there is water in your fuel because it will turn to balls under the diesel in your drain tray. If you have algae in your tank (usually that stuff blocks filters really quickly and looks grey to black in colour), you need to get some biocide to kill it and preferably get your tank cleaned out and all fuel filters changed.
Above all else if you are unsure about anything that I have said above seek the advice of a qualified diesel mechanic, they work with diesels all the time and usually have a pretty good idea what is going on!! :)

Best of luck,
Mechdave...