я тут нашел на буржуйском сайте похожую проблему, ниже приведу цитату без перевода. Возможно, правда, что у него схема от более нового прадика и у нас она не работает. И кстати, там дизель.
Суть в том, что топливо из доп.бака в двигатель не поступает вообще. А идет в конструкцию бензонасоса в основном баке, где через клапан Вентури уже передается в магистраль. Грубо говоря, клапан - это тройник с двумя входами от топливных насосов и одним выходом.
Если клапан этот начал подтравливать, то пошел подсос из основного бака в магистраль на недостаток давления. Возможно, даже, что травит на каком-то давлении, и при плавной езде давления хватает, а при подгазовке идет подсос.
Найти бы схематичную понятную блок-схему соединения всех трубок и клапанов...
Hello all
I have resolved the problem, so here are the symptoms and solution for anyone to learn from.
The problem was the fuel pump which is in the main tank(central underbody one). This pump does nothing except pump fuel out, through another fuel filter (underbody, next to main tank - small black one)and back into the same main tank, passing through a venturi valve at the same time. This pump and venturi valve are all in the same pump housing inside the tank.The assembly/housing also has a fuel level switch attached as well.This pump runs all the time your motor is on. Its only function is to pass fuel through the venturi valve, which creates a suction, sucking fuel from the back tank to the front tank. It does not pump fuel to the front filter or the injector pump. The motor sucks fuel only from the front/main tank. If the pump in the main tank stops working (or the inline fuel filter that it runs through is blocked - as another writer suggested) then there will be no fuel supplied from the rear tank and sooner or later the front tank will run dry. When that happens, the motor stops. There must be two fuel gauge senders, one which shows when the rear tank has no fuel. When you finally figure out that you have run out of fuel, despite your gauge showing that you may have say half a tank - the first thing you do is fill up - probably both tanks. When you do this, the back tank remains full and the motor drains only the front tank. 90 litres or so later you will run out again, despite there being 90l in the back tank. To make things worse, when you go to the garage to fill up, the bowser will not take any fuel - just goes into blowback mode. The reason is that the main fuel vent relief runs between tanks and with the back tank at peak level , the airflow is blocked(fuel blocks it). Thus you can't put fuel in, because you can't get any air out. You can trickle fuel in with a jerry can to get by and get you moving. Apparently you can get a replacement pump $700-800 or you replace the whole unit - about $1200-1300(all plus labor).I decided to replace the whole assembly. The smart thing for Toyota to do would have been to have the pump as an inline pump mounted externally. So if it failed it could easily be replaced , particularly if you were in a remote location. It is probably possible to trace the lines and install an inline pump externally, but I did not have time or incentive to do this. If you were taking a Prado into the outback I suggest you do this - or take a spare pump(as well as spare fuel filters). It would not be an easy job to get the small pump out of the whole assembly, just because it is fiddly. It is not much good going to Toyota as after three of the main dealers in Perth, they did not know how the fuel system works, that the vehicle actually had two fuel filters or why the symptoms were happening. It is not hard to replace the fuel pump assembly - just drop the main tank, making sure you don't get the lines confused, remove the pump from the tank and put the new one in, hook it all up again and all should be good.
Update: нашел на форуме, что именно такая схема на 120-х. Но вот в каталоге запчастей на 95 вообще никаких заморочек - показан голый бензонасос и короткий патрубок для цепляния к магистрали.
Тогда остается вопрос, где фишку снимать.
Автор
Тема: начала падать стрелка бака при езде на втором. (Прочитано 4096 раз)
