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Needle lift sensor - - - part of the No.3 injector
radiator fan - - - - - - big whirly spinny thing at the front
Probably means the fan speed controller? Under the battery tray, I think.
accelerator pedal - - porobably means the sensor, connected to the pedal by a rod.
quantity adjuster - - - inside the diesel distribution pump.
modulation piston sensor - inside the diesel distribution pump.
The last two are part of the diesel pump itself, and I don't think they are diy-replacable
radiator fan - - - - - - big whirly spinny thing at the front
Probably means the fan speed controller? Under the battery tray, I think.accelerator pedal - - porobably means the sensor, connected to the pedal by a rod.
quantity adjuster - - - inside the diesel distribution pump.
modulation piston sensor - inside the diesel distribution pump.
The last two are part of the diesel pump itself, and I don't think they are diy-replacable
This will give you chapter and verse on where these components are.
Now as far as I know the fuel filter is on the inner wing of the car. The injection pump is the big metal lump with four fuel pipes coming out of it, going to the injectors. It's driven by the toothed belt and sits in front of the engine block. I wouldn't have said it was near the fuel filter.
In these engines (TDI 90 and 110) there is no other fuel pump, just the mechanical distribution pump. PD engines have two pumps, a fuel lift pump in the tank and the circulating pump driven off the camshaft. Fuel delivery to the injectors is relatively low pressure, the high pressure is generated by the PD injector itself.
Now as far as I know the fuel filter is on the inner wing of the car. The injection pump is the big metal lump with four fuel pipes coming out of it, going to the injectors. It's driven by the toothed belt and sits in front of the engine block. I wouldn't have said it was near the fuel filter.
In these engines (TDI 90 and 110) there is no other fuel pump, just the mechanical distribution pump. PD engines have two pumps, a fuel lift pump in the tank and the circulating pump driven off the camshaft. Fuel delivery to the injectors is relatively low pressure, the high pressure is generated by the PD injector itself.
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that information is very helpful at explaining everything. thanks
was checking the pipes running from injector to injector and they are in bad shape.
do you know where i can get replacement pipes.
also, there was a diesel leak on top of fuel filter, so i got replacement black t piece which inserts into fuel filter and pipe either side, must be return pipe to tank.
anyway................ £18.75.............. wow
was checking the pipes running from injector to injector and they are in bad shape.
do you know where i can get replacement pipes.
also, there was a diesel leak on top of fuel filter, so i got replacement black t piece which inserts into fuel filter and pipe either side, must be return pipe to tank.
anyway................ £18.75.............. wow
Injector - to - injector - - - must be the fuel return pipes. Dealer, independent, VAG parts dealer come to mind. This is on the low pressure side of the fuel circuit, so the demands are low, generic diesel tubing may well do.
The item on top of the fuel filter is the regulating valve, a flow limiter to make sure that there is always a little back pressure in the pipes to stop air bubbles creeping in from the return sysem
The item on top of the fuel filter is the regulating valve, a flow limiter to make sure that there is always a little back pressure in the pipes to stop air bubbles creeping in from the return sysem
Hold on - - - we are talking about a distributor pump engine, TDI 90 or 110, which does not have fuel lines between the injectors. Do you mean the tubing between the pump and the injectors?
Digging further I can find that the connections between each injector and the fuel return line are called injector bleed hoses. I'm not sure what they do, though, as this is not a common-rail system and there isn't a normal reason for fuel to be returned from the injector. The fuel quantity is measured and timed at the injector pump, nothing should be rejected at the injector.
Guessing, maybe it is an emergency bypass in case the injector jams shut, or perhaps a system for allowing air bubbles to escape.
Anybody else out there know the answer?
Guessing, maybe it is an emergency bypass in case the injector jams shut, or perhaps a system for allowing air bubbles to escape.
Anybody else out there know the answer?
today, checked my actuator controlling turbo. wd40 and freed up. the actuator rod pulls down with vacuum from pipe, to close turbo. this happens when engine is running, until it needs to boost, when it releases and turns on turbo.
am i right?
anyway, removed the pipe connected to actuator and turbo is on all the time, so no limp mode, would this cause any damage to car/turbo.
am i right?
anyway, removed the pipe connected to actuator and turbo is on all the time, so no limp mode, would this cause any damage to car/turbo.
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nathal wrote
today, checked my actuator controlling turbo. wd40 and freed up. the actuator rod pulls down with vacuum from pipe, to close turbo. this happens when engine is running, until it needs to boost, when it releases and turns on turbo.
am i right?
Not really.
The vanes are spring-loaded towards the open position, which is the position for max gas flow through the turbine, corresponding to maximum engine rpm. When the engine starts, the ECU applies vacuum to pull the vanes to the narrow-opening position. The restricts the turbine entry which makes the relatively small amount of exhaust gas go faster.
Small amount of gas, narrower opening = faster gas flow.
The faster gas flow spins the turbine up to a rate where it produces useful boost, despite the low mass of gas flow through the engine.
It isn't an on-off switch, and the aim of the very carefully designed variable vanes in the turbine inlet is to get the turbine spinning fast at the lowest possible engine rpm (= amount of exhaust gas) and produce usable boost from low down. The ECU gradually opens the vanes as revs rise to keep the turbo producing max boost over the widest possible rev range.
anyway, removed the pipe connected to actuator and turbo is on all the time, so no limp mode, would this cause any damage to car/turbo.
Actually your turbo is off all the time, the system is designed to fail safe, so the default position is minumum boost. You aren't getting enough boost to put you into limp mode: but you should notice that the car is down on power.
today, checked my actuator controlling turbo. wd40 and freed up. the actuator rod pulls down with vacuum from pipe, to close turbo. this happens when engine is running, until it needs to boost, when it releases and turns on turbo.
am i right?
Not really.
The vanes are spring-loaded towards the open position, which is the position for max gas flow through the turbine, corresponding to maximum engine rpm. When the engine starts, the ECU applies vacuum to pull the vanes to the narrow-opening position. The restricts the turbine entry which makes the relatively small amount of exhaust gas go faster.
Small amount of gas, narrower opening = faster gas flow.
The faster gas flow spins the turbine up to a rate where it produces useful boost, despite the low mass of gas flow through the engine.
It isn't an on-off switch, and the aim of the very carefully designed variable vanes in the turbine inlet is to get the turbine spinning fast at the lowest possible engine rpm (= amount of exhaust gas) and produce usable boost from low down. The ECU gradually opens the vanes as revs rise to keep the turbo producing max boost over the widest possible rev range.
anyway, removed the pipe connected to actuator and turbo is on all the time, so no limp mode, would this cause any damage to car/turbo.
Actually your turbo is off all the time, the system is designed to fail safe, so the default position is minumum boost. You aren't getting enough boost to put you into limp mode: but you should notice that the car is down on power.
well, problem is cured at high revs.
no more limp mode, turbo's out to the max
i get an odd limp, when at low revs when car is cold.
i fixed the problem, by spraying CONTACT CLEANER on all the electrical plugs and round maf and plug.
also, had ordered replacement vacuum pipes, so i changed them afterwards,, as i had got them
no more limp mode, turbo's out to the max
i get an odd limp, when at low revs when car is cold.
i fixed the problem, by spraying CONTACT CLEANER on all the electrical plugs and round maf and plug.
also, had ordered replacement vacuum pipes, so i changed them afterwards,, as i had got them
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