Offroader
Mit dabei seit Mitte 2005
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 Verfasst am: 27.08.2006 22:50:24 Titel: |
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Noch mehr Lösungsansatz - liest eigentlich noch wer mit?
| ariane44 hat folgendes geschrieben: | A partial answer.
In early cars the air flow is calculated from the combination of the MAP sensor and the IAT sensor.
Later cars lost the IAT but kept the MAP, also having a Mass Air Flow device bolted to the outlet of the air filter box,
so it's very obvious. Temperature sensing is part of the MAF.
I haven't had any tickover problems on my engine, and if your engine doesn't have EGR the crankcase breather is the same
as mine. At various times the breather has been poorly fitted to the cross pipe, but without detriment to the running.
Funnily enough, I've never had mine come out of the metal cam / rocker cover, as yours was.
I've not checked for fluid in the pipe to the MAP sensor, so can't compare with your findings there.
I haven't checked the IAT sensor in the way you describe, and forgot today. The air temperatures shown in Rovacom have
been believable.
There is no positive MAP at tickover, so all in all I'm surprised, but pleasantly surprised, that what you have done has
affected an improvement to tickover. I don't even have a theory!
Ah Ha. "1999 P 38 manual transmission". I've just checked. As yours is a '99 it probably has the plastic manifold and
EGR. (Plastic manifold good, EGR bad, IMHO). Therefore 'anything' that upsets the EGR is to be blamed for all ills!!
I don't regard removing the inlet manifold as 'trivial'. Having just done it again to day I have confirmed my previous
experience.
Some tips.
Having new gaskets to hand is perhaps obvious, but it may be worthwhile finding if someone does them cheaper than the LR
Dealer. Part number STC 2203 (6 off). As a BMW engine it may be that motor factors have them from alternative suppliers.
It appears that the later engines, with EGR and a black plastic inlet manifold, use the same gaskets. The manifolds are
not interchangeable, as the stud positioning is reversed on 3 inlet tracts, in a mirror image style, on the heads used
with the plastic manifolds.
I strongly recommend you lay in a stock of manifold nuts, packs of 5, STC2199. These are 'special,' as they are not only
flanged, but for the stud size they should be 13mm AF, but are in fact 12 mm AF. This aids access. It is very easy to
drop at least one of the lower ones, and they have a habit of sticking somewhere invisible and inaccessible, rather than
falling through to the floor.
I now use a large plastic floor tray when working in the engine bay, so I can hear when things land, but even so I
dropped one nut, and lost it, perhaps behind the starter motor.
A slender built 3/8" drive socket set comes in handy.
With the manifold off it will be a lot easier to change the fuel return pipes. I thought I'd do mine 'while I was
there', and right swine's they were. The rubber had gone hard and weak. It was easy to break them, and trying to spin
them on the spigots merely twisted the pipe off. Fortunately the spigots are steel, so withstand the necessary knife and
'small straight screwdriver as a chisel' approach to removing the remains. I greased some with Petroleum Jelly, and
lubricated others with diesel fuel. Something is required to get them to slide on fully.
It is essential to remove the manifold to change the heater plugs, which was my task for today. I find I don't need to
remove the HP fuel pipes, but use an assortment of sockets, UJs, and extensions to get in everywhere. Most
significantly, for the plugs I use a 12 mm 1/2" drive socket, to give me the internal depth to accommodate the stud, but
then use an adapter to facilitate using the 3/8" UJ, extension etc.
Note that new BERU plugs, from LR at least, do not have new nuts, so you definitely don't want to drop those.
"I will take off the inlet manifold and check the crankcase sensors below it and any stepper motor that might be on the
injector pump."
Hmmm.
Certainly taking off the inlet manifold reveals lots of bits that aren't normally visible, never mind accessible.
A power box may connect into the round plug and socket you will find, so discovering how that unscrews will be useful.
The only sensors are in the cylinder head, the front one supplying the temperature gauge, the rear one supplying the
engine ECU (with coolant temperature). I have changed the rear one with the manifold in place, but it took a 19mm (3/4")
lightweight box spanner, strategically cut as short as possible while still clearing the terminal socket, then blanking
the end and brazing in an old 1/4" drive socket so I could use a 1/4" drive extension. This was the only way to clear
the HP fuel pipes, although I did have to loosen the adjacent pipe clamp to give a bit of flexibility.
There is no stepper motor.
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Gruß
Carsten ;-) | |
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