All right, sometimes my car runs badly and I may have narrowed my problems and I need help to know if it has sense.

The car is a 1986 240DL N/A B230f with (I guess) LH2.2

Onto the ignition module under the hood there is a vacuum line connecting to a vacuum sensor of some kind. While the engine was running I unplugged it and felt very, very low vacuum if I compare to ANY other vacuum line in my car... Can it cause a problem if so what would it be and mostly do i need to run a new vacuum hose?

Second the throttle position switch, I hear it click when I gently turn the throttle body so I guess the injection cpu knows when NOT to idle but I don't hear it clicking when going for WOT; should I and can it be broken?

Third, when I open the oil cap on top of valve cover what kind of odor should I expect? I mean mine smells a little like gas and I am not sure wether it is normal or not... What can it be and mostly how do I fix that?

And just for info; what purpose does the vacuum line on the fuel pressure regulator serves?

Thank you all on this site for making my car run over and over!!

>>Onto the ignition module under the hood there is a vacuum line connecting to a vacuum sensor of some kind. While the engine was running I unplugged it and felt very, very low vacuum if I compare to ANY other vacuum line in my car...<<

It could be ported vacuum, which is almost nothing at idle, but increases as the throttle opens. Try it while revving the engine a little, and see if the vacuum increases, then reduces back to nothing when you close the throttle.

Sometimes the vacuum advance on the distributor is operated by ported vacuum, not manifold vacuum.

The vacuum for the ignition control module on his '86 B230F (Jetronic 2.2) is not ported. It's a long vacuum line (stiff plastic to eliminate expansion/contraction delays) that runs directly to the intake manifold, right next to where the two other vacuum lines attach that go to the Flame Trap and the Interior Climate Control. (in close proximity to fuel injectors #2 and #3) If you've got a vacuum leak on this line, it will throw off your ignition advance a little bit, and also lean the mixture too.

If I recall correctly, on my '87 (basically identical to your '86), I do not hear a click when the Throttle Position Sensor reaches WOT (Wide Open Throttle). However, the switch does close electrically so it does function properly but without making a sound. (the idle switch side of the TPS does make a very distinctive click as you have noticed)

If you have a very distinctive smell of gas, check your Fuel Pressure Regulator. If you have fuel in the vaccum line coming out the front nipple, then the internal diaphram is ruptured and the FPR must be replaced immediately.

If you loosen your oil cap, but leave it sitting on the valve cover, it should stay down while the engine is idling. If it jumps up, gurgles, or spits oil out the side, your crankcase pressure is too high. Remove and clean the Flame Trap and associated PCV plumbing, -and I would strongly recommend removing and cleaning the oil breather box (just below the flame trap) since it is probably clogged as well.

God bless,
Fitz Fitzgerald.
--
'87 Blue 240 Wagon, 247k miles.

To minimize vacuum problems, about every 50k miles it's a good idea to pull the intake manifold, disassemble & clean the throttle body, clean all the vacuum orifices, check all the vacuum hoses for hard loose fitting or cracked ends, check and adjust the throttle body switch, replace the o-ring on the end of the throttle adjustment screw, replace the flame trap assembly, clean or replace the breather box located below the flame trap on the block, replace the hose from the flame trap to the intake, and check wire ends for bad (rotting) insulation. Along with the intake manifold gasket, order a throttle body gasket kit and breather box and idle screw o-rings. jp

Onto the ignition module under the hood there is a vacuum line connecting to a vacuum sensor of some kind. While the engine was running I unplugged it and felt very, very low vacuum if I compare to ANY other vacuum line in my car... Can it cause a problem if so what would it be and mostly do i need to run a new vacuum hose?

If there was a leak in that vacuum line it would cause poor running. If I'm not mistaken that line runs from the ignition module under the crank pulley and then all the way back up to the throttle body. Can't hurt to run a new hose, but before you do that look into other causes. If you are still primarily using your original vacuum lines, you should replace the whole system. I think IPD sells a kit, and the actual sizes and lengths that you will need are listed in the 700-900 FAQ. You can't just get the standard sizes they sell at Kragen. Volvo vacuum lines are slightly different.

Second the throttle position switch, I hear it click when I gently turn the throttle body so I guess the injection cpu knows when NOT to idle but I don't hear it clicking when going for WOT; should I and can it be broken?

What do you mean by WOT? If the TPS were broken or misadjusted (sounds like it's working OK, it just has to click when the throttle opens, and then click again when you close the throttle - but you can't always hear the click when it closes), that would cause some poor running in that your RPMs would race sort of randomly, since your computer didn't know it was supposed to be idling.

Third, when I open the oil cap on top of valve cover what kind of odor should I expect? I mean mine smells a little like gas and I am not sure wether it is normal or not... What can it be and mostly how do I fix that?

It should smell like an engine, which is a sort-of burnt oily smell, but not really too much like gas, though I gas a really slight gas odor might be normal. If you smell a lot of gas you're probably running very rich. There are a number of reasons why that could be.

And just for info; what purpose does the vacuum line on the fuel pressure regulator serves?

The regulator does its job by helping to create more fuel pressure when the car needs it by using the intake vacuum. So yes, if that vacuum line is leaking it would car poor running. And if you detect the presence of gas in your FPR vacuum line, that would indicate a ruptured diaphragm in the FPR that would cause a very rich, flooded condition.

But you don't mention what you mean by "poor running." Do you mean low power, rough running, rough idling, or what? Be more specific and we can be more helpful. Also, it would help to know what you've done recently to address the problem. When did you do your last full tuneup with sparks plugs/wires, dist. points/condensor, filters, etc.? When have you last cleaned your throttle body?

If the vacuum line on the front of the fuel pressure regulator smells of gas, that is the poor running problem probably.