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Discussion Starter #1 (Edited)
I finally got a chance to pull her into the garage and have a looksie under her dress :p I didn't have any particular agenda except to get to know her better. The air filter housing came off and I started to poke around. I removed the IAC unit to make sure that the two hoses are clean. It looks like one of them needs to be replaced and getting to it appears to be PITA.

I noticed that the air filter housing has a "shaped hose" from the valve cover. This hose has a tiny inlet and this inlet has been plugged using a screw.



I'm guessing this has been done for some time. Upon further investigation, I see a vac hose that appears to be going no where at the moment.





My guess is that this hose at one time used to go into the inlet of the shaped hose that goes from the valve cover to the air filter housing. This hose ends up going to this unit (see below), which I'm not sure what it is. Is this the diaphragm pressure regulator? I'd love to see a link to a electronic manual as I'm unable to find it. What exactly does this thing do?



Is my assumption correct in stating that this hose at one time used to go to the shaped hose?

I'm not sure if this is related to the code 16 (EGR) that is stored in the memory but it's worth a shot.

The throttle linkages is rather interesting to say the least! Tomorrow, I'll spray some degreaser in this area and start the cleaning process. I may find other things in the process.

If anyone has any inputs on the easiest method of replacing the vac hose that goes from the IAC to the base of the throttle body, that'd be great.

In the picture below, the right arrow is pointing to the hose I'm referring to.



cheers.
 

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That is the fuel pressure regulator and that vac hose is only if the diaphram ruptures saving gas from causing a fuel in your engine bay -- it is instead brought into the engine. Not good either way, but lesser of two evils.

Connect the vac cable to the screw filled hole.

Distributor's looking a little dirty thar!!! Get some carb cleaner or engine degreaser and get that bay a little clean, it'll be much easier finding gas leaks @ EHA, distributor and other locations.
 

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Discussion Starter #3
That is the fuel pressure regulator and that vac hose is only if the diaphram ruptures saving gas from causing a fuel in your engine bay -- it is instead brought into the engine. Not good either way, but lesser of two evils.

Connect the vac cable to the screw filled hole.

Distributor's looking a little dirty thar!!! Get some carb cleaner or engine degreaser and get that bay a little clean, it'll be much easier finding gas leaks @ EHA, distributor and other locations.
Excellent, thanks for pointing that out. I'll see if this vac hose will reach the screw fill hole. If not, I'll improvise as needed.

So, a Diaphragm pressure regulator is the same thing as a fuel pressure regulator. Good to know.

I agree, this engine bay is filthy, some spic and span is in order!

thanks.
 

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do put a baggy over that big shiny thing next to the distributor with the brass plate in it, thats the Air Flow Sensor, and you don't want to dump cleaner in there. A little volatile degreaser is OK if thats greasy itself, but cover it when you're cleaning the rest of the mess. Under the air flow sensor is the throttle body, you pretty much have to remove the whole fuel distributor assembly if you want to get intoo there, and frankly, don't, unless you really really have to.

I did, and this is what the throttle body looks like:



mine was quite filthy inside.


this is the bottom of the air flow sensor...


and the bottom of the fuel distributor that sits on top of it...


the air flow sensor pushes that pin on the center bottom of the fuel distributor up to spray more gas into the engine. the black electronic module on the side of the fuel distributor is the EHA or Electro Hydraulic Actuator, and its used by the Lambda control system to fine tune the fuel-air mixture.

mine all reassembled after surgery...


(I had to replace the air flow sensor as the potentiometer on the side of it was reading all wonky, and attempts to replace just the pot failed).

if you do take it apart, you'll probably need to replace this large rubber piece,


and you'll also need a new o-ring that goes under the fuel distributor. while you're in there, the idle air tubes will be much easier to replace (I didn't as mine were in good shape).
 

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ps, on that 'after' picture, I note that there's a little piece of black rubber hose connecting another piece of clear hose to the fuel pressure reguator vent line.... so you just need that to reach your crankcase vent tube off the valve cover...
 

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Discussion Starter #6
HOLY MOLY, that is one clean intake! Congrats. I don't have a huge desire to take this monster apart but would like to figure out a way to replace that tiny IACV hose under the intake. I'm guessing some busted knuckles is in my future.

Thanks again for the tips, much appreciated. The KE injection system seems overly complex to my uneducated eyes!
 

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HOLY MOLY, that is one clean intake! Congrats. I don't have a huge desire to take this monster apart but would like to figure out a way to replace that tiny IACV hose under the intake. I'm guessing some busted knuckles is in my future.

Thanks again for the tips, much appreciated. The KE injection system seems overly complex to my uneducated eyes!
well, that shiny clean one was a BRAND NEW ONE.

with hindsight, I probably could have fixed it cheaper, but I wanted to do it once and do it right. the air flow sensor assembly was about $450 by the time I was done (after core charges, and including the extra bits I needed).

next up for this car (a 1990 300E 2.6 that we were GIVEN because it had eaten too much money at mechanics without fixing the stalling and rough running) is to pull the injectors, and take them plus 6 more I have off another car being parted out, and find the best 6 of the batch... a local shop owner said he'd show me how to use the injector tester, coool! and I have the fuel distributor out of that other car and may well swap it in, or use its plumbing to make a fuel distributor pressure balance tester.
 

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Discussion Starter #8
I noticed lots of moisture under the PS res. Hopefully, after a good cleaning job, I'll be able to start sourcing leaks and hopefully repair them.

I placed my first order from autohauz: dizzy cap/rotor/O ring, Fuel pump relay, OVP relay, shape hose, coolant temp sensor and a fuel filter. Let the games begin I say.
 

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Discussion Starter #10

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Discussion Starter #12
Thanks for the pdf but my question wasn't about the IACV. It was if it was possible to remove the hose between it and the throttle body w/o removing the fuel distributor. :D
Oh, ok, I thought you were talking about the little hoses going to the idle control valve.
LOL, I was talking about the hose between the IACV and the throttle body. Is it possible to remove that short little hose w/o removing the fuel distributor up top? It seems to be buried nicely.
 

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Discussion Starter #14
Excellent, that's the info I needed. Thank you.
 

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Yea, he's pretty good at that taking time to document and writing it up kind of stuff. He keeps a good site too.
 

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Discussion Starter #16
idle air hoses

I'm not seeing these hoses on Autohaus's website. Can someone give me a clue as to how to find them?

TIA.
 

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Discussion Starter #19 (Edited)
Oh SNAP, thanks for the link. I feel like an idiot for not finding it :rolleyes:

Looks like I'll need the following:
1030941382 & 1030940482 (I'm not sure what is the "air slide" they're referring to!). I think these are two hoses that go to the IACV?

Might as well buy this one too! 1030940082

I already bought this one: 1030941082
 

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Discussion Starter #20
Spark plug gapping

So, I have six of the NGK BP6EF spark plugs and was curious if I should gap them to 0.8mm (per shop manual). They seem to be gapped at approx 0.70mm out of the box.

thanks.
 
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