Simon's take on: 'Mess Under the Intake'

[AustinK425]

So over all to pull this off properly its gonna cost $588?

[unevolved]

Where did you get that? I did mine for exactly $0 USD. I just used some hoses lying around.

[Simon S]

So over all to pull this off properly its gonna cost $588?

Oh, no - sorry if that total was confusing..

The last three items on the list there are preventative/"while you're in there" parts. A new ICV in particular isn't needed unless the old one is failing.

Air filter was included since it’s always a good idea and the intake system gets removed.

Fuel injector O-rings included since originals are now 20+ years old.

I suppose one can easily skip new hose clamps as well. The OE ones on my car were of good quality material and construction (quite re-usable). Like I’d sooner trust OE/original hose clamps over new “parts store” clamps any day.

Also note prices are from realOEM.com at list (dealer) prices as of whenever I made that post.
You’re going to get considerable savings going with a distributor such as blunntech (which I highly recommend).

[AustinK425]

Oh ok im still pretty green my m42 is in bad shape sorta...
Like to seem some how save it before it goes, ideally replicate your project but really starting with scratch and winter in the northwest isnt exactly an ideal time to start when you dont have a garage lol

[MattBimmer]

Thanks.
The bypass valve and associated bypass valve hoses are spliced into the stock heater core hoses.

To answer your question, new heater core hoses do not “eliminate the need”. The choice to install a bypass valve is up to you.

Per answers given in this thread, the bypass valve is a thermostat that closes off flow to the heater core in the event of elevated coolant temperatures. If you’re not worried about overheating your engine/coolant system, then I wouldn’t worry about installing the bypass.



If you get new heater core hoses, install them as is to eliminate bypass valve - or cut them in appropriate spots to incorporate bypass valve.

Fwiw, here's a RealOEM link to the "thermostat"/bypass valve parts and plumbing:
http://www.realoem.com/bmw/showparts...35&hg=64&fg=99

Simon ur write up is the only one giving me confidence to tackle this. In the photo the new and used comparison the new will come like that from say.... Blunttech. Then I plug it to the heater core and don't worry about bypass valve?

[Simon S]

Yes.

[MattBimmer]

Alright, I appreciate it! You'll probably be getting some PM when I start to dig into this thing.

[MattBimmer]

What hoses should I buy from blunt and which should be parts store hoses
Also any info on the wiring harness it scares me more than anything... Any notes of warning about it. I was hoping to tag each wire with tape and mark the spot where it came from. This is my first big wrenching project besides the Rack swap.

[Simon S]

What hoses should I buy from blunt and which should be parts store hoses?

The answer is in the first post of this thread provided as clearly as I was able to communicate – complete with part numbers, descriptions, pictures, diagrams, and everything.

Also any info on the wiring harness it scares me more than anything... Any notes of warning about it. I was hoping to tag each wire with tape and mark the spot where it came from. This is my first big wrenching project besides the Rack swap.

We all start somewhere – and you’re taking the initiative to do it so you’re showing the needed chest hair already. Tagging/labeling is a good idea. One mistake I made was to mix oil pressure and temp sensor connections at first. Another good idea is to take lots of reference pictures as you work. Most all things only go together in a certain way - so it's pretty foolproof. You’ll be fine.

And like I said – things start making sense as you take things apart. Did for me anyway.
Godspeed.

[MattBimmer]

Thanks a lot. And the first list of parts is great just trying to see if there are certain hoses that I need to buy from blunt, or ones not to worry about. Just worried I may buy a hose that won't be compatible when or needed when doing the modification. Thanks a lot and does anyone know how hard it is to disconnect the fuel rail from the wiring harness? Any good tips on cleaning the injectors/intake ports while its off? Mineral spirits right? Or would a carb cleaner work similarly. Sorry for all the questions, just the more I know the more confident ill be tearing into this.

[Simon S]

Just worried I may buy a hose that won't be compatible when or needed when doing the modification.

Matt, that list is as fucking comprehensive as I could fucking make it. e.g. intake gaskets are there because intake manifold gets removed – and you’ll need new gaskets. etc. I didn’t put anything on the list that didn’t need to be. To do the job and put it back together with worn/leaking parts/gaskets/hoses would a shame and a waste of time.

..does anyone know how hard it is to disconnect the fuel rail from the wiring harness?

Look at the connection plug – then unplug the connection plug.

One thing I did was have the engine running – then pull the #11 fuse. This cuts power to the fuel pump. The idea is that you’ll get the majority of fuel out of the system before disconnecting the lines. Note that you’ll still dump some fuel, but at least you’ve minimized it.

Any good tips on cleaning the injectors/intake ports while its off? Mineral spirits right? Or would a carb cleaner work similarly.

Yes. Carb cleaner on injectors. Brakeclean on intake ports. Not a whole lot of rocket science there. Whatever you’re comfortable with. Rinse them with WD40 if you like. When done, blow everything off with compressed air if available. Advise to install new injector o-rings and apply oil to them upon install.

You may want to replace the injectors.

Here’s the injector part number I ordered from Motor Man Fuel Injection Supply (www.injectors4u.com)
Bosch MPI injectors 0280150556
– from what I understand, they’re practically identical with exception of 4-pintle rather than our 2-pintles (as stated – for better fuel atomization).

Sorry for all the questions, just the more I know the more confident ill be tearing into this.

Again – you’ll be fine. Stop asking questions and just fucking go do it already. Google shit you’re curious about and come to your own conclusion – then go fucking do it.

Search. Research. Educate yourself - or go take your car to a fucking mechanic. The more you know the better off you'll be. Shit - I would barely trust myself if it wasn't for the hundreds of hours of research I've done. Even then, someone always has a different take on things.

and read this while you're at it..

[Simon S]

sorry.. didn't mean to be abrasive there.. I'm fuckin wacked out with anxiety lately..

Dude - you'll be fine.

[MattBimmer]

Ha I gotcha I know I am being annoying as shit and I realized that about the when I actually started order stuff. And your right the majority of ny questions are cause I am trying to peek at it around upper intake anyways. Parts are ordered and hopefully all goes well. Thanks for this write up and all the help though.

[MattBimmer]

Started tearing this stuff apart. Unfortunately it's a real mess inside. For the harness input on the alternator do I just yank it off or is there a special trick? I don't wanna screw up my harness disconnecting.

[Mr.SWISS]

I did this for a friend that just bought a 91 318 vert that would die as soon as you touched the gas and let off. Had to replace the 2 3 way hoses that wrap over the u shaped heater pipe and the hose that runs to ICV, hose to front of VC and small 1" hose to intake/tb.

charged him $100 parts and labor. He was stoked to drive it.