Boost gauge install .. looking for some tips
 

In trying to get my mind off a week of unpleasantry (family wedding, yikes), I'm ordering and planning to install a VDO boost guage in the 124. I've chosen the ashtray as my location and I'm going to T into the pressure line going to the ALDA. My questions are:
-What's the simplest way to run the tubing through the firewall and out of the ashtray opening where the back of the gauge will be?
-What's the procedure for hooking up the lighting? Don't have much experience with wiring, but I'm assuming it's fairly straightforward.
-I'm ordering from Egauges ... do I need to order anything other than the gauge (30PSI Vision Chrome)? I have the tubing and T connection.

there are usually plugs in the firewall for vacuum lines with one or two open.. or the holes where the AC lines run into..

I did not hook up my light wiring but what you probably need to do is wire it into something that is on when the headlights are on so it is illuminated.. I dont know the 124 chasis so I cant really tell you

I put mine above the left speaker on my 124- I never had a really good spot to put it, but wanted it closer to line of sight than the ashtray.
anyways I did same as above and ran the tube through where the rest of the wiring came through. remove the lower dash panel and trans tunnel panel on the left side and that should give you the access needed to install your stuff, i'll try and get pics

here ya go. gauge line is yellow, leftover from a parts car :D

Get the 0-15 psi gauge. 0-30 won't show enough movement.

I wired mine right into the fuse block. If you want the gauge to light when the ignition is on, pick a fuse with a constant. If you want them to light only when the lights are on, wire it into the headlight fuse.

Be careful drilling holes in the ashtray area -- in the 124 cars, the sensor for the airbag is behind the ashtray!

You may need an adapter to fit the vacuum hose onto the gauge but that should be available from your local hardware store.

Tee into the line before the safety switch, not before. Lots of existing rubber ports through the firewall. A 15 psi gauge is plenty, 30 psi is too high, as was said. Mine rarely gets above 10 psi.

Seems to me that the lighter is illuminated so you could steal the wire from its lamp to illuminate the gauge.

Thanks guys. My gauge was shipped today (I went with the 15PSI as advised) and I'll update once I get it and dig in.

So do you have to drill holes to get the tubing into the ashtray area, then? I can see now how to get it past the firewall, but can't see how to get it into the console and out the ashbin.

I'm doing the same, and I wish I would have gotten the 0-30 gage.


mine tops out the 0-15. It's better to have a gage that reads more than what you need (or thought you needed)




Stock t3 spikes to (an estimated) 18psi. I think it's a boost leak/wastegate problem. I'd hate to see what the temps are on the exaust side (and yes, a rebuild is planned - It's getting a bigger turbo, intercooler, external wastegate and propane injection)


and it's already the fastest 300d i've seen

Then I guess you've been hanging out on the wrong side of the state LOL!!

instead of driiling.If you dont smoke.remove ashtray.Go to specialty wood shop and buy piece of rosewood that is same size approx.refinish with a boat varnish(very durable and shiny).drill hole for gauge and lighter socket(assuming you have a car charger for phone).Install gauge and socket.run vac line from intake port thru firewall above steering and thru console to back of newly made gauge mount.attach and use screws from ashtray to install(pre-existing holes)
Worked out quite well for me.sorry no camera for pics and no cell either,but I put socket in anyway for passengers that do have them.

The 1987 W124 is a different car, unfortunately, making an ashtray install possible but harder to do than your 1984 and my 1985 W123 models. The ash tray is shallower in the 124 and behind it is the sensor for the airbag so space is definitely at a premium.

I would have never thought a Diesel turbo would put out over 15 psi in its stock form. Learn something new every day.

If you need phone assistance, you always know where to find it! :D

Check those manauls I know you have to find where the factory illumination wire is.......

it'll goto 20 before blowing, i'm sure.


Not to sure about the 3k though...