Steve Wong chip install question

[Hugh R]

I installed my stock chip backwards when swapping out my S Wong chip and it seemed to erase it. Yeah the notch thing is what you want to look for, not the orientation of the type on the top of the chip. Fortunately a friend who sold his 911 had a spare stock chip for smog testing. He gave me his stock chip for a ROW 84 911 for free. What is the chance of having a friend (from PP) one mile from me with the exact same car and a free chip? Gotta love it.

[Porsche 911]

Originally Posted by ischmitz

the screw on the AFM is for the idle mixture. If you tighten the screw you won't allow air to bypass the flapper and as a result all air needs to pass through the flapper. This will make the idle mixture very rich. The basic setting is to have it three to four turn loosened.

The throttle body has the stop adjustment that sets the opening of the throttle plate at idle. That in combination with the ICV decides how much air is introduced into the engine and this defines the idle speed.

ingo

Ahh - the saga continues i guess.

Now about 75% of the time the engine idles at the correct ~850 rpms, but a new problem just arose - perhaps (hopefully) directly related to your post above. Now the engine stalls when i clutch in and add gas in the middle of a shift (think rev-matching or "blipping"). When i clutch in and add gas when parked, the rpms go up, then go WAY down (maybe 200 rpms or lower), before stabilizing at ~850 rpm.

Do these symptoms sound like a direct result of overtightening the idle adjustment screw, thereby making the idle mixture too rich, or is the DME/electrical circuit the culprit?

[JJ 911SC]

Originally Posted by Porsche 911

Ahh - the saga continues i guess...
Do these symptoms sound like a direct result of overtightening the idle adjustment screw, thereby making the idle mixture too rich, or is the DME/electrical circuit the culprit?

Mechanical...

[ischmitz]

Yes. If the mixture is way off the idle will surge.

[kidrock]

Bullett,

gently tighten (counter-clockwise) your air/fuel mixture screw with a 3mm allen wrench until it stops turning (don't overtighten!!). Then, watching the rotation of your allen wrench, back the screw off in a clockwise motion for a full 3-4 turns. This should give you a rough ballpark estimate of the correct mixture for your AFM.

The correct fuel to air mixture is 14:3 if I remember correctly. This can be measured by a competent mechanic with a piece of equipment called (I think) an LM3.

[Porsche 911]

Originally Posted by kidrock

Bullett,

gently tighten (counter-clockwise) your air/fuel mixture screw with a 3mm allen wrench until it stops turning (don't overtighten!!). Then, watching the rotation of your allen wrench, back the screw off in a clockwise motion for a full 3-4 turns. This should give you a rough ballpark estimate of the correct mixture for your AFM.

The correct fuel to air mixture is 14:3 if I remember correctly. This can be measured by a competent mechanic with a piece of equipment called (I think) an LM3.

I did precisely that (using a 7mm socket) and the engine doesn't stall anymore when i add gas while clutch in - problem solved (unfortunately the yellow cap fell apart when i took it off, hope PP or someone local has that part).

Now back to the previous issue of engine idling at 1200 rpms. Now I need to screw on the throttle body clockwise 1-3 turns.. is the throttle body represented in the picture below?

[nkotselas]

does anyone know of a steve wong or other good chip for euro spec models? I can only find steve wong chips for us markets

[DRACO A5OG]

Contact Steve, he can set you up.

[DRACO A5OG]

Porsche 911,

You need a LM1 or LM2 to obtain proper A/F mixture.

Then properly adjust idle (7MM adjustment screw) to 880RPMs when properly warmed and jumpered as referenced in the Bentley Manual. Remember the the tach starts at 200RPMS so you want the needle just above the middle of the 1000RPM mark and 800RPM mark.

In a pinch, you can use a DVM and your O2S to obtain a rough A/F mixture.

What I am trying to understand is before you installed the 911Chip. Did the OEM chip run normally? It should have been a simple plug and play.

Has the AFM been tampered with, evidence is a removed cap from underneath.

[kidrock]

OK, lots of crossed wires here.

Bullett, I was referring to the 3mm screw on the AFM (air/fuel meter) that adjusts the air to fuel mixture. The AFM is the metal box that is directly connected to the big plastic airbox.

The 7mm bolt with the yellow cap is the idle adjustment screw on the throttle body.

You won't be able to see the darn 3mm screw. Hopefully, somebody has a picture.

Like DracoA50G says, the SW chip should be a plug & play affair. But getting you hooked up right shouldn't be a big deal.

[dnovick911]

Hey guys - Turns out I need to install a jumper on the "mother board" for the SW chip install on my '85 3.2. I lost the tiny wire given to me with the SW chip order. What do I use to replace the little wire to connect B703 and B704?? Thanks! Dave

[geoz]

looks like all you need is a short piece of wire (any wire really) to solder in place.

[dnovick911]

Thanks HG. I grabbed some narrow gauge copper wire.
BTW - "Jumper" soldering on my '85 targa is no easy feat.
I'm mechanical enough to work on my old dirt bikes a lot, and I practice soldered a bit on my work bench, but that is NOT an easy job and the space is very small to work in.
I'm gonna find someone local and skilled with the soldering gun to finish this up...

[JJ 911SC]

Originally Posted by dnovick911

… I'm gonna find someone local and skilled with the soldering gun to finish this up...

You (or he) will need a 70 watt iron with a very fine tip using fresh 63/37 rosin core solder, available at you local electronic supply store ~ $4 (tube size).

[dnovick911]

Originally Posted by JJ 911SC

You (or he) will need a 70 watt iron with a very fine tip using fresh 63/37 rosin core solder, available at you local electronic supply store ~ $4 (tube size).

That helps! thanks very much. d

[dienstuhr]

You can solder the jumper in yourself, it's not too hard. I did mine and it was the first time I'd ever soldered anything - I had to go buy a gun and solder to do it!

I found it easiest to work from the back of the board - basically to put the jumper wire in place then put a blob of solder to hold it there from behind.

I discovered this after the jumper apparently came loose after I reinstalled the board in the car... but the second time was the charm.

Cheers

d.