924Board.org

[kaffine]

Well I finally got my 931 up and running. I had to take a day off school to get it done on time though. I'll be getting it registered tomorrow and hope to get the plate EOVERIR (Ohm's law) I'm deffinatly a geek. I finally found out why I had an intermetent surge/hesitation the fuel pump grounds through the boost switch on the pipe from the turbo to the throttle body well that piece wasn't grounded correctly so whenever it shifted it would cause high resistance in the ground for the fuel pump. I have an oil leak I need to fix and more electrical problems than I want to think about there are wire nuts every where and the positive battery cable has a ground wire tap (normally found on comercail buildings) no insulation on it and it's fairly close to the fire wall and the battery isn't secured. So now I need to wait a few days to make sure the guy from the city sees that all my cars have been moved and registered and then I can put the 924 up on stands and get the timing belt replaced and then do the same to the 931 before I drive it anymore.

I'm trying to decide how I'm going to tune the 931. I know a shop in town that has a dyno and exhaust analyzer that I might take it to. I might get an 02 sensor gauge and tune it that way or there was something that screws into a spark plug hole to allow you to look at the flame to determine if it is rich or lean. I had to tweek the mixture to get it to pass smog I finally got it to pass with a 0.6%CO it was at 5% when I first tested it I had it up to 12% at one point unforutantly I couldn't adjust it with the exhaust analyzer hooked to it I had to drive around the back adjust then bring it around to be tested again because of the laws in this state thankfully the guy at the smog station knows me, I take all my cars to him and it wasn't busy so I was able to make several attempts.

I'm not looking forward to tomorrow I get to start out at the DMV then get a few things done around the house then go to school and hope they have an open lab so I can get the lab I missed done.
_________________
80 924
80 931

The best desciption of an atom boils down to something unknown is doing we don't know what.
Sir Arthur Eddington

[jpab924]

Well, let me tell you something...You don`t need a gas analyzer to tune in your mixture. Buy a cheap dwell meter, and a timing light. If the o2 is healthy, you can set the fuel system`s dwell. Pretty easily done. The mixture will be close if not dead on..... That is, if there are no vacuum leaks and the fuel delivery system is in good working shape.

Take a close look behind the left (driver`s) side strut tower. See a 3 pin round connector? IIRC the color wires are bl, grn, yel....You ground the black wire at the connector without touching the other 2 pins. I recommend using a jumper wire from the connector, to your alligator clip on the dwell meter. Ground the other lead of the dwell meter to a nut on the strut mount. Make sure the meter is set to 4cy dwell.

Now set your mixture when the bouncing needle is around a 45 dwell angle. It will jump around. This just means the 02 sensor is working and sending a signal to the freq. valve to adjust the mixture. :You will hear your freq. valve buzz back and forth.

A higher dwell number (50+) means leaner, a lower dwell number (40 -) means richer...

Use this method, guaranteed success...it works for me anyways!

Post your 931 threads over in the 931 discussion. They tend to stick around a little longer before they fall out of sight....

[IXLOR8]

Can you use a dwell meter to set the air / fuel mixture with a dwell meter?
_________________
Wisconsin

[D Hook]

jpab924: At the risk of sounding like an idiot, could you explain that hook up to the dwell meter one more time? What gets grounded to what? I have a dwell meter and sure like to try this.
_________________
'80 924 n/a SOLD

[Gram]

Isn't he referring to a 931 with an O2 setup..?
_________________
'82 924 NA Euro (hers)
'98 Audi A4 TDI (ours)