-80SC not running, what did I do to it
 

ok only have had it for a few months, always started right up, ran a little rough but was working on it, pulled into the garage and did these items and now it doesn't run:

1) new hood struts, pulled the gas filler to get at the pin and clip (wiring down there but don't think I did anything)
2) pulled the relay fuse to clear everything, of course put it back in and I can hear the fuel pump running
3) pulled air box cover, cleaned and replaced with two new straps
4) changed the oxygen sensor but the car side connector crumbled (have new one coming from Louie)
5) changed the deck lid struts
6) noticed when I was near fuse box two wires not connected, came from the Ungo Box in the glove box, one was the one side of a double wire they had, other was single wire, niether was stripped back and can't see on fuse panel where either could have went/broken off

-now it cranks but doesn't fire and I can clearly tell the fuel pump is on
-newer to Porsche 911's but nothing on any of my gauges move or light up when I put the key to the on position or crank, no tach, no fuel.... is this normal?

thanks in advance to the guys with knowledge and willingness to help a newbee

Wondering if the Ungo box might be the root cause

should add I have now completely disconnected the Ungo box, I did not find any wires going to a relay like most cars in seaches I found had

a) there was a single wire going to what I thought was speaker wire in the back package shelf, didn't pull the rear panel to see where it went but can't believe it is releated to my issue, it ran under the passenger carpet then back under the passenger seat

b) there was the wires as in picture below, I believe the yellow is radio, and it had a scotch lock going to a red wire with fuse that then went to the brown wire on the multi-connector

c) I believe the yellow/red is for power mirrors (my car doesn't have) and it was stripped but not connected to anything
http://forums.pelicanparts.com/uploa...1529881480.jpg

d) what is the multi connector?

http://forums.pelicanparts.com/uploa...1529882432.jpg

it is located to the left of the ashtray and has the spades facing downward

-the brown wire that connected thru the in-line fuse red wire that was stotch locked to the yellow wire

-now it cranks but doesn't fire and I can clearly tell the fuel pump is on
-newer to Porsche 911's but nothing on any of my gauges move or light up when I put the key to the on position or crank, no tach, no fuel.... is this normal?

All of your gauges should indicate when you turn the key to run. Do your wipers or turn signals or headlights work?

Also check to see that the three rubber body/pass through connectors are still tight. They are right behind the ignition switch behind/under the dash.

And the spade terminals are grounds.

great idea Marc, I didn't look back in there far enough

-will check when I get home from work today

Do you have a Bosch ignition box? Do you hear it with the key on?

yes standard Bosch box, I didn't listen to it, what kind of noise should I expect to hear with the key on?

There should be a high-pitched whine.

-ok will check that also when I get home

If it cranks then the first thing I would check is for is a spark at a plug. Remove no. 4 plug lead and attach spare plug (or remove plug and use that). Place plug on engine to get an earth, get someone to crank the engine while looking for a spark. If you get a good spark then suspect fuel. Not sparking also results in a smell of fuel at the exhaust
Let us know the result of the spark test

ok, no whine from CDI box, no spark when I crank, Marc's idea of 3 plugs under the dash by ignition switch looks like they are all plugged in well, do smell fuel when cranking

a) can't see well behind the master cylinder and booster so I pulled gauges, behind oil/fuel gauge I see a relay base with nothing plugged in but looks dusty like nothing was plugged in there and sure don't know how I could have done anything way up in there there

b) I still wonder why none of the instrumentation shows anything when I turn the key on

no turn signals, but wipers and headlights both work

I doubt many, if any, here knows the workings of that box. Suggest looking for the specs for the Ungo or backtrack and reinstall it to see if you can still start the car. You did take pictures, right ?

yes took pictures of everything, can't really tell what it was hooked to that even mattered, only thing of any significance was on the bottom of the fuel pump fuse

-it did die before I removed the Ungo box

ok, lets start at some basics... Turn key on and check both sides of all fuses and let us know what you find.. (they all should have power on both sides except the headlight hi and low beam fuses.. (4 of them) unless they are on.

Leave key on and check to see of you have power on the red wire going into the CDI box. (you can unplug it for easier access.

great idea Marc, will do tomorrow, I'm done for today

What were you trying to clear? Something to do with on board diagnostics (OBDII)? Hmmmm...

-sorry should have been more specific, pulled the relay to allow physical room to get the gas filler neck out and not hit anything physically

-what I wrote totally reads like I was trying to clear some fault/memory, sorry for the confusion

SC won't start
 

In the 14 wire connector (engine compartment on left side behind cover) there is a small gauge red wire that provides switched power to the Bosch CDI box. You can pull the small 6 wire plug off the bottom of the CDI and use a test light to see if it is indeed getting power with the ignition turned on. No power here, no startee! Another thing you can try is to remove the air filter cover and filter and try lifting the air plate slightly to see if you can hear the fuel pump, injectors squeal and the CDI noise. There are a couple of electrical things plugged in behind the CSI box that could have been knocked loose, check that. As mentioned earlier, doing a spark check with a spare spark plug is a good idea also. Whoever put in the "Ungo" box may have cut into the switched power wire that feeds the CDI. Take a close look at all the places where you cut out the Ungo wiring and see if you can find an interruption. Good luck!

Fred, 14 pin from engine harness only provides constant power direct from alternator.
CDI switched power is a direct run from front fuse panel that also goes to lower fuse of the rear 3 fuse panel for checking. Can also test for power at 2 terminal white “T” connector beside CDI box.

http://forums.pelicanparts.com/uploa...1530057984.jpg

here is chart of all voltages measured with key on

-also no voltage at red lead on my CDI box lead

Fuse position 11 & 12 (from front of car) has zero volts? Check your ignition switch. You have no switched power.

so to sum it up no voltage (not counting head lights as switch was off) at either side on:
#9 - Front right Flasher light
#10 - Front left flasher light
#11 - brake lights and others
#16 - Fuel Pump
#21 - Power windows

-all of these items used to work

strange reading is bottom of the fuse on #20 A/C blower fan reads 8.9V even though there is no wire feeding the top

-I really appreciate everyone's assistance and even though I'm new to 911 I am a long time car guy, I have searched tons of threads, they are all different and didn't find one to describe my issue; I have Bentley Manual but I really don't want to ring out the entire car (or worse bring it in someplace, been many years since I've been stumped enough to do that); I'm hoping my findings above will jog one of our experts thoughts and start me down the right path

ok going to check now

timmy2 and Marc are both Porsche geniuses!!!

-plug down by ignition switch is loose, moved the pins a little to make better contact, fired right up and looks like everything is working

-man I knew it would be something like that, I must have bumped it loose on my last drive, even though last night I checked that it was pushed in it was too loose, tight now, driving it to work tomorrow - yeah!!

thanks again to all, found a connector not plugged into anything back by CDI box, no idea what it is for, I will post a new thread with pictures, guess someone knows exactly what it is

WooHoo!

Good deal. :)

Uh huh, so the switched red wire going to the CDI was not getting power? I could say "I told you so", but will settle for congratulations on finding the fault. And, you should have learned a good bit about how these critters work! Good job!

Yes Fred you were also correct, thank you again and I think I only need 99.8% more Porsche knowledge and I will be semi functional with them

Is this the ground point G2 under the dash? I have been trying to find it and I found these same connections tonight. Doesn't look like a standard ground connection to me that's why I'm confused. If not, where is G2? Bentley says it's behind the heater controls, which is essentially where this photo is from.

yes that is behind the heater control and a little to the drivers side

I saw it there myself in my car today. Just wondering though, is this ground G2 from the Bentley Manual?