Electrical gurus, I have a problem!

[delatlanta1281]

And it isn't related to my stereo. Here is what has been happening.
When I start my car it runs fine for a bit, then runs lean.
I have a volt gauge in my center console and what I am seeing is this:
When it runs full lean, the volt gauge is @ low 13s. While it is there my temp gauge is pegged in the red and the car is loping really badly and will not rev over 3k.
If I start and stop the engine (ignition) six or seven times while I am driving the car, the volt gauge will suddenly read 14volts, and the temp gauge will go flick back down to normal. My lamda sensor will start swinging normally and the engine will be strong. It usually runs fine until I turn it off and restart it again later. Then it may run fine, or it may run crappy. The thing is, I am CONVINCED it is an electrical issue. Here is what I have thrown at my car so far:
New Fuel Pump/ filters
Three 173 ecus
New alternator
New battery
New fuel and starting relays
New coolant temp sensor
Cleaned and serviced injectors
Cleaned the grounds for the coolant temp sensor
traced and re-wrapped the wires for the injectors and coolant temp sensors
Checked plugs, wires, distributor (although I doubt these were the issue)
Checke valve lash
New t-stat
Bled coolant system
New SI board batteries
Tonight the starter actually gave me some trouble. I turned my car off and tried to restart it, and it wouldn't turn. I popped the clutch, and started the car, and it ran badly (as stated before) all the way home.
When I got home, the car started fine (obviously the starter is on its way out).
What am I missing? I am going to check the wiring harness to see if it is loose tomorrow, but I cant believe it would be considering how intermittent this is. Could it be the starter? Why would the car run like crap with my voltage low and my temp gauge pegged? I know the car isn't overheating btw due to two things: I shot the t-stat housing with a temp gun, and when I turn the car off and then put the key to acc, the temp is normal. When I start the car it flicks up to red and pegs....
Here is what I am running.
M30 afm
19lb injectors
mark d chip 173 ecu
ireland plug wires
ireland afpr

WTF? Any insight?

[jeer]

have you done any checks on the ignition switch,
they usually give direct voltage/power to whichever compenant and if its really low everything will be out of wack, also try checking all your ground wires from the eng to chassy and the ones under the carpet from inside near the dme and cluster and so on.

happy hunting.

[george graves]

Yea, sounds like a possible ground.

Oh, and check the ground strap on the back of the head as well.

[E30 Cabrio]

Is it storing any error codes?

[delatlanta1281]

No codes, just a 10 second lean.
George, where is the ground located on the back of the head?

[george graves]

I think it's on the back of the head, passenger's side, right in between the head and firewall IIRC. It's been a while since I've wrenched on a m20 car. Since the head is not very well grounded to the block/rest of the car(all them gaskets), you want a ground strap there - that and I think it's for electrical corrosion as well - you know the dis-similar metal kind of corrosion.

[delatlanta1281]

thanks george!
I will check it out.

[delatlanta1281]

Bump,
I got some advice, here is what happened.
Ok
I pulled the yellow connector on the back of the cluster to no avail (the car actually wont charge with that off for some reason). I also pulled the temp gauge sensor (brown) and drove around for a while to no avail as well. It seems like it is happening during a voltage drop. For instance, last night it ran full lean all the way up the highway, then I parked it and it actually wouldn't turn over when I tried to restart it. I popped the clutch and it started fine, drove it home, turned it off, and it restarted just fine. I am noticing a voltage drop with my HIDs on and especially when I hit the brakes. Blinker as well. I replaced my alt with a new one, now I am wondering if the starter is drawing current.... Is this even possible?
BTW I can't find any ground on the back of the motor. The only ground to the motor I can see is the oil pan.
The battery line is ok. I am seriously thinking of replacing the entire wiring harness.
This is KILLING me.
I may actually have to bite the bullet and take this fucker into a mechanic!

[delatlanta1281]

Think I've got it!

I think we figured it out. The ground from the chassis to the top of the oil pan was loose and needed a good sanding. So far so good!

[mops]

is it still holding up ? i have similar issue.
it's better after i did engine rebuild but not quite there yet.
wierd thing is that when i do a cold start, i get a nice 14.0-14.2 V stable in the system.
After car is warmed up, even driving on the highway i get ~13.5V and if i stop and idle it goes low, and i mean ~12V and i've seen it as low as ~11.7V.
yes, the gauges on the dash seem to vary.
i suspect it's the grounding but i cant explain cold-warm phenomena i'm experiencing.

[delatlanta1281]

It hasn't hiccupped since actually.

[kronus]

There is a ground under the diagnostic connector on the intake manifold bracket.