So I have an Lt1 in '69, the way i've had it setup is the following connections have always gotten power on key.


c100 a pink injector #9
c100 d orange power feed from pcm fuse 8 to pcm
c100 g pink power feed from ignition fuse 11
c100 k pink power feed from ignition fuse 10
c105 b pink power feed from injector fuse 10
c230 g pink power feed from pcm ignition fuse 5

It was brought to my attention that they should be receiving constant power.

Now I'm thinking the ones that should be receiving constant power,

are

c100 a pink power feed from injector #9
c100 d orange power feed from pcm fuse 8 to pcm
c100 k pink power feed from injector fuse 10
c105 b pink power feed from injector fuse 10
c230 g pink power feed from pcm ignition fuse 5

and the one that should be reciving Key'd power (ie to turn the pcm on and off) are

c100 g pink power feed from ignition fuse 11


is this correct?

Thanks
-Brahm

 

Brahm.. here is what I have from the 1994 F-Body GM service manual...None have constant power from Batt
C100-A from fuse 9 to injectors 2,3,5,8 hot in Run, Bulb Test or Start
C100-D Traction Control Active from ETCBM (Elect Brake TC Module) A16 to PCM C11
C100-G Ign fuse 11 Hot in Run, Start, Bulb test to Coil and ICM
C100-K from fuse 10 to injectors 1,4,6,7 hot in Run, Bulb Test or Start
C105-B Cant find a 105 connector C100-B is AC relay pick from PCM B6 to AC relay B5
C230-G From fuse 5 Hot in Run, Start, Bulb test to PCM pins D3 & B30 and MAS pin C

 

Thank you for your response, so does this mean there is no power going to the PCM when the car is off? Does it write all it's adjustments to a solid state drive? (ie fuel adjustments and what not), or is there an alternative wire I am missing that should be keeping some sort of constant power to the PCM to keep things in memory, so I don't reset the pcm every time I turn the car off?

 

ok I think i may have found my missing wire, I'll find out tonight.. 210 Orange, should be receiving constant battery power. So all these stay the same. Is there anyway to test and make sure it's saving it's memory (something I can see via a datamaster?)

Thanks
-B

 

nevermind my harness is a '95, no orange wire going to 210, not really sure where the power to the PCM goes now..

 

ok, I figured it out.. it is the c100 d orange for a '95, that wire doesn't exist on the 94 harness.

 

...

 

what a mess, the motor is a 93 that got swapped to a newer pcm so I don't have to burn eproms, the harness is a 95, and I believe the OPTI is a 94...madness.


Almost got the re-wire done. I just need to Relay the meizer water pump, put some inline fuses for the PCM, Water Pump, hook up the lights to auto meters clean it up all up and secure it behind the dash, and if I have time find where the heck the body harness wire went for my fuel tank sending unit.. I swear I had that thing hooked up at one point nothing like going on a 7-8 hour drive threw the desert with a 10gallon fuel cell, and no fuel gauge..hmm.. should I pass this gas station or just double check to be sure... hahaha

On the list after that, striping all unused connectors and plugs I can't wait to clean up the engine bay.

Oh, and Rob thanks again for your site, If it wasn't for you I never would have got this thing running! I swear I went cross eyed staring at those diagrams and what not. Next time painless wiring kit!

 

Alright, update on my progress. Really went to town rewiring the car this past week. After all was said and done i'm getting 13.5v in the PCM w/out lights, but when I turn on my headlights It drops to around 12.5, after a bit more investigation it looks like I'm loosing a FULL volt from the alternator, to the battery, and another half volt or so from the cut off switch back up to the engine bay.. Now that my PCM wiring is all squared away (I think). I need to re-wire my remote starter solinode and battery.

Regardless car drove pretty darn good, took her about 1000 miles and got in 4 passes @ Barona 1/8th Drag Strip with a best of 8.29 @ 82.3mph w/a 1.8 60ft. While nothing amazing, not shabby for a motor that is setup for power adders with none, and not having a tune.

So with that said. I logged my runs. If any of you care to take a peak, and give me your feedback, or thoughts on where to improve. I would be grateful.

http://www.brahmgoodis.com/xfer/logsbrahmbarona.zip


Many of the errors cleared out once fixing the wiring, but I did get an odd 02 error.. I fixed this by finally sealing off my evac system, I think but didn't clear the codes until the drive home. On the 400 mile drive back I had nothing but the lamp, error and one other non-important one.

 

First time I've seen a data log more than 1.5 hours in length. Were you shutting the engine down at all? Every so often it drops out of closed loop, but that happens after the engine run time resets to "0". Or does it just lose power to the PCM at times?

You have 6 codes, including one for failure of both O2 sensors. The others, CCP, VSS, MIL, and brake switch stuck on are probably relate to the install. There are a lot of "data errors" indicated. That can happen when there is electrical interference with the data wire or you logging cable.

You are getting huge knock retard spikes (12 - 14-deg), but some of those are tied into the data error flag. When its cranking for restart, the system voltage drops as low as 7V. TPS voltage at closed throttle is 0.84V, a bit on the high side. Might want to check the throttle blades to make sure they are closing all the way, or slot the sensor so it can be rotated to bring the voltage down toward 0.65V.

In PE mod (~WOT) the O2 sensors are indicating over 1,000mV, indicating a very rich mixture. Yet there are other cases where its in open loop, and running on Cell 18, and the O2's in PE mode are in the mid 300 mV's. Too lean.

MAP at idle seems to be in the 50-60kPa range. What cam are you running?

Probably more, but that's all I had time to look at.

 

First thank you for your response. I wanted to get all my runs in one log (still using the trial.. unless I figure out how to really use the features of datamaster I'm not 100% sure I want to buy it. So I was stopping the log, and starting it for each of the runs. Some of the passes have more time between them as my water pump, and fan don't go threw the PCM so I was leaving the car running, with a bit of gas in the staging lanes to keep her heated and powered up, I also wanted to watch to see if she was going into CL ect. Which is one of the reasons for the run time, and the open/closed loop. I'm stating to think the second reason is because my fan ect are all setup independent of the computer, I think the car is cooling down to much when not under load, which is knocking it out of closed loop is that possible? I believe there was a min temp you had to be at before the car would go into closed loop no?


The 02 sensor one was a wierd one, I got that within the first hour of my drive from mammoth to san diego, I was driving down from 9000ft to about 2000ft, in construction zone and had to coast.. at some point the car started acting weird, I gave it a little gas it cleared up and I ended up with that error... (it didn't do that again the rest of the trip..)

The VSS issue is gone now that I was able to fix the volts from what it was before, once I cleared the computer it didn't come back.

The CCP is still there and the Lamp, but I was thinking about disabliing those in my tunercat file.

The break switch stuck is a new one.. No clue whats going on there, maybe it grounded on something?! I don't have it hooked up.

The data errors are what have me worried, I never had that issue before a few weeks ago and now it's pretty constant. It seems to be a bit better since I improved the volts in the pcm, but I have no clue what is going on or how to fix it. At this point in time, I'm nervous about uploading a new tuner cat file as I don't want it to drop connection during the upload and from what I understand...ruin the PCM?.. Is this possible, and correct? What's the best way to resolve this?


What should I do about the knock spikes? I have HUGE headers from my old blower motor 1 7/8th and I'm not sure if I have a stock, or lt4 sensor will that help. The cranking issue, I hope to resolve once I re-wire my remote starter how I have it worked great with my old motor but not with the current higher demand of power from this EFi setup. TPS voltage, I've been fidding with this, I had it lower..but it went to low I just upp'd it before I got to the track so I wouldn't die on the line hahah..I'll drop it down to 0.65v

How do I fix this, better yet where do I start, I've been searching and trying to read what I can but haven't' found a good.. "put down your jets, and pick up a lap top..how to tune lt1 efi guide online", anything to point me in the correct direction would be great. I just have no idea where to start, what's a good mv ect ect.


Thanks again for your time I appreciate it at, unfortunately I do not know what the cam is it came with the long block when I acquired it. I was told a "mild blower cam"

-Brahm

 

Pulled down the current PCM tune, and did the following.
On the Switch table, I Removed error 11, 26, 37, 38
On the Constant table, I Changed the Cylinder Volume to 727.17 (it's a 355), fuel cutoff 1st gear up to 6650, 2nd-6th to 6657 (it was bouncing off the rev @ 5700-5800), and the appropriate fuel return.

With that said I don't know what else to do really, I've been looking at the BLMs, ect.. I read this.. http://www.lt1howto.com/articles/pcmtuning.htm, and it seems like if I really want to learn to tune the car I need a wide band 02? is that correct, or is there a lot I can do with what I have first?

As far as knock what should I do? Try an lt4 sensor?

Thanks again,
Oh, and if you guys check out that log file, I know it's big but if you just look at the last "hump" that is the 8.29 pass, so the best it performed.

 

Not answering any of your questions, but just nice to see someone else with a 69 and LT1/4L60E combo.

 

Thanks, and likewise. How did your swap go? How's your engine bay turnout.. mine is a CLUSTER of wiring haha.. I'd love to see some photos of somebody who managed to clean it all up. I was going to get some vette covers but my fuel lines are altered for AN lines and they won't fit with a bit of chopping.

 

http://s70.photobucket.com/albums/i1...t=000_0307.jpg

Not as clean as I would like. I would probably do the wiring a little different next time.

Brian