Carb to TBI conversion

[Six_Shooter]

I have now changed my ECM to a 1227747. I was told that the 16197424, which I now have, was OBD2 as it has red and blue connectors and I want OBD1. Was also told the the 1227747 does not have electronic transmission control capabilities, which I don't need anyway as I have a Muncie SM465. Does anybody have any experience with this combination? Also, do I need a VSS with this combination?

Did you mean 16197427?

That would be an OBD1 PCM and would be what I would use over the 7747. It has MUCH faster coms for better datalogging, more tuneability, and just a better overall ECM IMO.

[Dan Brown]

Using a 1227747 ECM to install a TBI on my 1974 Chevy K10. While studying the ECM wiring schematic I see pin C9 with a purple wire coming from the starter solenoid called "crank signal input". Is this to let the ECM know that the engine is cranking and is it needed?

[1project2many]

The crank signal should be connected. I connected it to the S terminal of the starter.

[Dan Brown]

My schematic also shows the purple wire going thru a 3 amp fuse. Is this correct?

[dave w]

My schematic also shows the purple wire going thru a 3 amp fuse. Is this correct?

Yes

dave w

[Dan Brown]

Thx Dave.

[Six_Shooter]

It's not absolutely necessary. I've used the '7747 with and without that connection and haven't experienced any difference in starting.

I mean, it's not a difficult connection to make so add it, but all I'm saying is, if you didn't, you're not likely going to experience issues starting.

[Dan Brown]

I've already installed it.

[clarkent5477]

I've already installed it.

How is it going? I just converted my 66 Cadillac 429 to TBI injection using a 1227747 PCM. I'm going to use the 2000 PPM Jag VSS, but wondering if the stock cruise+DRAC will work with that. That's down the road some; we'll see.

[Dan Brown]

I am putting a GM TBI unit in my 1974 K10 and am using the 1227747 ECM. I'm trying to make the check engine light come on and per the ECM schematic I need 12v switched to the bulb and a brown/white wire going to pin A5 which grounds out inside the EMC. I've checked everything I can think of, good bulb that works, 12v to the bulb, and the light won't come on. Does this mean the ECM is bad or could it be something else

[stew86MCSS396]

In response to your same question on TGO...double, triple, quadruple check your wiring. Idk what schematics you have that would have the A5 spliced to go to pin D on the ALDL... There's some schematics at the following link... http://www.gearhead-efi.com/Fuel-Inj...Information-42

[Dan Brown]

In the 1227747 schematics you sent me, the schematic on the top row far right is the schematic I have which shows the spliced brown/white wire going to pin D in the ALDL.

[dave w]

Found the attached .pdf on the web, looks correct to me.

[Dan Brown]

Okay, thx a lot, looks just like the way mine is currently wired. Now, since my check engine light won't come on, is there anything else that could be causing it to not come on besides a failure inside the ECM?

[stew86MCSS396]

In the 1227747 schematics you sent me, the schematic on the top row far right is the schematic I have which shows the spliced brown/white wire going to pin D in the ALDL.

Ahhhh...I didn't see that and ironically albeit not originally 1227747 but it would be plug and play, my '85 Caballero has a brown/wht wire going to ALDL D. I have no idea if it's spliced as you have said. I keyed on engine off and measured for volts and only got 0.1v. I verified that my ground was good checking volts on the cigarette lighter.

Edit: Wait a minute, the last schematic says it should read 0v with key on eng off but 14v with engine running.