Setting up my TBI

[1great40]

Hello all and thanks for having such a great forum.

I have a 4.3 Chevy V6 in my 40 Ford pickup. I installed the engine using a Painless performance TBI wiring harness and so far I have not had much success making it run correctly. I am running the specified computer and as of tonight it's running the Painless specified PROM and Cal-pack (almost) I ordered the correct PROM and Cal-pack from AC/Delco The computer is the 1227747 the PROM is a 16139566 and the Cal-pack is supposed to be a 16060836 and that's the number on the AC/Delco packaging but the number on the chip itself is 16060837A Since the engine is still not running correctly ( dribbly injector spray and it seems quite rich) can anyone tell me if the difference in the numbers on the Cal-pack could be an issue or is it something more on the order of an updated piece?

I have a Holley 12-927 fuel pump and have modified the internal fuel pressure regulator to make it adjustable and it's set for 11 PSI with a new 0-30 PSI gauge. I have had the same results as far as the fuel spray with 2 different sets of injectors. The injectors are the Yellow/Blue color code and the throttle body is P/N 17089018, both of which are supposed to be correct for this engine. Although I had never seen the engine run before I bought it it' supposed to be stock and I have verified that it is an '89 block. I was told it came from an 89 S-10.

The initial timing was set according to the Painless manual and although the engine won't idle smoothly, I've attempted to set the idle speed according to the Painless manual as well. The latest thing I have checked is the correlation of the CTS resistance using a conversion chart found online against my dashboard gauge and they are within 10 degrees of each other. The reference voltage for the CTS is 5.0 volts at the connector with the connector unplugged and key on. I have tried to back probe the CTS connector and measure the reference voltage with the connector installed and the key on but cannot get a voltage reading. Not sure if this is a real problem or pilot error. I know I've thrown out a lot of information but I'm hoping that someone can shed some light as to what needs to be looked at next. Thank you!

[EagleMark]

What is the four letter BCC code on the chip?

Really need to scan for error codes first, then get a data log to look for issues.

IIRC Painless instructions still have pin B10 Park Neutral wire grounded? This makes ECM think it's always in Park Neutral. When not grounded it is in Drive... this also gives IAC full control of idle.

[1great40]

This PROM doesn't have a 4 letter code like the one I took out. Instead it says 1613 where the old PROM said AKMH. The check engine light is not on and all I have is a basic OBD1 code reader and it's not showing any codes. I checked the park/neutral switch and it's wired to provide the ground signal to the ECM when the truck is in park but the reading at the switch is 11 ohms, not really hard ground. The ground path for that signal is the wire going back to the ECM which the Painless manual says is grounded through the ECM.. Does this help at all?

[EagleMark]

Can't find a match for those chip numbers as scan id? So I don't know what it is, would have to read it...

Ground in Park and Open in Drive is good.

You should really get at least an error code for EGR if it is driven, won't happen at idle.

Can't do much else without a data log to look for issues?

[1great40]

I usually do all of my own work but there is a guy I regard as really good at a local garage and he seems to know his stuff when it comes to electronics. I will talk to him about the data log and get back to you. Thanks so much!

[EagleMark]

A scantool and good tech should be able to spot an issue.

Seems you have the basics covered. One thing that is killer on these systems is a vacuum leak!