Hi guy's.
Been working on the blazer still.Could not figure out the problems with the TBI on the vortec W engine so I went to the original CPI system.
I bought only AC Delco and Delphi parts.Had to make new fuel lines and change wiring harness.Couldn't get it to run.
Finally figured that we had to change the dash and interior harness,which contains the digital instrument cluster.I have mixed emotions about that too.
At least I can see the readings now.
When doing this you also have to change the throttle cable (which was lost) and kick down cable as well as the cruise control cable.
I wound up installing a throttle cable from a 99 Sonoma .Works but had to zip tie it to the bracket.
I have to say it does run a lot better but when cold idle seems to high and the transmission shifts long and harshly.My 91 and this one with the tbi cold shifted about 11-13 mph.With this cpi system,it goes up to about 21-25 .........BANG!!!!
Hot idle with cpi is @720 rpms.Tbi normal is 550 rpms.
I want that cpi idle down.
Any ideas?

 

- WHAT cable is free? Classic symptoms of transmission pressure modulator wrong.
Didnt I read somewhere the only PCM input to transmission in those models is the pressure solenoid?
Check your TPS.
EDIT: Apparently - according to your other thread- you have a TV {transmission valve} cable. Misadjusted, that will cause your shift problems.
Here's what I found on a search: {I'm not posting the site because it has a virus on it}
That equates how you adjust Ford AOD which I'm more familiar with.

If that doesnt seem to fix it all the way, do it again and just rotate the throttle till it stops full open. {sometimes pedal full down doesnt get there}

 

Your truck has a 700R4 transmission in it (well, maybe stated as a 4L60, but it's the same as the old 700R4). As such, you have a throttle valve cable which needs to be adjusted properly. There may be a difference in the brackets TBI to CPI that you'll need to investigate (depending on whether you have an upper plenum from a 92 model year or a 93-95 model year which came with the 4L60E transmission - hence no TV cable).

As far as the idle speed goes, cold idle at 720RPM doesn't sound too bad, but should drop to ~600RPM or so once warmed up. Is your IAC valve functioning properly?

Now, why don't you make a complete, comprehensive post in this thread detailing what your truck originally came with along with all of the changes you have done and why. You jump around quite a bit and it is very difficult to determine what you are working with as far as electronics and/or parts in some cases.

Also, lay off the sarcastic remarks about people waking up.

 

OK....WOW !
First off Man deepest apologizes if anyone took my backwoods since of humor the wrong way.I was basically implying that my posts were long and drawn out.Some may even say boring.Wasn't trying to tell you your feet stink.

As far as my project...yes I am probably jumping around a bit.I just assumed most of you have more experience than I and am probably boring you.
Although maybe I may be able to help someone out through my experiences(mostly failures) with the utmost honesty to avoid confusion.

The Blazer I have been working on for the last 2 years is a 88 s-10.It was drug off the side of a hill for parts for my 91.
In my garage sat a 92 4.3 vortec begging for my attention.
Again I never intended to do anything with it other than sell it or part it out.
I had heard terrible things about the CPFI system and everyone wanted the 88 fixed up...have no idea why.
My idea was to install a TBFI system on a W engine.The best of both worlds.Smooth running engine with a bullet proof fuel system ,like my 91.
So I rebuilt the engine and did just that.
Note:this was my first rebuild.
It ran great but would fall on it's face at 1600 rpm's.Here in WV that can be dangerous.
Remember everything from front to rear is NEW.PC and pump included.
After checking everything dozens of times I finally decided that the cam and heads were just to much for the TBFI system .
After careful consideration and hundreds of dollars later I installed the dreaded CPFI.I figured I have a 95 with the TBFI on it but it is very ill,so maybe just use those parts on it after I removed them (TBFI).
Now when installing a CPFI system in an older s-10 you have to start at the rear.You gotta change the fuel pump and sending unit.Got Delphi stuff from Rock Auto along with all the other parts including AC Delco fuel injectors and gaskets.
You have to make NEW fuel lines and change the wiring harness under the hood.Best to do that after removing the manifold and distributor.
Thank GOD my wife and daughter have small hands and enjoy working on the on vehicles.
While under the hood you have to change the throttle cable,kick down cable and cruise control cable because the TBFI cables are about 4 inches to short.This is where some confusion has been about the cable.
Someone misplaced my throttle cable from the 92 CPFI.
The only thing I had was one from a 99 sonoma.
It works but the end that goes into the throttle bracket is different and must be secured some how.I just zip ties.
At this time I still have not changed the kick down cable on the transmission due to the fact I have trouble working over my head.
Heck took me 2 days just hooking up the Y pipe.
So the only cable hooked up is the throttle cable.
I also replaced most of the sensors on the engine.
While having the trouble listed above with high idle (720 when engine about 200 degrees)I aquired a code 23...IAT sensor.Also checked the TPS to find a reading of 0.42 while throttle closed-4.84 wide open.Went ahead and replaced it while at it.It runs better but still having the shifting and high idle bang problems.
Ok back to the install.We had to install the original 92 Digital dash and wiring harness to get it to run (during the install).We could have used the older dash but would have been a lot more trouble plus other were staring at the digital cluster like a deer getting ready to jump in front of you.
Once all was installed we had to run the newer fuel pump wires back to rear and splice them.(purple and grey) older ones are (red and grey.)

There is probably a lot more that I have not included but am willing to answer any questions if possible.

What I need help with is ...the cold shifting bang and clang.Seems to me it should not be affected by the kick down cable be unhooked.Correct?
Also why is it idling high.I have checked the time,plugged the vacuum, and disconnected the throttle cable.I also checked it for gasket leaks.
The transmission shifted and worked great before installing the CPFI unit.
Could it be the PC chip?
Any help would be appreciated.
Again.....if I insulted anyone I didn't mean to.
Hope you enjoyed my short book.