New TBI owner in need of some help....

**simadownow6988** · 02-23-2015

Hey guys,

I have an issue that I hope someone can point me in the right direction to fix.
I bought a 1989 K5 Blazer a few months ago. The owner had done alot of upgrade work to the Blazer and it was a great price for what it is. The previous owner had a GMPP motor dropped in 2 years ago. Its a 1996-2000 model Vortec crate motor with a GMPP intake manifold for TBI.
After driving it a few days, I noticed it was running a little rich and hesitating on idle. Upon research, I found Brian with TBIChips.com. He recommended that I replace my fuel pump with a higher volume one, get a 3 wire o2 sensor since I have long tube headers, run a custom chip, and get rid of my Holley tb for a custom 46mm (which he gave me the info to TBIparts.com).
After installing all the products, including the 46mm tbi with 18 lb spring and flow matched injectors, I cannot seem to get my idle down below 1200. The guy with TBIparts (that built my tbi) has been helpful with my issue, and he even had me send back the tbi for inspection (which came out fine). I have replaced the new TPS and IAC, but no change. No vacuum leaks either.
Brian with TBIChips is basicly telling me that he cannot help without a computer hooked up to it.
Any ideas? Any help will be much appreciated...

**Fast355** · 02-23-2015

Originally Posted by simadownow6988

Hey guys,

I have an issue that I hope someone can point me in the right direction to fix.
I bought a 1989 K5 Blazer a few months ago. The owner had done alot of upgrade work to the Blazer and it was a great price for what it is. The previous owner had a GMPP motor dropped in 2 years ago. Its a 1996-2000 model Vortec crate motor with a GMPP intake manifold for TBI.
After driving it a few days, I noticed it was running a little rich and hesitating on idle. Upon research, I found Brian with TBIChips.com. He recommended that I replace my fuel pump with a higher volume one, get a 3 wire o2 sensor since I have long tube headers, run a custom chip, and get rid of my Holley tb for a custom 46mm (which he gave me the info to TBIparts.com).
After installing all the products, including the 46mm tbi with 18 lb spring and flow matched injectors, I cannot seem to get my idle down below 1200. The guy with TBIparts (that built my tbi) has been helpful with my issue, and he even had me send back the tbi for inspection (which came out fine). I have replaced the new TPS and IAC, but no change. No vacuum leaks either.
Brian with TBIChips is basicly telling me that he cannot help without a computer hooked up to it.
Any ideas? Any help will be much appreciated...

Not sure why he wanted you to switch out the TBI other than the fact that most people connect the map sensor to the wrong port (the rear one) on the Holley TBI units and cause a rich idle and an off-idle hesitation.

**simadownow6988** · 02-23-2015

I really hate hearing that. He never mentioned that it could be as simple and cheap as moving a vacuum line (which mine was located on the back). That was 450 bucks wasted....

**Fast355** · 02-23-2015

Originally Posted by simadownow6988

I really hate hearing that. He never mentioned that it could be as simple and cheap as moving a vacuum line (which mine was located on the back). That was 450 bucks wasted....

Don't get me wrong, the factory style unit is better and the original design holley injectors are known to cause issues, but there is a known driveability issue when the MAP vacuum is attached to the rear port. Where the port is locate is right in the IAC passageway. As the IAC opens it causes a loss of vacuum signal to the MAP which cause the engine to run rich. When you open the throttle the MAP does not change much and the engine develops a lean bog from lack of MAP AE. The problem is noticeable enough that from my experience I can see it in a Datalog alone.

**simadownow6988** · 02-23-2015

Ok, gotcha. It is a little relief to me knowing that I now have a better tbi.
Any idea of what could be causing my issue. I ordered an ALDL cable off ebay from a Red Devil River. I also downloaded winaldl last night on my laptop. I will be reinstalling the tbi tonight and hooking a computer to the vehicle. Is there something I can do to post maybe a screen shot on here to help you guys help me?

**DanofMostTrades** · 02-24-2015

Sorry simadownow6988, I can't really help you much as I'm a newbie, but I just ordered that motor your running and am excited to see someone else with the same setup I want to run. I still have my stock throttle body and need to upgrade. If you want to sell that Holley, PM me a price. If not how was your experience with TBIparts.com? What all did you buy that added up to $450? I have also had a frustrating experience with Brian at TBIChips.com, but lucky for me I found this forum before buying anything more than the fuel pump. The guys hear have told me that winaldl is nearly obsolete and I should download TunerProRT, which I've done but can't play around with it til I get my motor. Have you bought a chip from Brian yet?

**simadownow6988** · 02-24-2015

I did buy a chip from him. He supposively made me a custom tune for my specific setup. I let him know everything about what I have.
Tbi parts has been awesome! I have the Holley still. I am considering selling it.

**DanofMostTrades** · 02-24-2015

This is the thread that led me to this sight, it may be useful to you as well. Go down to post #13 by Eagle-Mark. http://www.gearhead-efi.com/Fuel-Inj...ning-questions
If you don't mind, what part of AR are you from? I live in Searcy.

**Engine07** · 02-24-2015

Great to hear on tbiparts. I am about to buy new setup for mine as well and was looking at going with them.

**simadownow6988** · 02-24-2015

Well it looks like I have been screwed with this chip. Can anybody help me get a correct chip in this thing? I just want it to be right...

**Engine07** · 02-24-2015

Well, I'm new at all of this but I am slowly grasping some of it. One helpful thing, you said you ordered an aldl cable, is any of it in yet? Just from what I have seen I much prefer tunerpro rt as it is what I have and am familiar with. When you ordered your cable did you order any burning equipment? My first recommendation would be to download tunerpro as it it what most ppl here seem to run. Then get the proper mask files for your ECM to get some datalogs you can post to see what it is doing. The hard part if you don't have a burner/reader will be finding out what was set in the chip that is in there now. I see you are also in arkansas so if you need some help getting some of this figured out feel free to holler, maybe we can meet up sometime if you don't have the equipment I have the stuff to burn and read as well so we can get a copy of the file you are dealing with and get it on here for some guys to look at.

**Engine07** · 02-24-2015

Not sure where in arkansas you are from but I am from Bigelow and work in Conway

**simadownow6988** · 02-24-2015

Im in the Fort Smith area. About 2 hours away.
to be honest with you, I'm not even sure what mask files are. Im that new. Lol
I did buy a Aldl cable and will download the tuner pro software if it will help me get this motor running.
I do not have any burning stuff as I'm not planning on making a habit of adding stuff to my motor. I just want to get it running right now and leave it alone.
Any help you can give me will be MUCH appreciated.

**Engine07** · 02-24-2015

Yea that's a little haul, lol. If you can post the number off your ECM so everyone knows which one you have, you can look under the gm ECM bins and definition file link on here and find the files you will need to download to datalog under your ECM number. That will let us know which computer you have as well so we can use the right file to view your datalogs.