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firemedicsafd

firemedicsafd

Professional Murphy magnet
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I have an 88' k5 blazer with a 79' motor, 82 700r4 all sensored up to run correctly on an 88' harness and computer. The problem is...it does not! It will start fine, run ok but not great...it feels like it starves for fuel at high rpm, and drives ok. I have a TV cable issue i need to adjust cause i HAD the TBI spacer, had the tranny rebuilt, then removed it cause i was told it will destroy the trans. It does not idle after it warms up. it runs off idle ok but when it gets to a stop it will slow down, lope the idle till it goes down far enough to kill the motor. I tried to fix that by following the instructions on here for changing the idle with no luck. Since i do not know what the computer came out of, i think i need to reprogram the computer. i have another computer but it does relatively the same thing. I want to get the info on here for you folks to see, but i cant get it off my actron cp9185 scanner to this site. I want to get those fancy EFI live or Moates tuner programs. I also read on here about a wide band O2 sensor that fixes or allows for better tuning of the truck for more power/ mileage. Do i need them? how can i diagnose what is wrong with my blazer without spending the waste of time taking it to a shop? I have a laptop and i can get...if i need to... the cable to hook up to my truck and buy or download whatever i need to help me fix this thing...but i NEED guidance! Thank you!
 
Here are the numbers off both ECMs can anyone tell me which is the better match for my truck?

One has 1227747 AMUR
86AMUR K381301037

The other has 1227747 ASDU
86 ASDU K301642404


Thank you!
 
last 4 digits 7747 vary comon comp for our trucks.

problem is behind the 2 little screws and plate there is a chip for each motor combo.

chances are you might have the wrong size chip like 305 for a 350 .

and the 79 motor have a tbi cam or reg old style pattern cam ?

tbi stuff like diffrent specs for cams and still run good. if you know the specs on the motor in it now you can get a chip burn for better performance. data logging would be best for full custom chip burn.

www.tbichips.com has lots of good info to read and get chips.
 
Yeah but both those ECMs should run a small block chevy anything fine. They are the same ECM, just differant chips. I did not look them up but they both sound so familar I think they are both 5.7L. So again they should both run.

For the trans I would have to look them up and make sure they are for 700R4.

Question: What is done to your motor? What TBI injectors? Sounds like a long project, how old is the fuel?

Typical answer to what you have already said is "Sounds like a Vacuum leak. What is the fuel pressure?"

You have a scanner so I am assuming no codes or we would be looking at that.

You said "feels like starving for fuel high RPM" Could be but don't worry about that now because a lot of 5.7L feel that way around 3500 to 4000 RPM and it's getting to much knock sensor feedback and ECM is backing off timing. Unless it is not pumping enough fuel.

If you have a laptop and can get a cable the program you need is called WinALDL and it'll give a good idea what's going on. But your scan tool should too! I have an AutoXray and now that I have learned everything from WinALDL from reading the internet I can use the scan tool just as well.

Don't worry about a wide band O2 sensor right now. What I think you were really asking about is a heated O2 sensor for idle issues. They are completly differant animals. But right now not a concern...
 
Eagle, is there a site or place i can look up what the numbers exactly mean? When i get winALDL and get a file for data logging, how and where do i get a custom chip burned at?
 
This should answer your chip broadcast code question.
http://www.diy-efi.org/gmecm/ecm_info/1227747/

Once you get iot figured out I can burn you a final chip.

Data logging will tell a lot. Once you get your laptop, WinALDL and a cable I will walk you through the datalogging and then we can all look at it here to analize before a chip burn.
 
AWESOME! im waiting for the laptop to get out of the shop ( imagine that!) and the cable to get here. then ill do some logging and send ya the info. THX!
 
OK....got the laptop, aldl cable, and inverter for my blazer. The cable came with a bunch of programs to record the info. Eagle...which one do you want the info from? I have tuner pro, efi live, winaldl, and im sure whatever you want is on the disc and i can copy it to the laptop and record it in whatever format you want. Just let me know! Then let me know how you want it recorded.....cold running...hot running...catch when the problem happens. Thaks a bunch!
 
Ok Eagle- i FINALLY got the cable laptop program and now the blazer communicates with the computer. I even got the computer to read the raw data. I also logged some data. What do you want now? Is there any special situations where you want me to log the data? Like @ cold idle, WOT, Highway crusing, or any specific gear?
 
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