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Stuck in koko still

B

blumpkin

idi expert
Messages
64
Reaction score
125
Location
Ontario
This all started when i tried to do the koko procedure.
So far i deduced that the fsm did not have a resistor in it,..so i put a #5 in.
The symptoms are very hard smoky start very retarded timing, dead pedal until it gets a little heat in the engine (1-2 mins) after its gets a little warm it idles ok and drives a little sluggish but ok (ish)
As soonas it hits 170 it foes into relearn but will not accomplish the whole procedure,. it seems " stuck in relearn, running rough, extra smoke,. i can hear it varying its timing and as it gets slower idle to a point where it kicks in some timing and fuel and the rpm jumps to 8-900, smooths abit, the repeats the cycle ad infinitum.
Other than try and find another ecm, is there someway to clear or erase this ecm's memory?
It is a non egr engine.
If i throttle it up to full rpm for a few seconds it seems return to idle and run fine until after a few seconds it will return to rough idle and then repeat the rpm bumps to keep itself running,.
some other idea's would be welcome,.
 
If it was stuck in learn mode then you should be able to bump it out by unplugging the CTS sensor because the computer then would think the coolant temp is no longer above 170*F. This is a quick way to test your hypothesis.

It should throw a TDCO out of range code if the pump needed moved. In that case, get the injection pump back to as close as vertical, bump it 1/16" toward driver side, lock it down and see if it'll learn in range this time.

Also, check for other codes because your symptoms are indicative of other things also. Like a sticking or worn fuel solenoid/armature with closure time codes.

We tell everyone it's not a bad idea to run the process if you didn't personally set the timing correctly on it before because there's a very high chance the job was not completed properly on the last injection pump replacement the truck had before you got it. But, it can be troublesome to get it right when you aren't experienced with it. In the end, the truck will be better off, however.
 
Thankyou to everybody that replied,.. truck is a 99,.. i have a code reader it cannot perform any sort of test,.
I will have a look at the stepper motor,. and the connections to the crank sensor,. i will warm it up again and then see if disconnecting the ect sensor makes any difference,. it doesn't make any difference on a cold start,. and i will try the ohm tests that i can see in the chart,. i do have another pump i can install,.

and yes koko was initiated 'just for the heck of it" so we would have an example ,..
 
if you have or can get a bluetooth code reader, the ELM327 Denata mentioned will work. you can get the app called Torque on an android tablet or phone. you'll need the paid "pro" version. there are some "pid" files that will need to be loaded on the app. I have a copy of them I can send you or you can find the files and instructions on Quadstar's site linked below. set this all up and you can do just about everything from reading live data to iirc performing the koko setting the timing.

quadstartuning.com

6.5L EFI Diagnostic Scanning for DIY Owners

At Quadstar Tuning, we always use the phrase "We can't have fun with trucks that don't run properly!". In a world of electronic fuel injection (EFI), the 6.5L platform was revolutionary in the diesel sector. It was the first US EFI diesel engine that was available in the light duty truck...
quadstartuning.com quadstartuning.com
 
dbrannon79 said:
if you have or can get a bluetooth code reader, the ELM327 Denata mentioned will work. you can get the app called Torque on an android tablet or phone. you'll need the paid "pro" version. there are some "pid" files that will need to be loaded on the app. I have a copy of them I can send you or you can find the files and instructions on Quadstar's site linked below. set this all up and you can do just about everything from reading live data to iirc performing the koko setting the timing.

quadstartuning.com

6.5L EFI Diagnostic Scanning for DIY Owners

At Quadstar Tuning, we always use the phrase "We can't have fun with trucks that don't run properly!". In a world of electronic fuel injection (EFI), the 6.5L platform was revolutionary in the diesel sector. It was the first US EFI diesel engine that was available in the light duty truck...
quadstartuning.com quadstartuning.com
Click to expand...

This is the proper way to determine if a KOKO is needed.
 
I really appreciate everybodys suggestions,. my code reader is an old plug in with a cable,. very rudimentary. i have an iphone, i have very poor android skills.
Thankyou denata for your diagrams and troubleshooting charts,.
DJ i am not well versed enough yet to use any files to help with this but thanks for the offer.

The suburban is just sitting at the moment,.it troubles me as i have had a 6.5 diesel for a daily driver for about 20 years. I modify them to my liking drive them hard sometimes and enjoy their clatter as you all do too i'd guess, but i fail when it comes to repairing the ecm controlled side of things. i prefer an obd1 setup just for the ability to command lockup when i want it.
once you park something and have another daily driver or two motivation to fix diminishes. Not to mention the high cost of fuel,..
Thanks again for all the new info,..
 
spent some time today,.
Cold start is same problem, only its fixing itself quicker,. It fires, runs fairly slowly, quietly, and with lots of smoke,. then suddenly BAM the timing comes in and all sound good no smoke healthy sounding 6.5,..this may take 5 secs or up to a minute to get the timing to come in,.throttle pedal is dead till timing kicks in

as soon as the temp gets to 171 it starts missing coughing etc, trying to do its learn still,
I unplugged the cranks sensor and it immediately stops spluttering and runs with plenty of timing.
plugged it back in,. will not initiate koko unless codes are cleared.
cleared codes temp gets to 171,. this time i unplugged the optic sensor,. motor coughed ran rough then was searching for idle rpm,. (sounded like a blown alcohol motor) once it settled down it ran but with very little to no advance timing just ran steady but not a 6.5 chuckle,.

I pulled the ecm out to look at it,. somebody has been there before me,.small brown plug B11 dark blu wire has been cut and another wire added,.
bigger brown plug D10 grey w blk stripe has also been cut and a wire added,.both wires go thru the firewall somewhere,.to somewhere :droid:
I have been searching for a pin out chart so i can see what these two wires do (go to) can anybody point me to a ecm pinout chart for 1999?
The ecm is definitely 'stuck" in KOKO,. nobody seems to know how to make it stop doing it,.
my option is to let it enter KOKO and then pull crank sensor,. which will set a code and CEL,. and i think then it should now not try to relearn because it has a code,.? or i wonder if i shut the key off and then re-start if its just going to do same thing,. my ocd will definitely not like a CEL on,.. motor runs great,. getting a little blow by, probably due to not having changed oil in a while,.

I miss my obd1 truck,. i had a lock up switch for trans,. the 5068 pump, and one of toms custom flashed chips,. was all good,.
 
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