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# 6 resistor

R

Rodd

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When I swapped out my FSD a month ago (with # 5) I left the #6 that was in the replacement FSD. Is there anything I need to do or will the trucks computer recognize it indefinitely.
 
I thought that when you replace the resistor it will only start 50 times before something needs to be done.
 
Generally the ECM/PCM will stay happy as long as you dont make radical changes in the resistor.

The #5 will generally work in place of any resistor that may have been in the system before.

Bill Heath IIRC loves the #7

As long as there is one in there the little beast will likely not complain.

My DaHooooley has a #9 in the PMD and it seems quite happy.

The resistor is sort of a trim tab if you will to calibrate the pump to exact specs called for as far as fuel dilivery goes.

I think the #9 will allow 6% more fuel than say a #1.

Does not seem like much but every little bit helps.

MGW
 
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I think the OBD2s recognize it right away, and must have a resistor to work. OBD1s relearn it after 50 starts or when a TDC relearn is initiated and can run without a resistor at all.
 
OBD II is just a whole lot fussier for sure.

The more they overthink the plumbing the easier it is to stop up the drain. ??????????

MGW
 
buddy said:
I think the OBD2s recognize it right away, and must have a resistor to work. OBD1s relearn it after 50 starts or when a TDC relearn is initiated and can run without a resistor at all.
Click to expand...

The relearn is 50 start cycles or so for both. Otherwise, pull the battery cables for a minute or so.

Without a resistor, it will throw a code.
for non military application, #9 is the largest resistor number. Anything larger will throw a code.
Lower the number, the higher resistance (lowest voltage level returned to the PCM)

A good link on resistors can be found here, http://www.dieseltowingresource.com/showthread.php?t=12596


Regards,
 
Relearn on OBD-II will not take place until ko/ko relearn or scan tool relearn is initiated, it will run on old stored value until that happens, once it gets initated and PCM sees that no resistor is there PCM will set a resistor problem code, and will not start.

I ran with no resistor 3 mos to prove a point about "Steak-Boys" fuel controller & confirmed what we already knew, that his "on the fly" fuel adjustments via changing resistor values were just plain ole "bovine scatology" to quote one of my favorite generals.

OBD-Is don't recognize the change until 50 warm up cycles H2O above 170F, (not just starts), and OBD-IIs would never see it without a learn command. I "learned" mine after 3 mos. running resistorless and as soon as I did, I got a no start until I installed the resistor in the FSD
 
Turbine Doc said:
Relearn on OBD-II will not take place until ko/ko relearn or scan tool relearn is initiated, it will run on old stored value until that happens, once it gets initated and PCM sees that no resistor is there PCM will set a resistor problem code, and will not start.
Click to expand...

So what happens when you pull the battery cables? Will it relearn? (Teach me, I don't have a scanner)
 
Nothing happens to OBD-II with battery cable disconnected, another one of my experiments ran 6 mos with spare PCM in the back of my truck, with TDCO set for -1.5, I fully expected the PCM to go dumb and default to factory setting, it didn't even the stored fault codes I set stayed stored in the PCM.
 
IMHO, the thing will do fine with that small difference in resistor value.

If yours was a #1 and you installed a #9 then it might complain.

Now I had the battery cables unhooked on my 94 and 95 (OBD1) for 3-4 months, then refire after the builds and they dont seemto care much about things as long as stuff is where its supposed to be..

You should be fine, but if the 50 start cycles initiates a relearn and it does not like something It will let you know.


MGW
 
I think the stored items are not in volatile memory (Dependant on power to maintain)

Seems to me that it has to be deliberately removed or changed.

The codes in an OBD1 will go away when power is removed though.

MGW
 
jmiller said:
So what happens when you pull the battery cables? Will it relearn? (Teach me, I don't have a scanner)
Click to expand...

You have a resistor in the driver you have now correct ??? Assuming you do have resistor, warm engine to >170F, then shut down truck, put APP to floor, then with ignition key in run, not start; hold APP to floor for 1 minute, this will initiate the learn after 1 minute on then turn ingition off for 1 minute and APP in normal position, start truck and the new resistor code will be learned, also this will let the PCM learn the current TDCO setting.

If you don't have a resistor do not do the ko/ko learn procedure as you'll be down until you install a resistor, thought just occurred to me as I was typing this, I need to study on this more as to the requirement for the >170F for the resistor learn feature, as last time I played with this about 5 years ago I don't think the engine had to be warm to notice the missing resistor & replacement of said resistor.

But to initate a ko/ko for TDCO learning purposes you must be above 170F H20 with no stored codes in memory
 
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NP AKDD, it's not just boasting when we say this it THE BEST 6.5 site on the web, be sure to spread the word to your friends on other sites, you can get adequate advice elsewhere, or best advise here.
 
Have not seen the value in carcode or snap-on scanner so I don't think it will see it, if you will remember the resistor to be used is established when the IP is on a calibration test bench, so I think only way to know the exact resistor to be used is when on a test stand that is monitoring supplied current to fuel solenoid. IIRC Bill says best resistor for all purpose and what he supplies with his remote kits is a #7 resistor
 
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