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Could Use Some Help Setting TDCO on OBD I

OK I followed dBrannon79’s instructions. Basically allowed myself more time with plenty of daylight left to play with it, as opposed to trying to get it done with 30 minutes of daylight left. Ended up having to move it far to the passenger side as the driver’s direction just increased Actual from 9.0 to 11.0. Never saw 3.5 Actual, but more like 5.0. Codes stayed clear and went for TDCO learn and eventually got it at -1.94. It is no longer throwing codes and it runs nice.

1E38A5A3-45D9-4636-BC62-217382A6C753.jpeg8DDA1CB1-C2F8-42BD-B8F0-4A958C4CA0CB.jpeg

Drove it several miles. Runs nice and never threw a code.
 
Big T said:
OK I followed dBrannon79’s instructions. Basically allowed myself more time with plenty of daylight left to play with it, as opposed to trying to get it done with 30 minutes of daylight left. Ended up having to move it far to the passenger side as the driver’s direction just increased Actual from 9.0 to 11.0. Never saw 3.5 Actual, but more like 5.0. Codes stayed clear and went for TDCO learn and eventually got it at -1.94. It is no longer throwing codes and it runs nice.

View attachment 75745View attachment 75746

Drove it several miles. Runs nice and never threw a code.
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I dont remember what I read that some adjust the off set to. I know mine is set at close to -1.50 and it too runs real nice.
I do think that there must be a danger point where if it is set too high it might cause some piston damage.
Maybe someone can step in and clarify that information.
For some reason it seems that I remember less and less as time slips on by. 😖😵‍💫😹😹😹
 
-1.94 is about as far as you want, IIRC, I was there at one point but may be at -1.50 or -1.3# ? It's been awhile since I've had my trucks on a scanner.

That's a good thing.
 
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I have some new motormounts for my beast. After I get those installed then maybe I’ll take the timing around a bit more on this one too.
Last trip to Billings and back was yielding only about 15 MPG so see if a reset will bring that mileage back to the 18 or so range.
 
-1.94 was the lowest I could get it. So when it landed there, my shaking finger clicked on the off button for TDCO learn and I fell back in exhausted bliss. I’m going to accept this TDCO for now, because it is no longer throwing codes.

Drove it around three different times, not too far but all with coolant temp at 190+ and no codes. I will claim that as a victory for now, but will keep monitoring it. My one-armed wife and I head back up to Montana tomorrow. Marty’s IP will be along for the ride, to be shipped from Stevensville to Miles City. His IP has more shipping miles on it than actual run time miles.

I know my son gets frustrated with this truck and throws up his hands. It’s hard for me diagnose from Montana and then when I do get down here, my time and my son’s time are both limited, which is not conducive to troubleshooting 6.5 mysteries. Thoughtful patience and persistence prevails. Of course now with diesel at $6.50, it will not get driven as much. Rest assured, fuel prices will flip the other way. They always do. I am already seeing forecasts of $65 oil by the end of the year.
 
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Glad to hear you got it going. -1.94 I think is the max you want. like Will said it's for optimum performance. not sure how that effects the fuel mileage. I would think that the steel fuel lines may have been preventing you from turning it any further. mine would spring back in that sense due to the lines on the IP.
 
No, Les said that. I am just used to reading it for the last 20 years.
I never could tell any difference of 1° in a ds4, let alone part of a degree.
Kinda funny anyways because the difference of summer/winter blend is gonna swing that explosion 3°. If a feller wanted 1° of timing, 1/2 pint of gas in the tank does that.

Will’s opinion has always been and always will be set it at 2. As in db2.

As to anyone worried about fuel costs- again the mistake is made with a ds4 in the first place. Maybe if you live where there is only 1 mechanic shop it gets harder, but if you could get the used oils from a shop near you, 4 barrels, a few jerry cans and a centrifuge.
Poof your fuel cost just became few hours labor, and is now 27%(+-) the price of gasoline. The added ip life for the db2 and saved money on added lube is a bonus.

But wmo isn’t working in a ds4.
 
dbrannon79 said:
Glad to hear you got it going. -1.94 I think is the max you want. like Will said it's for optimum performance. not sure how that effects the fuel mileage. I would think that the steel fuel lines may have been preventing you from turning it any further. mine would spring back in that sense due to the lines on the IP.
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Yeah the steel fuel lines and their memory were impacting it, but I could get full motion range and did feel the hard stop to the passenger side when I tightened it down. This defied all previous TDCO efforts where it was always move it to the driver’s side. Probably explain why this effort required many attempts. I’m jusf happy that it’s there.
 
Moving it to a hard stop, makes me curious if the timing chain is off by one tooth or the sprocket on the IP off by one tooth on the timing set. might be worth looking at sometime. I'm sure Will or War Wagon will know more on this.
 
Good to know on the info of a half a degree and how much difference it makes.
Thank You Les.
When adjusting the timing. I have a large set of them waterpump pliers. Loosen the bolts, grasp that IP with them pliers, then rotate that IP and hold it while getting the easiest to get to bolt snugged enough to hold. Then snug the other two, fire the engine and once again do the timing relearn and see where it stands.
I am happy to be able to help out by having a spare pump that can be mailed around for folks to try out.
I have thought about selling it but then if the time ever come that I’d need a pump then 🤷‍♂️😹😹😹😹
 
dbrannon79 said:
Moving it to a hard stop, makes me curious if the timing chain is off by one tooth or the sprocket on the IP off by one tooth on the timing set. might be worth looking at sometime. I'm sure Will or War Wagon will know more on this.
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We just did this about a month ago when the key to the gear sheared off.64932E3D-A224-4BAD-BFB5-994FFEF797B2.jpeg
 
MrMarty51 said:
Good to know on the info of a half a degree and how much difference it makes.
Thank You Les.
When adjusting the timing. I have a large set of them waterpump pliers. Loosen the bolts, grasp that IP with them pliers, then rotate that IP and hold it while getting the easiest to get to bolt snugged enough to hold. Then snug the other two, fire the engine and once again do the timing relearn and see where it stands.
I am happy to be able to help out by having a spare pump that can be mailed around for folks to try out.
I have thought about selling it but then if the time ever come that I’d need a pump then 🤷‍♂️😹😹😹😹
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Ya, but when you do need it, it will be across the Country :)
 
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