yohon

Hmm so is boost more the limit then load for cruise timing? I've been pretty scared to go past 30% load with cruise timing. But my running load is much more then yours. I typically don't see 5 psi until closer to 35- 40%

I dropped from 265 down to 245 75 r 16s highway tires. glad I followed your frecommendations on that as well picked up a mpg and truck feels alot better off the line. Rear diff is 3.55 i believe. I forget the final drive number for the 47 re but I did target the range you specified in one of your discussions

Absolutely. And thats pretty much where I'm at. I know my tune is not as good as yours and i know me being an automatic is not helpful (my in park idle engine load is higher then your steady state highway engine load) My commute to work is only about 20 min thats just enough to show the oil/coolant difference on the drive in. I know it's probably a little one the retarded side for the in town driving. And like you suggested my fuel table is well under stock levels until I get deeper in the boost table. Egts are well under control for towing and what not (turbo is probably a little one the big side to tow perfectly) but I just want more out of it. The science of it all amazes me and I have a laundry list of things to try water methanol the ram air a intercooler bypass propane injection ect. I currently run a consistent 21 mpg per tank (hand calc ) on the drive to and from work. If I run to Dallas or Austin I generally get closer to 24. Towing 75hp skid steer on a trailer from Austin I got 14.

I might disagree with you on that. Your absolutely correct tuning will have the biggest effect on efficiency power egts ect. But i think anything i can do to help that turbo work less shurely can't hurt. I guess we will know after some testing

New thermostat is in the truck! Well sitting in the bag in the passenger seat. Was going to install that and try and simulate a hood scoop with a leaf blower to see the effect on egts and see if this is even feasible before I go cutting and welding. I figure i could run a high idle program on the quad and compare reading with ambient air and then blow a leaf blower at the turbo inlet and see if it makes any significant changes. I don't expect any changes in pressure to the inlet but maybe air velocity will have its own benefits. More to follow this weekend!

I've been meaning to swap thermostats to a 200 degree but how do you keep the quad reading temp? Anything over 200 and mine gets funny. Gage cluster still works but all my alarms are based on the quad readings. I have probably read every post you and me78569 have written what yall have gotten these old trucks to do is nothing short of crazy.

I'm guessing by retarding timing your wanting to spool the turbo more? At highway speeds my turbo really isn't pushing anything I float between 1 and 2 psi at 65mph. When I drop out of cruise timing I don't see any change in boost until I get onto it. 30+% engine load. Im hoping to be more efficient not necessary get more power. Wouldn't retarding the timing cost me cylinder pressure/energy for the ignition event?

Absolutely! The thought isn't to make more boost rather to "force feed" the turbo a bit and make it work a bit easier hopefully increasing flow. If I can feed it .5 psi more at the inlet and drive pressureand everything else stays the same i should see more at the outlet for "free" I'm not shure if it will help when it's cold outside these diesel seem to like their inlet air pretty warm. I'd like to make a intercooler bypass for that reason but that's a lot more fab then I have time for right now.

Anyone ever do a ram air intake on our trucks? Bhaf seemed to be a good help and a good friend swore by the ram air intake on his VMAX bike. I feel like it would help in our application (diesel no real air fuel ratio no throttle blade) but I know it's mostly a looks thing on regular gas cars. Just curious if anyone has ever messed with it.

Glad it's working!

Mine is curved but it ends up in the same place if that makes sense. How far off is your linkage? You might be able to "adjust" it by closing the 90 degree bends on the ends here is a better picture of that curved linkage

Can you see what it needs? Park on the selector and park on the lever? Might be able to cut and shorten and re weld the existing rod. (Not to sound like the exact person moparman was describing)

You might try poping that linkage off (block the wheels!) And see if the transmission "tab"goes through all of the gears like it should or if the linkage is bound up. That will tell you if the transmission tab is clocked wrong or if your linkage is wrong.

I believe when you drop the valve body that shift linkage has to be undone. It might have been reinstalled incorrectly. This mine in park

I had the same problem on a 2001 I had for a short time OD would drop out randomly. It had a ton of problems. (Full of water) but the OD issue wound up being the APPS. I swapped the unit from my 2000 daily into into it and it drove perfectly.

I'll see if I can get a picture of mine during lunch.

Sorry for the late reply father had some surgery and I became a father truck got put on the back burner for a bit. But all of the wiring has been gone through and fixed ECM has been rebuilt and replaced truck runs and drives great thank you everyone!

Well good news bad news. Map sensor is fixed and finally wired correctly! Thank you tractorman! Bad news is I think the ecm is toast. Voltage across every sensor is fluctuating and crashing out. I checked the common power and grounds at ecm and it was solid. But thank you everyone for you help!

That helps so much thank you!

It does have an aftermarket lift pump on it and uses a relay. Good idea on checking that. Tractorman I know your an 02 not an 01 but any way you can tell me what order your map sensor wires go? Should be an orange Grey red and blue black wire.

Well I still haven't figured out the MAP sensor wiring yet. But got the scan tool to read a few more variables and it shows ECM battery voltage tanking whenever the truck cuts out. So I'm guessing this is showing either a bad ecu ground or bad 12v supply?

Does any one know how to tell what pin is what on the map sensor? I have the diagram but can't tell what each pin is on the plug. The truck is reading 28 psi of boost at idle so I think the 5v circuit is wired to the wrong pin shorting the circuit. Did finally get the truck to start the neutral safety switch is wired to a switch up under the dash. Something else to add to the fix list.

Finally got a chance to crack into this thing. Wiring looks like a mess (never buy a vehicle at night ) I'm guessing rodents got into it at some point map sensor pig tail is new but connected with wire nuts lift pump wiring had 3 butt splices in it ground wire was hooked on the alternator just a real mess. Thank yall for the help

Great thank you I'll post what I can find!

Starting this thread to help troubleshoot and document a host of problems with my father's "new" truck a 2001 24v 3500 dually with a 6 speed. Problems Truck will start and idle fine but will surge/buck inconsistently with throttle/load Codes p 1475 p0522 p0122 p 1295 p 0237 p 1488 and the companion code. Alternator ac noise seamed good <.03 No wait to start light but truck has a grid heater delete block on it not shure if it was installed "correctly" Probably is ecu but I'm going to check out the 5v system just to check. I did notice temp sensor was spliced thinking wires might be swapped? Grounding out the circuit Truck seamed to behave better when warmed up. Questions! Does the wait to start light still light up momentarily without grid heaters? Also lift pump cycled for a shorter time then my truck does (2000 vs 2001) both pumps are aftermarket airdog pumps. Can ecus be repaired/rebuilt? Any new ones on the market? Are ecus truck specific? I can't swap a 2000 auto with a 2001 manual? Thank yall for reading!