Had the new TST on for a couple days. Today while driving with the remote on 3/3 under moderate/heavy acceleration uphill the engine missed one time very quickly. I was thinking this may be a sign that the stock lift pump is not keeping up with the engines demand now? I dont have a fuel pressure gauge yet. No codes thus far, and other that this one incident the engine runs really strong. Just wondering. I plan on doing Superduty's Walbro fuel system upgrade with the CP3 bypass. Thinking sooner than later now. What do you guys think? Thanks!

 

I have had my engine stumble under heavy load too. Im not sure why. I also have the r49 tst unit. It will happen some times under wot and will feel like the engine coughs or stalls for less than a second.

 

It could also be caused by the defueling feature of the TST. If your EGT's get too high, (depending on where you have it set), it will cause the truck to defuel, which will cause a stumble.

Jim

 

I have it set to defuel at 1200 deg.. I know this is low, but the stumble happened well below this point and at about 1/2 to 3/4 throttle. I drove it around just now and could not duplicate the condition nor set any codes. Hey MoparRiggan, how do you like your 62 turbo? If you don't mind could you pm me with the cost? I am going to replace the stocker and was looking at the 62, 64, and 66 from Industrial Injection. Thanks for the advice from all of you!

 

Did you lug it at 1200 rpm and it was cold out?

Any CEL and code?

 

It was probably close to 1200 rpm and temp outside in the 40's, so not real cold. No CEL, no codes.

 

If you do that three time in a short period of time...it will throw a harmless code...which will clear on its own in a short period of time.

The fix is simple...don't lug the truck or set the high idle @ 1200 rpms when warming up when it is cold out (< 50 degrees) or when the engine is cold. You will not experience that miss then. 1200 rpms is too low to lug the motor...hot or cold it is hard on it. It is one of the small quirks of an otherwise excellent fueling module.

 

Thank you very much cquestad! One more question if I may? In the instructions for the TST it states that 5/5 power level is ok for a stock truck with the 6spd(I am assuming the NV5600) which is what I have. Assuming I dont drive with a real heavy throttle of course. I like to roll into the throttle and let the turbo keep up with the fuel curve if that makes any sense.

 

I would say that is the upper end for whatwould be ok...short races...sprints etc. Just set you max boost and egt limits to resonable limits and enjoy...

If the clutch slips...then you know your still pushing the stock truck too hard.

I bet you will run out of fuel on 5/5 before anything else happens. (ie need pusher pump upgrade).

Enjoy.

 

Thanks again! I am about to order the Walbro and do Superduty's F/P upgrade.

 

on my 03 I slipped the clutch on 2/2 with the original program (like 4/2 now)

my clutch was very week

I also didnt trust my stock turbo over about 3/2 like (5/3 with new program)
some have a lot more faith in the stocker than I did, but I didnt blow it like others did either