Hey guys, this questions about my 01 24v, basically stock except intake/exhaust . . and we just put a TST on it.

Something doesn't seem right. Its like its just not fueling very much at all. Now my other truck is a 98.5 24v and I have a intake/exhaust, FASS, and quadzilla adrenaline with the torque tune on it.

My problem in all honesty may be that I'm just used to the quad on my 98 and a TST on the 01 just doesn't compare at all, idk.

The 01 with the TST only hits 24 lbs of boost with the wastegate plugged? That seems fairly low (I think) Isn't stock boost like 18ish? Too only go to 24 lbs after plugging the wastegate and putting on this so called 120 horse 380 ft lb TST programmer seems off?

My quad hits 40 all day long (stock turbo/injectors) with no wastegate mods

Something else that is odd is every once and a while the 01 TST truck seems like it'll get a shot of juice just randomly while driving and open up some times, I happened to be looking down once when it did and it hit 27 psi and I wasn't even at full throttle, when at other times you have to make her work all out to hit that 24 psi mark . . .



OK, so I then thought, bad wire tap at the vp, redid the tap twice, even moved down the wire and tapped it again in another spot and still acting the same . . . any input? Don't wanna tear this wire up anymore if I can help it, its a small wire on a very expensive piece, ha.



Any tips? Thanks guys

 

i dont think its an issue with your wire tap. 24 is not much of a number for a programmer.

 

Um i bet your starving your vp of fuel.

 

Stock lift pump? Any idea what fuel pressure is? Any codes

 

Yea, this might be one of those smack myself in the head instances, it is a stock lift pump, kinda had the impression from various folk that you could get away with a stock lift pump with just a programmer, it was when you went to injectors that you had to upgrade, but that may be a misinformed theory there.

No Codes bein thrown

 

Okay, lets see if I got this right, low boost of 24 lbs and doesnt seem to be fueling? Ill try helping you trouble shoot this, first, there should be three lights on the box itself, a red, yellow and green. Red means the box has a 12 volt source, this should be on at all times while key is on with the box turned on as well, the yellow means the box is reading a boost signal from the MAP sensor, this should be on anytime the truck is running as it means its reading the boost pressure, even if its 0, itll get brighter as more boost is added to the motor, the green light is big one where often times people have problems getting, it should not be on at idle or when the key is on but the motor is off. This light shows when the TST PM3 is adding power to the VP44. If you do not have a light, double check the tap into the VP44, im not sure how old your box is, but the harness connections were changed not to long ago from the old style crimp connectors to a posi-tap, i reccomend the posi-tap vs the old style. if you still do not have a green light while motor is running and you are driving, then you need to locate where fuse holder is for the VP wire, it should be black and located just behind the big multi-prong connector, check this fuse, it is the old tube style fuse, it should be 5 amps and not blown., if it is blown change it. then drive truck some more, if you still dont get a light, check the multi-prong connector for tightness. if you still cant get a light, pm me and ill help you work through it.

Now for some questions, you say plugged wastegate, did you adjust the boost elbow sent with TST kit, i believe that elbow is set to start opening the waste gate at around 28lbs with full opening at 36lbs,? also have you checked for leaks on your intercooler boots and clamps?

I see where you are running a stock lift pump, this is probably your problem as the amount of fuel the TST box can push will greatly exceed the amounts the factory lift pump can flow, especially if its the intank version. If at idle, your fuel pressure is below 10, you need to change that out, if its above 10psi but drops as soon as you mash the go pedal, then its time for a better lift pump. anything below 7 psi can cause big time damage to your injection pump. I would reccomend a Airdog, raptor, FASS aftermarket pump. my stock 99 has a raptor 150 with adjustable pressure, my modded truck runs a FASS pump, both work great, raptor is a tad cheaper and easier to install in my opinion. as far as flow rate, Id go at to a 150is gph pump to allow you some breathing room should eventually you put more upgrades on

As far as the notion you can run a programmer with a stock lift pump, does not work in my experience. I used to have a 98.5 24 valve and even without a box, the stock lift pump couldnt hold more thant 8 psi going down the road at 60mph, any faster and itd drop to 3. Youre asking for some serious trouble down the road if you run a box on the stock lift pump. it may work initially or seem to but you can bet that eventually it'll eat the stock lift pump for lunch and may even kill the VP44 injection pump for an evening snack regardless of who makes the box. I would reccomend swapping that lift pump out as soon as you can afford too. Also for the time being, I would stay off the upper levels of that box or even not run the box until doing such for fear of a very expensive injection pump replacement.

If you need any other help on the TST box and troubleshooting it, let me know. but first off, id rig up a way to test the fuel pressure you have before doing anything else

 

Yea the lights are lighting up, Red on no probs, yellow comes on although doesnt seem to change brightness at all, green light for fuel seems weak but that may just be me, it does go off and on as you hammer down though.

On the wastegate, didn't even mess with it as the turbo was already plugged, fairly certain it isnt leaking boost anywhere, probably wouldn't hurt if i did the old soapy water check thou.

But most likely it is the pump,

It is an in tank, and it and the VP are probably 6 months old they both died at the same time a little while ago, so trust me, right there with you on not killing the VP again. We've turned the box down to 2 and don't plan on turning it up until an airdog or similar goes in, besides it really doesn't matter if we turn it up anyway the thing just isn't getting any fuel so it barely makes a difference. Probably the cheap autozone stock replacement lift pump doing an "o so awesome" job of not fueling, ha.

 

The green one will flicker as it adds fuel and what you're seeing is the pulses of the pump. Id say then that you don't have enough fuel to supply the pump as you have said.

We did find something weird on the dyno last week, we plugged the wastegate on the stock truck and lost 34 hp with the box. Put an adjustable boost elbow on and gained back that 34 plus 20 more. Never did figure out why it did it

 

10-4, thanks for the tip and advice so far, we'll see what happens when we get an airdog on the thing, in the process of putting some Fab Fours Bumpers on both Trucks so the Airdog might have to wait just a bit

 

That's cool, just be aware that even without the tst box on, that factory pump may not be giving the vp 44 enough fuel to cool it and prevent a failure. My advice is that even with out a box, you need to run a better pump. Now what you could do is make your own test gauge for fuel pressure. There's a write up on here about it, he made it for 25 bucks. Factory calls for replacement of the pump at 7 psi while running, anything below 5 psi and you best start saving pennies for a new vp44