Fed Up....Bad Miss Continued

[Blackdog]

Alright guys, I'm having the same problem as some of you are with my truck wanting to cut out around 1800-2000 RPM so it seems or approx. between 20-30lbs of boost. The truck does it also without the box but it's not nearly as noticable, with my Comp on no matter what level it will cut out extremely bad. Now, if I turn my sub-level down it seems to not do it as bad but it's still there. My fuel pressure doesnt drop below 11psi at WOT on level 5x5, so it cant be my fuel psi. Well today I replaced my MAP sensor b/c I figured it may be bad and causing it to cut back the fuel when it reaches higher boost levels, but no such luck it's still doin the same thing. I've checked those two little torx bit screws in my injection pump that Bill K. talked about and everything seems to be fine as well. I really dont see it being the Comp box b/c it was doing the same thing when I had the EZ and which both plug into the MAP sensor but like I said that must not be it. I havent had the chance to run my JVD here lately b/c we have it on a buddies truck but it did a while back when I first started having these problems with my JVD on. I may be crazy but it seems the miss isnt hardly there when the outside temps are warmer, but like I said maybe I'm just paranoid and it has been in the 20's and 30's around here lately, but last winter the truck never did this and it's setup pretty much the same except for the Comp box. Sorry for the long post but I'm gettin sick and tired of this truck actin up like this, b/c it's not even fun to drive if I cant use the power that I've got. Anyone and everyone feel free to state your opinions on what might be goin on with our trucks. Thanks

 

[Blackdog]

Could it have somthing to do with my TPS, APPS, or Camshaft position sensor??, sorry I forgot to ask in my post above. I've checked for loose connections, but just for spite I'll check them again.

 

[csutton7]

I'd be takin the stuff off and checkin to see if it 's there without it and then put one component back on and test it and so on--you should find the source of the prob----chris

 

[Marco]

Look here:

https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=34064



Maybe this will solve your problem, myabe that it will not, but it's surely worth a try.



Marco

 

[GGades]

Blackdog,

I too am fed up with this crap. On Monday I'm having my tps (apps) ,map and IAT replaced. I think I would have to agree with Marko about the timing issue as when I hook up the data port to my comp it throws everything crazy. My problem is exactly the same as yours, but it's not a harmonic type shake there's no real "rythm" to it so I am certain I can rule out any kind of driveline problem. I'll post as soon as my stuff is replaced.

 

[tmacc]

marco,

Did I see on one of the posts that the ohms values are the same for the ECT as the IAT? My IAT was well w/i the spec that you previously posted.

GGades,

Are the components you listed being replaced under warranty? If not, Save your money. If you check thru some of the shudder/bucking/hesitation threads, you'll see where folks have had those parts replaced and it did nothing. I've had the problem since last Feb. No fix yet. Has to be in the ECM. IMO I'll check the ECT when I get some specs.

Tom

 

[STRALEY]

Same problem here

Mine does it bad between 2200-2700 RPM. After 2700, hang on, that is in 5th with comp on 5x5. 44#s of boost and heck of a ride. But in that 500 RPM range it misses bad. Bad enough that when I blow someone away, I don't want them to hear my truck doing that. It isn't the shudder-stumble I used to have. When I ran the VA and the Comp it was real bad on 5x5, no matter what RPM, 1600 and above, even cruising gently. I know right now that I need my Comp replaced as I can nver adjust it without shutting it off then turning it back on, but the problem existed way before this power setting thing. I've ran 3 different HOT Comps and it has existed on all three. One ran great, but still not quite to par. I know it is definetly better without the VA but am not sure what it is. I know I have fuel pressure as well as Eric does. Wish it was a simple fix, since alot of people that run boxes have the same or close to same problem.



Jeremy

 

[bow hunter]

Just a idea, check the torque on the high pressure nuts for injection lines. the out side ones?

 

[GGades]

tmacc, been having trouble with accelerator pedal going dead while driving. Codes came up for apps and map being out of voltage specs. Warranty will cover that problem anyway. Are most of us with troubles using the comp box or are the other boxes giving trouble as well.

 

[csutton7]

maybe my line of thinking is wacko--but doesn't the VA do what the EZ does basically---and doesn't the Comp have the EZ built into it---why would you pair a Comp and VA or Comp & EZ or Comp and something else together---seems something would not work right----thus the Comp working better without the VA-- I'd think you probably didn't do the Comp any good by running that combo---am I way off base here???... ... . chris

 

[John]

That's exactly what I was thinking Chris!



Stacking two different timing modules is asking for trouble! It's the, I'll see you, and raise you (double ) theory.

 

[HVAC]

Chris, you may be referring to CumminsTurbo425. I'd have to agree with you about stacking redundant boxes. Also, too much advance is very hard on the head gasket.

 

[STRALEY]

Ummm

Thats why it isn't on there anymore, can't say that I knew any better when it was done and the VA is what i put on right after I bought the truck so I already had it. But like I said in previous post, the VA is not on... either way I still have problems with any box I run.

 

[Diesel Freak]

whatever you do, do not stack boxes that attach to the DATA PORT, and the Pump CAN plug. If you do that, the resulting garbled signal on the CAN will be unreadable to the VP44 and the ECM. . remember the old computer acromym. . GIGO?. . this will most likely set a number of trouble codes, and shut down the engine. You will have to take it to the dealer to get the codes cleared just to make sure you did not scramble any of the electronics. There is a set limit to the possible number of bit code possibilities that are recognizable to the VP44 FPCM... Joe Donneley gave a very basic overview of this in the current TDR Mag.



here is a little more indepth explanation on how the J1939 29 bit protocol communicates



J1939 uses the 29 bit identifier defined within the CAN protocol shown in Figure 2. The SOF, SRR, I DE, and RTR bits will be ignored in the following description. The first 3 bits are used for determining message priority during the arbitration process. A value of 000 has the highest priority. Higher priority messages would typically be used for high speed control messages. An example of this is the torque control message from the transmission to the engine. A lower priority would be used for data which is not time critical. An example of this vehicle road speed. The priority field should be programmable for each DC value so that network tuning can be performed by an OEM if necessary.

The next bit of the identifier is reserved. The bit should be set to 0 for transmitted messages. This default will permit future use of the bit for other purposes as defined by the SAE committee.

The next set of 9 bits in the identifier is the Data Content (DC) field. The DC field identifies what data is contained within the message. The first bit is used as a page selector. The later 8 bits provide a page of 256 different values. Page 0 is intended to contain all the messages which are presently being defined. Page 1 is intended to provide additional expansion capacity for the future. Data Content values will be discussed further in section 3. 2. 1 and in J1939/2, Section 4. 4. 4.

The next 8 bits of the identifier are PDU specific (dependent on the message format). If the data content value is between 0 and 239,this field contains a destination address(PDU1). If the data content field is between 240 and 255, this field contains an extended data content (PDU2). This provides a larger set of values to identity different broadcast data.

The last 8 bits of the identifier contain the address of the device transmitting the message. For a given network, every address must be unique (256 available). This means that two different devices (ECUS) cannot use the same address.

 

[tmacc]

GGades,

Folks w/ EZ's are complaining about the same thing. I noticed mine truck hesitating after the #018-24-01 trans re-flash. (It was probably doing it before, but I didn't notice it at the time) My truck was bone stock at the time. Very noticable at 1700 rpm, which is 55 mph. Almost goes away after the temps hit 70* or so. It was very suttle(sp?), but it was definetely there. The EZ just acserbates the problem. Doesn't buck real bad like some of the folks have complained about, but it's sure annoying.

 

[Blackdog]

Well I've replaced my MAP sensor and my ECT now, I havent had a chance to drive it since I replaced my ECT sensor. But i'm goin to here in a few minutes. If I get time I'll post my results later on this evening. If this don't work I guess I'm gonna have to spend the money on the new TPS (APPS). Pray for me!. Take care!

 

[RAPID RICK]

buck-n-jerk

I've replaced the APPS,lift pump & map sensor all to no avail. Still does the same damn thing as before I replaced all that crap. Rick

 

[Blackdog]

Well my short 20 minute drive really didnt tell me a whole lot, but it has been warmer today and this evening in the high 50's. The problem didnt seem to be as bad but like I said it's warmer and I've noticed the problems when it's colder out. Hopefully it will get colder that way I'll know for sure if the ECT fixed my problem. I"ll report back when I have some more info. Take care!

 

[GGades]

Has anyone found a cure yet . I've replaced the apps, map iat and coolant sender and still nothing. Also have tried different boxes all with the same result (banks ottomind, power edge comp and tst pm3) comp seems to shake the worst. Need help! HELP HELP HELP HELP ANYBODY

 

[rubberneck]

timing

I think marco is on the money here guys. I think there is an issue with the timing maps in the programing in our trucks. Think about it everyone complains it gets worse when we put a "timing" box the va, the ez and the comp box all advance timing. In the cold weather our problem is worse. I believe marco stated in the earlier thread that what is possibly happening is we are getting too much advance in the colder weather. I know my bucking is reduced without the ez on. I dont think it is our boxes, because like others i have tried multiple brands, but it is in the truck. Now the million dollar question is why did the truck not do it when new. (mine started at 9k miles). I guess you could make an argument that the ecm is recognizing the out of spec timing and storing that info, but then why dont all of us have this problem, and why did reflashing my ecm not work "for a while". I know personally at least 6 or 7 guys running timing boxes around my area and i know there are probably hundreds more, i dont hear of them complaining. I guess it is only us lucky few. could it be fuel i dont know, i but from a huge truck stop that moves some serious volume.