Engine/Transmission (1998.5 - 2002) gutless bl##y wonder

[2-ND TIME]

Why is it that I have the worst truck in North America :{ :-{} For I can't seem to find a diesel mech that I think that he knows what he is talking about. Anyone who reads this please answer if there truck doesn't build power (increase fueling) when the step on the throttle! THis thing I have been stuck with reves up like a sewing machine, but DOESN'T GIVE ME MORE POWER :{ fOR It is embarasing to be passed by a Dodge that is pulling a 27' 5TH WHEEL where I can't pass because of lack of power. Have even been passed by a loaded tanker going uphill what gives??????? Had trouble getting ahead of a gas pot 2500 Chev pulling a 21' fifth last year at a light????? I even had the P-N-P in the dog meat too. 99,24V3500 4x4 5spd. PS Been like this since NEW. :--)

 

[blowinsmoke]

does it smoke at all? is it hard to start after fuel filter changes? if it is you've got a fuel problem (lift pump, inj pump)

 

[Big_Daddy_T]

Id find a cummins dealer. Quick before you start getting crazy thoughts. Like. Shoulda got a powerstroke. Sounds like a fuel problem though. Ive heard of algae in the tank causing poor acceleration.

 

[2-ND TIME]

gutless

Sorry not algee not pluged fuel filter or air. And no cummins is nooooooo better at reconizing what a problem is the dyno guys missed the fact that the engine was overheating and the t-stat needed to be replaced engine temp was 243*f and that the rad was 114* and the bottom was 86*f the only way they did pickup the % throttle % hp it was about 70% throttle and 100 hp. There is noooooo initial fueling off idle and so nooooooo more power. If the ecm can't see a change of state from the APPS there is no signal to the fpcm so there is no increase in fuelling until the signal from the maps comes in and wakes things up a l i t t le :-laf a n d you slowly start to labour off. It has always taken about 1000 rpm to shift on any kind of grade. and by this time people are going past me. Thats my take on it.

 

[jmeehan]

Do you have any codes? I don't know how the ecm works as far as storing and showing codes but, if there's a problem with the ecm it may not show codes. Other then swapping parts with a good running truck I wouldn't know how to verify if the ecm is good or not.

 

[SKneeland]

"THis thing I have been stuck with reves up like a sewing machine, but DOESN'T GIVE ME MORE POWER"



your sig. shows 5spd, what gives?, if its revving up but not transfering power to the ground, is something slipping?

 

[Steve St.Laurent]

I'm confused by your "it takes 1000 rpm to shift" comment - what do you mean by that? Do you have gauges? What are you seeing for boost and egt's peak and cruising down the highway? How about fuel pressures (cruise and wot)? Your last post is really confusing to me. You mention being on a dyno - "And no cummins is nooooooo better at reconizing what a problem is the dyno guys missed the fact that the engine was overheating and the t-stat needed to be replaced engine temp was 243*f and that the rad was 114* and the bottom was 86*f the only way they did pickup the % throttle % hp it was about 70% throttle and 100 hp" I can't understand anything out of that other than that the truck overheated. Did it only put out 100hp on the dyno? Did the throttle only hit 70% max? Fill in some of these details and we'll see what we can do to help.

 

[2-ND TIME]

Let me see what I can remember what was asked of me. Lift pump fuel pressure was 14. 5 lbs " pre" when the last LP was put in and so it runs at 12. 5 "post" lbs. and at WOT is is now down to 10 lbs. I can rev it to max RPM with no prob. But it has always had a non standard diesel shake form misfiring or incomplete diesel injection cycle. On one of the dyno they discovered not full HP to throttle responce they changed the MAP and it was better,for they didn't want me there in the dyno area to see the later run. But not what I thought diesel performance acceleration should be. For they test upper end HP and that isn't where the problem starts is as far as Iam concerened. It starts with initial fueling"lack there of". If you aren't looking in the right area one isn't going to find a problem. I explained this to another Dog dealer and they wanted to do it there way so had to explain it to them again and Danny said that they could try it. Why do they have to reinvent the wheel!!!!! The cummins mech said the other day that most people look for things that are too complicated that they should stick with the simple things. That has already been done many times. This is my 5 th lift pump and this one seems to be good so far. Have pre and post pressure senders and wired to one gauge. Why does an engine cutout( just like turning the switch off for a nano second) at 2200 rpm and under good load up a 10% grade? Thanks for the info. .

 

[Steve St.Laurent]

How about boost and egt numbers both at WOT and at a steady cruise? Has anyone checked out the APPS (throttle position sensor)? That can be read by any scan tool to make sure it's accurately working (0-100%).



btw, I see no drop at all across my fuel filter (pre and post read identical) with a fresh filter and I can tell a noticeable performance drop with a 2 psi drop across the filter (I change it at 2 psi difference).

 

[2-ND TIME]

engine problerms

The boost can come on start in 4 th gear but you won't get any in 1st, 2nd maybe 5 lbs in 3 rd gear then starts to labour in 4th and at about 1400 it starts to pickup some what. If I am doing a hill it is slow to come on but will pick up but others are passing me by this time. Fuel filter pressure is good and no new filters don't change the lack of performance at all and air filters don't either. As far as the APPS is concerned this is what I think is the problem with reference to cummins 99 wiring diagram bulliten #3666480 the pins #1-2 and 1-6 the on and off idle there spec's says <125 ohms and mine measures 2. 65 meg ohms of the 8 that I have measured they range from 2564 ohms to 13. ?? meg ohms and (no) change of state with the off-idle pins 1-2 so although the DRB can see achange of state of the apps I question that the ECM isn't seeing the change of state and is giving fuel accordingly. For this is (exactly what it is doing) I am not going to buy anymore parts till I can find the real problem and it can be fixed. I have WASTED over about $10,000 on this factory problem.

 

[SnoKing]

Did you check if a intake hose blew off, check all the hoses from the turbo to the intake horn. Also look where the inter fender sheet metal in close to the hoses on both sides to make sure that it has not worn a hole in the hose. If you remove the hose going into the turbo from the filter box, can you spin the turbo with your finger? Did you remove the intake snorkle boot from the airbox to fender? You should see boost go up in any gear shortly after hitting the trottle! SNOKNG

 

[Steve St.Laurent]

What are the actual boost and EGT numbers? As in - cruising down the road at 70 mph unloaded I'm seeing 7 psi of boost and ~750 degrees. At WOT I'm hitting 20 psi of boost and a peak of 1250 degrees, etc. We really need the numbers.

 

[CATCRACKER]

all i can say is i have a headache from trying to make sense of some of these posts. make sure on your fuel tank they took the read nipple off of the tank so that is can breathe properly. these were dust caps and many got left on at the factory. probably not the prob but check it anyway

 

[TMWeber]

I thought my truck was gutless then I found that the wastegage actuator rod was not connected to the wastegate and so nothing was keeping the gate closed. Boost was escaping out the gate freely. Closed the gate and HUGE difference.

 

[SKneeland]

i experienced some of those problems when i had a faulty thottle position sensor, engine cutting out and gas pedal position not equalling the appropriate engine output. mine showed up in the codes, couldnt hurt to look into it though.

 

[matches]

All these replies are good, but I would try with the air problem first. Can you hear the turbo spool at all? If so you need to check all the boots and hoses like stated before, and have your intercooler pressure checked, if you are loosing your boost, wich it sounds like, you would have the problems you are experiencing. Also, forgive my ignorance, but your injector pump may have a metal boost tube that is cracked and fooling your pump so-to-speek. I would check the other first, you should be making boost. If your not making boost you should really monitor your egts, because they will go sky high. I hope this helps.

 

[Ron Bissett]

clean the AIT ? check the AIT. ? OR are you just blowing smoke on us. ? Ron Bissett in Metro Louisville KY

 

[JoshPeters]

OK, low boost... Good fuel pressure. You said you have a sensor that is reading improperly. I would start there. I would take your DVOM find your TPS, have someone in the cab, and S L O W L Y put the pedal to the floor. Watch your voltage, it should slowly change. If it dropps off or doesn't change... you have a bad TPS. If when the "driver" has his foot on the floor and you can grab the linkage and move it more towards WOT, You have a linkage issue. I wish I had a good scan tool, about 40 min and lived closer. We'd have this thing licked in no time.



Josh

 

[2-ND TIME]

G.b.w.

Shall try to remember what everyone has asked me. I can spin the turbo with my finger seems all right to me. Haven't got a pyro yet so can't talk numbers but, the few times that have done a hill and jumped out to infrared the manifold it was a little over 400*f Have thought of temp sticks but only can buy abox of them so no joy there. At 60 MPH I do about 3 to 4 lbs boost. Haven't pressure tested the intercooler but don't think the problem is there. Sometimes the fuel tank seems to be under pressure or vacuum but even with the cap sitting on top it doesn't change the way it runs. Boost is very slow to come on and labours greatly getting going. On testing the APPS have tested the off-idle valadation cct and this is were all the resistance is that shouldn't be. I thought that the other part of it had chips in it and didn't test very well. Anatomy of an APPS.

 

[Steve St.Laurent]

I'll ask once more - what is the peak boost that you see? Also, does it stay there or does it bleed off (while maintaining WOT)? Next time you drive try this - in 4th gear at 1200 rpm floor it quickly and take note of what rpm your boost hits it's peak and let us know the rpm and what that peak is - also if it starts lowering after hitting it and what it lowers down to.



An infrared reading of the exhaust manifold isn't going to tell you anything - an egt gauge might.