Archived MAP SENSOR? terrible throttle response, bucking & surging

[Weidner]

My 01 eth with DD3's and Edge Comp is undrivable. It has terrrible throttle response - almost like dead spots in the throttle. It will lose all response when reving up in neutral and while driving, then kick in an roar away for a minute, than back to little or no throttle. The funniest thing is, after I get it to like 50 mph or so (5th or 6th gear) it drove smoothe with the cruse on and would accelorate and decelorate with the cruse controls. It first set a code for apps (I had some other problems with the just apps setting codes and going to a limp mode that I could cure with a re start, so I replaced that first) . After replacing the apps, I test drove it and it drove better for the first 1/2 mile, than back at it again. Checked the codes again and now a map sensor code is set. Boost gauge seems normal, I have always tried in the dark and the smoke looks normal, fuel pressure is good and I just replaced the fuel filter when I did the apps.



I checked my comp wiring going to the map sensor and it all looks good. Do I just replace the map sensor and hope that fixes it? After writing the check for the new apps, I am not real eager to feed this thing new parts. Is there a way to check the map sensor for sure to see if it is bad, or can I bypass my comp wiring and plug the stock harness back into the map sensor without upsetting anything else?



Any suggestions?

 

[CORed]

I've heard of guys cleaning their MAP sensors with mixed results. They have also had problems similar to what you describe where the ground to the Edge Comp was bad or the connection to the MAP sensor was bad. Clean both connections at a minimum. Then try cleaning the MAP. If it doesn't completely solve it, you may need a new MAP sensor. Get it from the Cummins dealer and save yourself some money.



Good luck!

 

[2-ND TIME]

engine bucking

Sounds as if your APPS is bad I have measured 8 so far and they all measure way above the minimum contact resistance required by Cummins . Get the wiring diagram from cummins and that will give you the nessecary spects for APPS contact resistances. For I have found that I can wind mine uup to 2700 in 3 rd gear and get 3/4 lbs of boost talk about gutless :-{} I have always had to be on the throttle every nano second to keep it from bucking. :{ Take the MAP out and measure the resistance of the three pins draw a diagram of the resistances and fill in the numbers mine were all within 400 ohms of each other so they were fine .

 

[Weidner]

I will be taking the map sensor out tonight for testing/cleaning. I have a new one I picked up just in case. I guess with 130K on this thing, its time for some little things to wear out.

 

[Weidner]

Still not running...need help, I am stumped

Put in a new map sensor, same problem. Removed the Edge Comp, still same problem. Double checked the plugs for the Map sensor and apps, both show no signs of corosion and the wires all look good.



It drives fine on crusie, I think that is a give away to the problem, but I can't figure it out. Reading about the PCM in the service manual it says in cruse mode that it is a closed loop mode, verses acceleration, when it is an open loop. I have a new code in the system 522, that leads me to the ecu or pcm, as of now codes 236 (map sensor too high too long) 522 (oil pressure sensor voltage input below acceptable level) 122 (apps sensor voltage input below acceptable level) with two codes showing input voltage too low, I think my problem might be from where those voltages to the sensors are supplied from (pcm or ecu not sure). I am topping $500 in test parts and now my checking accout and parience are running out. Could the low voltage problems be caused by bad batteries? It has been slow to start for a while and I have been expecting to get new batteries soon - is that my next step?



I need some of the experienced pros out there to help on this with some advise. Where are you guys at?

 

[Black-Smoker]

The new batteries cant hurt you need them any way. I had similar dead throttle spots in mine a few years back and it turned out to be a bad throttle position sensor. It is worth checking.

 

[2-ND TIME]

Bucking engiene

Don't know if your is exactly the same but they should be but the specs for the APPS are.

5 VDC Power supply ( Sensor and Switch) @ ECM 4. 75 to 5. 25 VDC

@ Harness 4. 50 to 5. 25 I had 5. 03 VDC on pin 5 of APPS and 4. 71 on pin ??? 2. Hope this helps. Measure the pins 1/2 and 1/6 see what you get for resistance on them and as you advance the apps I am very interested on pins 1/2. Hope this helps.

 

[TurboDog]

Did you leave the batteries unhooked overnight when you unhooked the edge comp? That is the only way I have been able to get back to running correctly, after each of the episodes I have had with mine. My batteries are couple years old, maybe three, but seem to working fine. I sure would like to try my VA hooked up again, but just don't need the headache right now! Let us know what you find out.

 

[KDoerr]

Check the injector pump I Have the same thing and we found it was the pump

 

[TurboDog]

Check the inj Pump? How? Did it need to be replaced or was there a wiring issue with it? Mine has similar problems as Weidner's and I am following this thread closely. Thanks.

 

[GatorRam]

Mine has been doing a similar thing, it seems to get worse as it gets colder. Check out this parts list: 3 VP's, new comp, turbo, MAP sensor, IAT sensor, APPS, etc. and it still does it. The only thing that I haven't tried is to solder an extension to the Comp ground and hook it right to the battery. I've heard this helps but I don't see how being that I get the same readings in that location and where it is presently grounded with a multimeter. Another thing now that you speak of batteries, mine are just 2 years old and they are already on the way out. The truck will barely turn over when it is cold. The thing that is so aggrivating about this is the truck did not use to do this and now when I roll on the throttle the bucking is so bad I can't drive it. Sorry for rambling but I hope we can get this figured out because it is driving a lot of people nuts.



Adam

 

[Weidner]

Gator, have you tried to set cruise control and accelerate from that. Thats what I have to do to drive mine. I will be working on it tonight though. Going to check all grounds including ecu and install fresh batteries. I will report if I have any changes in the situation.

 

[Weidner]

new ecm fixed my truck.

 

[2-ND TIME]

99 garbage

Well a new ECM only lightened my wallet $$3000. 00 and didn't fix this 99 junk of garbage!!!!!!!! Adam with using the multimeter to ground you are using a high resistance to ground . Mine when it was measured the ground ccts were 0. 300 ohms so I saw it as a waste of my time and of my money and it didn't fix the problem. They have no knowledge of how to do a good job on these trucks. His hack job and splice job was poor and he used some crappy wire on it so I had him take it out since it changed the resisatance so little that it wasn't worth it. Transistors can work just fine with that resistance. With after the years of watching what they do and do or don't try they really have no knowledge of how to analize something not being able to re&re something. Even with the (help) of there tech line. Last cryslurr cummins I buy!!!!!!!!!!!!!! :-{}