Engine/Transmission (1998.5 - 2002) Novice needs advice

[SMcGrady]

I am having a problem with my new (to me) 2nd Gen truck. First, let me say that I am a first time CTD owner, in fact this is my first diesel vehicle of any kind. I am not very mechanically experianced, but I am not afraid to learn as I go.



Anyway, the other night when I was on the freeway with the cruise control set at 60mph, my truck started to change gears on its own, causing the cruise to disingage. I was on a long, slight decline and I could feel it shift and see my RPMs change. It would shift gears rapidly back & forth several times. I also noticed that the throttle did not seem to be responding properly during this event (kind of a mushy/lack of power feeling).



When I slowed down and revved the engine a couple of times, the truck started acting normal again. This is the first time this has happened, but I have only owned the truck for about a month and have only put about 1000 miles on it.



I have been reading through the forum and I was begining to suspect that I might be having a problem with my TPS.

• Any ideas?
  
  
  
• If it is my TPS, is this something I could/should try to replace or repair on my own (considering my lack of wrenching experiance)?
  
  
  
• If not, how much will I expect to pay to have it fixed at a shop?
  

Or am I freaking out too much and should I just chill out and wait to see if this happens again?



Thanks!



Currently Bone Stock - 1999 Dodge 2500 - CTD 24 Valve - Extend Cab - Short bed - Automatic - 2WD - 41K miles.

 

[FourBarR]

You need to get a scanner to check for codes. Generally the codes for apps (accelerator pedal position sensor)are 0121 and 0122. There is also lots of problems with the torque converter locking and on locking. This can be hard to trace. Go to the search engine on this site and enter apps and the converter problem. hope this helps.

 

[SMcGrady]

Thanks FourBarR,

If use a scanner, will it detect evidence of an intermittant problem that occured a day or two before, or do I need to have it plugged into my truck when I am actually experiancing the problem?

 

[SMcGrady]

Did it again...

It did the same thing again today on the way to work.

This time when it kicked the cruise control off it would not allow me to re-engage it, even for an instant.



There is no chattering or vibration, it just seems to have a hard time deciding which gear it wants to be in at about 60 mph.



I have orderd a code scanner and I will post the data I get from that (if my truck remains driveable until then).



I am tempted to buy one of Timbo's APPS modules, because it seems to me that would be a likely cause for my problem... (also a cheaper fix than some other suspects).



Anyone have any other ideas? I am not very experianced when it comes to wrenching and I appreciate your help.

Thx!

 

[timbo]

Scott first by checking the codes. This can be done by cycling the key on off 3 times ending with on. Than look at the odometer and write down what is says. Than go to the freq. asked questions and click on the 24V code list and you can look up what the code # means if you have any. You can also go to ADVANCE or AUTOZONE and they will plug there sanner in for free and tell you the codes. Do this, and report back... ... Tim

 

[V-Metalworx]

Scott first by checking the codes. This can be done by cycling the key on off 3 times ending with on. Than look at the odometer and write down what is says. Than go to the freq. asked questions and click on the 24V code list and you can look up what the code # means if you have any. You can also go to ADVANCE or AUTOZONE and they will plug there sanner in for free and tell you the codes. Do this, and report back... ... Tim

If he has a early 99 I don't think it will read codes with the key both of my freinds have early 99s and they won't do it but my y2k will. I've heard of the auto trucks needing to have the ecm flashed because of the converter kicking in and out could that have anything to do with it?

 

[BoeingDiesel]

Read your post and the symptoms your truck is giving seem very similar to a known problem with 99's. Check all ground connections and then wrap ( 2-times ) the battery ground wire on the turbo side with tin foil and then wrap with electrical tape or shrink wrap tape. That will inhibit the sys. from picking up noise generated by the A/C comp. If this resolves the gear searching issue ( actually sounds like TC lock / unlock ) buy a " DTT Noise Filter. " The installation is quick and easy and the problem will go away for good. As to the mushy throttle and lack of response; scanning for codes is the best way to narrow the field. Have you checked fuel pressure, filter, etc... ?

 

[SMcGrady]

got a code

Tried the turn the key off & on 3 times trick and MVandever was right... nothing. So... Went to Autozone and had them use a scanner and it pulled a

P1690 code.



The hunting problem is getting worse and does it very often now. even at lower speeds.



I am going to do a search and see what I can learn about this code.



Does anyone think that this might be related to "noise" from the alternator wire, or a bad APPS?



I intend to try wrapping the wire as suggested and it seems that I also read something about unhooking the battery then pressing on the accelerator to reset the computer... or something like that... Does this seem like a good thing to try in light of the P1690 code?

THX!

 

[timbo]

Tried the turn the key off & on 3 times trick and MVandever was right... nothing. So... Went to Autozone and had them use a scanner and it pulled a

P1690 code.



The hunting problem is getting worse and does it very often now. even at lower speeds.



I am going to do a search and see what I can learn about this code.



Does anyone think that this might be related to "noise" from the alternator wire, or a bad APPS?



I intend to try wrapping the wire as suggested and it seems that I also read something about unhooking the battery then pressing on the accelerator to reset the computer... or something like that... Does this seem like a good thing to try in light of the P1690 code?

THX!

Scott thats not a good code to have. Thats pointing toward the Injector pump.



P1690 (M) Fuel Injection Pump CKP Sensor

Does Not Agree With ECM CKP

Sensor

Problem in fuel sync signal. Possible injection pump

timing problem. Low power, engine derated, or engine

stops.

 

[SMcGrady]

Scott thats not a good code to have. Thats pointing toward the Injector pump.



P1690 (M) Fuel Injection Pump CKP Sensor

Does Not Agree With ECM CKP

Sensor

Problem in fuel sync signal. Possible injection pump

timing problem. Low power, engine derated, or engine

stops.

Tim-



would a bad injector pump give me the symptoms I've been experiancing?



or could I have a bad injector pump and an other problem too?



Thanks...

 

[timbo]

Scott, do you have a fuel press. gauge? If not you need to get one. I hate to say it but it sounds like the IP, as for the funny shifting try cleaning all your grounds.

 

[SMcGrady]

Scott, do you have a fuel press. gauge? If not you need to get one. I hate to say it but it sounds like the IP, as for the funny shifting try cleaning all your grounds.

Tim-

Do you mean a fuel pressure gauge that is installed in my truck, or a portable pressure gauge that is used as a diagnostic tool? (I have neither)

I intended to install a few gauges in the truck soon. I just bought the truck a month ago and I was in the process of learning what I could do to make it better...



Here is a little more info about the truck. I bought if from an older gentleman who used it for a while to tow his 7000 lb 5th wheel trailer. He sold the trailer a few years ago and told me that in the last 3 years he only put 5000 miles on the truck. it only had 40000 miles on it when I got it. it looks very clean and was running perfectly up until a few days ago.



In your opinion, could the p1690 code and/or the symptoms i've seen result from old fuel that sat in the tank for a long time, or a bad fuel filter?



Thanks again!

Scott-

 

[Missouri Mule]

The last time I saw a thread with 1690 code a member had not got the key in wrong while installing the vp44. Plus is engine wasn't running correctly so the 1690 mite be an old code that wasn't cleared.





SMcGrady,no old fuel would not cause it. It means that the Crank position sensors don't agree what position the crank shaft is at(the vp44 sensor and the ckp which sends info to the ECM are not in sinc) . But a crank shaft sensor going bad would cause the Torque convertor to unlock and lock but your tach would be acting up alot.

 

[SMcGrady]

Thanks Missouri Mule-



That sounds interesting... If I can clear the code and it comes back, I guess it means that there may still be a problem with my VP???



also, if my torque converter was unlocking and locking, wouldn't I be feeling a pretty heavy vibration or hit when it happened?



So my next question, to anyone, is: what is my next step to diagnose this thing? Do I have to take it to the shop, or is there something I can do myself to narrow down the possibilities and find the correct fix?



I have a deep and residing distrust of dealerships, and most repair shops, for that matter...



Thanks everyone for sticking with me on this... I sure appreciate your help!:-laf

 

[georgej]

I would do the cheap things first. Clean all battery posts and ground straps. try the tin foil wrap on the alternator wires. If this doesn't fix things replace the crank sensor. Then if it still is acting up have a diesel shop ascertain the vp has gone bad. If your mechanically able you can probably replace the vp and a lift pump yourself for less than $1300.

Good luck

 

[SMcGrady]

Sounds like a reasonable course of action.



The only thing that worries me is the 1690 code. should I not drive it until I resolve that? Can I damage my truck if the VP is really ready to take a dive?

 

[V-Metalworx]

If your vp is on it,s way out it should'nt hurt anything else it will just quit running don't give up stick with it sounds like you found a rare truck with that low of miles alittle advice I would clear the codes and drive to see if it comes back (would'nt get to far from the house)you most deffintly need to buy gauges the fuel pressure is the most important the vp trucks are really critical on fuel pressure pyro is probably the next important if you start andding mods latter then boost you should find at least a manual gauge to check your f. p. now I think genos has a fairly cheap kit and you check it right on top of your fuel filter houseing take out the ntp plug and screw in adapter the kit from genos has the adapter in it. good luck you already have the most valuable tool for your diesel truck TDR.

 

[SMcGrady]

Excellent advice!

You are right about TDR, it is the most valuable resource I've found...

Thanks!

Scott-

 

[SMcGrady]

Is a pyro gauge the same as EGT?



If so, I was thinking of going with the three gauges you mentioned. I would like to put them on the pillar and I want analog gauges. I have heard that ISSPRO gauges are a good choice. Any thoughts?



Thanks!

 

[MAleshire]

Scott, yes the pyro is an exhaust temp guage. IMHO, I recommend the fuel pressure guage, a combinaion pyro/boost guage, and a transmission fluid temp guage. Beyond that let your wallet guide you. I'm fairly new to the Cummins and TDR engine myself. One thing I've learned so far is always go with the most simple and inexpensive fixes first. These are usually the ones I can do myself, given my lack of knowledge and experience. If that doesn't work, ask for suggestions from TDR members and research the TDR archives. TDR members are great. They're a great source of knowledge and friendship. Don't just start throwing parts at a problem that's not properly diagnosed. Let TDR members know where your home town is located and they might be able to direct you to an honest and competent local diesel shop. I quickly learned where they are located around my area. The dealership wasn't one of them. If you go to a shop get it clear from the beginning who takes it in the shorts if their diagnosis is wrong and the problem doesn't get fixed. Especially when you're talking about expensive parts. Diagnosis is an art, and a good shop will stand behind their work. In addition to TDR as a resource, Buy a OEM service manual from Genos for your year of truck.



Good luck!



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