Its like it floats the valves.We own 5 CTD's(93-99,160-450k) and they dont seem to do it till the milage gets up there(150k+)The 12 valves float at around 1700 I think....Been a while since ive driven any of them.I inherited the trucks from my father and when I drove the 99 last week,it did this.Under 2200 and its fine...

Im about to start driving/modding the 99 ext cab 5 speed 2500 work truck and I want to get it running 100% before I start driving it.

I want to go as fast as the stock turbo will take me.Maybe another turbo down the road but not likely.I already have 2 GN's,I just want somthing thatll still show those pesky ricers theyre weak WHILE towing a GN


BTW,been a lurker here for a while and the sites great BUT YOU GUYS NEED A STICKY WITH WHAT ALL THOSE ABBREVIATIONS MEAN!!!I dont know one part from the next and it seems the search is down...

 

For a description of the abbreviations look here:https://www.dieseltruckresource.com/...n&onlynewfaq=1
What do you mean when you say the 12v engine 'floats' at 1700 rpm? Generally the governor in the pump starts to de-fuel at about 2200 rpm. Is that what you are feeling?
Tom

 

Thanks for the link...

What I mean by floats is it seems like it floats the valves,like a gasoline engine w/ a hyd cam.

None of our CTD's will hit redline like they did when newer(under 150k)

I just ordered a FASS and full MBRP exhaust so well see how those 2 help out.

 

Sounds like the timing has slipped on the 12v's, but I have no idea why the 24v would act the same.

Chris

 

I had my CTD in to the dealer today to have my IP replaced. I was talking to mechanic and he was explaining to me the symptoms of a failed IP. Guess what? He said one of the more common symptoms is "can't rev over 2200 rpm". Very similar symptoms to yours.

 

Thats what I was thinking...Im gonna install the FASS to eliminate the lift pump and the dp/exhasut to eleminate any blockage in the exhaust.

If those dont fix it,ill replace the IP.

I want a fire breathing Cummins

BTW,how does the timing "slip"?

 

I bought my 99 Cummins Dodge with 36000 mi. and it never has gone over 2100 RPM no matter how hard I try. It now has 56000 and I lost the tranny today. About 3 months ago I replaced the lift pump. So are you guys saying it should go over that RPM? I know that is dumb ? but no one has given me a straight answer so far locally. And anyone have any suggestions for a tranny?

 

I dont know what I would do if I couldnt get my truck over 2200 rpm. I love to watch the expressions on peoples faces when they have their drivers window down and I downshift into 3rd at about 30 mph I would say there is there is a problem with the IP but thats just an educated guess.

 

The CTD engines will rev to 3450 rpm +/- 50, determined by the rev limiter, 2200 rpm limit is a problem. According to the diesel mechanic working on my truck " (he replaced my IP) one of the most common symptoms of a IP failure is the inability to rev over 2200 rpm".
Check your codes there should be none. If you have a 216 code this is death code for IPs. If you have no codes or even if you do take it to the dealer and have him check it. You don't have to have the work done but it will determine where the problem is.
Good luck
Grim Reaper.

 

I have checked the codes and it has none. Maybe I will just have to trade it on a new one!!!!!!

 

One more reason to put a fuel gauge on these beasts. If you don't have an FP guage on your Cummins do it now. Order it now and avoid a $1,200 IP replacement.

Original VP-44 with 180K miles.

 

Why not take it in and have a diesel mechanic check it out. That way you'll know for sure what your problem is.