Hello all, ive been trying to figure out this problem for awhile, did tons of research and still cant track it down, so i turn to the help of experts from this forum.
This may be long but the more details i provide the better results i get i hope
2001 Dodge Ram 5.9 L Magnum, Sent my motor out to Carolina Machine Engines, And they rebuilt my motor and put in a bigger cam or RV Cam. According to them no modifications to the ECM need to be made.
From there website
"CAROLINA MACHINE ENGINES
produces a HIGH TORQUE
version of most engines. These engines are listed in our price list along with our stock engines and will have a "T" at the end of the part number. They receive a TORQUE
type camshaft sometimes called a "RV" cam. Also we perform several other operations to enhance power.
Although these engines produce more torque and horsepower, they still retain a SMOOTH IDLE and require no changes to your vehicle. They are ideal for towing and produce up to 10% more horsepower than the original engine, yet there is no change in the warranty.As a rule these engines will not affect emissions, but emissions should be verified in certain states.If you don't see the HIGH TORQUE engine you want in our price list, please call, fax or email us for more information.
So here are the symptoms and steps ive taken,
Truck starts fine and idles around 900-1200 during warmup, than 5 min or so later, idle drops down to around 500-600 RMPs, when i drive it, its seems fine, although power does not seem to be there. Pull up to stop light and it idles really low as if its gonna die, give it some juice its fine.
No Codes or MIL lights either,
Things ive done and changed.
Put in hughs plenum kit, followed torque specs to the T.
Cleaned Throttle body with Throttle Body Cleaner, wasnt to dirty to begin with.
Put in new TPS sensor, did votage test and is within specs from curb idle to WOT. So i dont think thats my problem.
Performed MAP sensor test, although it said voltage should be between 1.5 to 2 volts and as you increase RPMs it should lower voltage, well mine pretty much stays on the high side of 1.7-1.9 volts than when i increase RPMs it goes to 2 volts, instead of lowering?
Pulled out IAC motor it was clean but pintel was all the way out. Purchase a new one put it in no change, however last night i left it plugged in but removed it from Throttle body, The pintel was all the way out, I was told if i turn on the ignition it should retract and pull itself in, well it didnt, infact in whet out even farther and the spring and pintle came off? Not sure whats up with that, but gonna get another one and replace, seems like its getting stuck all the way out causing low idle?
I have not changed my IAT sensor or ECT sensor. I heard those play a roll with the IAC Motor?
Before i got the new motor, i got new O2 sensors, OEM not Bosch, i used those again, and did not replace.
New Plugs, Wires, PCV, starter, Waterpump, ....
I am using aftermarket headers on this truck brand new,
I did not have a scan tool when i did my install,
Put in distributor, follwoing manual.
TDC, all that stuff, at first it didnt start, but i realized on my TDC i was on the exhaust stroke, 180 out, fixed that started right up. Could all of this be because of a fuel sync issue? I know i can do the voltometer trick, and get it close, but seems like im pretty dang close now?
Also the Throttle body is not stock, when i got the truck it was aftermarket, but ran fine than.
My mpgs are crap, around 7mpg. And motor seems a little weak, i stomp on it and it goes but i cant even get my tires to chirp?
New catalatic converter as well.
Although symptoms show up more at a stop sign, with low idle, i can put it in park or neural and it still seems rather low, i think 700-800 should be at curb idle when warm?
Cant find any vacume leaks, as well.
Any thoughts, information im looking for is trouble shooting, or steps to confrim a part is bad, Im not going the route where people say replace this and this, its seems when i do that im throwing money out the window, with no results.
With the same motor but rebuilt, i was told by someone i need to bring it to a dealership and have them tune my computer to the new motor?
Also after replaceing most of these throttle body sensors, i unplug the battery and reset the ECM, however i have not really done and ECM relearn procedures, most i drove it was around 25 min highway speeds, drive fine, but when i come to a stop it gets the bad idle. Does this relearn procedure take awhile, and or am i not doing something correct?
Would love some input and thanks for your time.