2GN.ORG

^^ Great.. I thought I was onto something. Way to burst my bubble

Just had my PCM updated. No codes yet!!! Hopefully it will stay that way. I didn't notice any extra performance/responsiveness increase that others mentioned. Oh well.

Probably because you have a different year an a non Magnum PCM

Well the check engine light came on again after the reflash Any suggestions?

look into one of the fixes i posted from srtforums.

I read the links you posted, but they all seem very specific to the SRT4.

I was thinking about the map clamp. Now I dont know much about them, but I thought they are only designed to work with high boost levels. How would that help in my situation?

I had a MAP clamp also, didn't help.

Their suppose to be able to send the signal back to the ECU that is equal to what the ecu would normal recieve with the stock TB.

Didnt work on mine either

Well i put the stock TB back on. Got sick of the check engine light comming on. I'm still gonna try and fix my 60mm eventully. Not too sure how though. Stupid NGC PCM. You'd almost think that DCX didn't want us modding our Neons

^^^
In a sence that is correct, but one thing someone has not looked into is that its possible that the 60mm is too big, try to experiment with something like a 55-58mm TB. I know there is no aftermarket support for it but get creative to test it.
As mentioned also before, the NGC pcm is very sensitve to drastic changes. Since your inducing all that airflow, the pcm probably thinks the bellows tube has a hole in it.
There's a topic here somewhere about TB sizing and the 2.0 airflow requirements. Its been proven that on a stock internal motor the 60mm is to big and flows to much air...

Sell em the Lorenzo for 20$

no seriously - but BRR, you said something a 55-58mm TB, is there any that fit our Neon that is from another dodge? Like with the first gen and the mtx/atx tb swap? Or is this undiscovered country yet?

kc2002acr wrote:Sell em the Lorenzo for 20$

You wish


No check engine light today with the stock TB. Doens't sound nearly as good. I didn't really notice any loss in performace. Probably need a dyno to know for sure.

I'm gonna try the 60mm again this weekend and see if I can get it to work. I have a few ideas that I want to try before I completly give up.

My uncle owns his own CNC machine (I think thats what its called). I should see if he can make a TB between 55mm and 58mm. Would there be any interest in this if it didn't throw codes? If I could get enough people for him to make a nice profit he might consider the project. Let me know everyone.

Yes - I would. Especially if it was tested and found to have no problems.

So I am new to this forum and the whole forum, but I have tried to read all info that I can on this issue. Recently I took a trip to Seattle which is about 8 to 10 hours a way. I have cai unorthodox udp and a new mpx tb. I have had my tb on my car for about 3 weeks now. I had no issues til i took my trip either. Well driving down the road i get the 0068 issues not once not twice but three times. Each time i turned the car off then back on and the limp mode went away but the cel light did not. I was able to get to seattle in the end and removed the battery cable to reset the computer for about 10 minutes or more. light went off no prob when driving back to where i live in Boise ID i noticed that the issue does not occur at all ie no light no limp(btw i hate limp mode) it was not until i kept the rpm's above 3500 for an extended period of time. Not sure how much time. But none the less the issue wont occur in the car at low speeds either. the whole trip back i kept rpm 3500 or less and had no issue was able to go over but just to pass people(stupid slow people) I did not attempt to see if the issue happens at over 3500 rpms in 4th but it does in 5th. I went to a dealership in seattle to have them do the pcm flash and they wanted the car for 3/4 of the day and then charge 99 dollars(f-them) By the way with udp's ac power steering belt is 500k4 or maybe 505k4 and alternator belt size 327k4 or below. I had one break on mean while on the coast 50 miles from no where replaced because i had another one i would reccomend 320k4 maybe 315k4 but nothing less than that i wish unorthodox told you which specific belts to get. They do but in a general range. By the way i do have one of the "special" 2003 r/t's

bostwick763 wrote:By the way i do have one of the "special" 2003 r/t's

I'm gonna save you a lot of time and hastle. Just sell the TB cause you ain't never gonna get rid of the check engine light! I tried and tried but it just kept comming back.

You can sell it on here in about 5 min and make pretty good money

Good luck to you and welcome to 2gn

daaboots wrote:

bostwick763 wrote:By the way i do have one of the "special" 2003 r/t's

I'm gonna save you a lot of time and hastle. Just sell the TB cause you ain't never gonna get rid of the check engine light! I tried and tried but it just kept comming back.

You can sell it on here in about 5 min and make pretty good money

Good luck to you and welcome to 2gn

Exactly

03 R/T = No Aftermarket TBs

Its an NGC related issue that no one has figured out yet...

what about getting an 04 R/T Ecu and reprograming the 03 R/T VIN into it.

^^^
Its possible to do that, but the 03 guys are having the same problem too...

we know the 03 guys are having the issue..

"Rise from your grave!"

Does anyone still have their 60mm throttle body?
I have been doing alot of reading into this lately. Mostly because i am a little worried that my srt throttle body project may suffer the same fate.

I have been thinking about all of the major parts of the throttle body. One of which came to mind was the throttle position sensor. Basically this sensor is nothing but an overgrown potentiometer and in our case contains a feedback loop.

see
http://en.wikipedia.org/wiki/Throttle_position_sensor
http://www.autoshop101.com/forms/h33.pdf


P0068 is quite simply an error that the TPS values are not correlating(complimenting) the values given by the MAP sensor to the ECU.

The SRT ECU obviously does differ in the fact that the air intake is interpreted as boost. However they can still receive the same error. This is interpreted by the ECU as partial throttle boost (PTB). The ECU is actually protecting the car and driver from having too much boost inside of the engine while at idle or low RPM. Think of this scenario: You are driving slow and tons of boost goes into the engine when you simply dont want it.

I have been thinking. The TPS mod should help ailing NGC users. The mod simply modifies the feedback loop to trick the ecu into thinking that the butterfly is closed more than it actually is. Thus making the TPS and MAP readings play nice.

so my point is. Has anyone tried the TPS mod while using their 60mm TB yet?

well i doubt it's a 2005 problem.

i got a 05 MTX with a Lorenzo 60mm using a Mangum intake manifold with all the working gadgets and i got no check engines.

then again... i am an SRT-DESIGN! so i have special powers! lol.

^^ I am going to shoot you with a wet trout.

I think some of the 03rt drivers tried tps mmod, reflash, both - nada for them. As for the 05 sxt problem, I wonder how much of this is this one particular tb, some sort of defect?

srt-design wrote:well i doubt it's a 2005 problem.

i got a 05 MTX with a Lorenzo 60mm using a Mangum intake manifold with all the working gadgets and i got no check engines.

then again... i am an SRT-DESIGN! so i have special powers! lol.

I actually thought of this recently. I had a nice discussion with a good fellow geek friend of mine and with kevin_GP. This is actually a quite simplistic issue. People really are not thinking about this to its fullest extent.

I think you should completely read the thread. 04-05 guys suffer from the 2074. This is also known as PTB or partial throttle boost. SRT guys suffer from this a great deal. Most SRT guys have a much easier fix as this also relates to their boost.

The error code itself speaks for itself.

P2074-Manifold Pressure/Throttle Position Correlation.

taken from the computing dictionary

In statistics, a measure of the strength of the relationship between two variables. It is used to predict the value of one variable given the value of the other.

In engine terms it goes like this. This is more of a theory than fact. The TPS and MAP are used to calculate various constant routines in the ECU to keep the car going. Remember the definition of correlation above. Are two variables are the TPS and MAP.

If you have a 60mm throttle body. The bigger throttle body will suck in more air. Because its bigger it will suck a greater amount of air while the plate is not as open as the stock one. The stock throttle body would have to be more open in order to get in as much air as the 60mm throttle body.

I may have even had it wrong in my original assumption. Rather than using a resistor to decrease the feedback voltage, we would have to increase the voltage in order to normalize the system.

kc2002acr wrote:^^ I am going to shoot you with a wet trout.

I think some of the 03rt drivers tried tps mmod, reflash, both - nada for them. As for the 05 sxt problem, I wonder how much of this is this one particular tb, some sort of defect?

I have only seen one person try a reflash and map clamp. Nobody has tried the tps resistor mod.

i have a question not to bring this thread back to life but has any one tried slotting the tps and advancing it to make the readings appear that the throttle is open a little bit? because you can't send the pcm more than 5 vlts as the tps works off of a 5vlt referance dosen't it. so the increase in voltage would make it though another code for the tps to probably. so sloting it would work right? this is just a suggestion.