03 C32 throttle problem after intercooler replacement
 

Hello everyone, first i would like to add that over the years this forum has silently helped me many times in diagnosing the cause of the minor problems i encountered with my cars.
So, the back story..The problem i am running into now is regarding idle oscillating, as soon as i barely touch the throttle pedal. The car starts up fine and idles fine for about 5 minutes after start but after about 5 minutes it almost feels like i have a misfire and the whole car starts the shake kinda like as if my motor mounts have gone bad (Motor mounts are 5k miles old and genuine part). If i press the throttle pedal so that the rpm's go up to 2k upon releasing the pedal the car remains at 2k rpm. I searched through out the forum for an answer to this problem and it points towards the throttle pedal itself or the throttle body or replacement of the engine harness. I do not want to start buying parts as these add up really quickly $$$. I have attached some pictures of all the work performed on the vehicle over the past couple weeks. Modifications include addition of oil catch can from Needswings as well as inter cooler fluid isolation kit also from Needswings. I do not believe these modification are causing the problem i am experiencing.
A day before i had planned this repair i had an error P0210 but no ESP or check engine. Very sluggish acceleration when this happened but upon restarting the car it was fine again.

Just verifying if the vacuum lines are in the right places..
 

I have a few pictures of the front of the engine EGR valves and the vacuum lines that go to it. I am not sure if i have them in the right slots. Can someone confirm their placement? I am able to slide the vacuum lines which tells me that they are not getting pitched anywhere

Also the last two pictures are from the SDS system, the first one is before i press the throttle pedal and the second one is with the throttle pedal depressed as the instructions say to the kickdown. Note the values on the potentiometer for the throttle body are not in range( in second pic, i have also reset the ecu before performing the test but no difference. Does this mean the TB is said goodbye to me?

Thanks in advance to anyone and everyone who is able to help.

seeing how you just replaced the I/C I'd say you either forgot to connect something or there's a vac leak.

Change fuel filter, and gas pedal in car both cheap and easy, or it could be throttle body, what did u use to wrap IC (backed patatoe)

All the vacuum lines are connected. I have been looking around for any leaks in the vacuum system and it all seems to be working:nix:

Since the car starts up fine and holds up the revs at 2k I do not think fuel filter is the problem. The voltage readings from the throttle pedal are within the allowed parameters on SDS so not sure that is the problem but I am not completely ruling out the throttle pedal. I think it's either the throttle body or as you mention the pedal itself.
I am going to start with throttle body since I picked one up yesterday from the junkyard.

The product I used to wrap the intercooler is called Thermo-tec heat barrier.

If it's just like the 55k motor its happened a bunch of times where people mix up the throttle body connector with the bypass flap throttle body connector. The connectors are the same and it's easy to do.

Vaccum lines are hard to diagnose cause they usually disintegrate from inside out cause of the oil. Gas peddle is easy to change. What codes came up? Nice wrapping on IC

Rocman8 - There is only one connector and that is the one which connects to the TB actuator.

Morphh - So, at the moment there are no codes present. The used throttle actuator is giving same results, Oscillating rpm's after start. If the throttle pedal is the culprit would it give correct voltage values and position when i test it in SDS?
I think i am going to run the same tests on the 55 and see it there are any changes in the voltage and position values before i dismantle the whole thing and start from scratch...again

So, it turns out the Oil catch can was causing the oscillation in the engine speed, i put the configuration to its original settings and no more idle, rpm bouncing issues. I looked over and over to make sure i have installed the pluming according to the manufacture's notes but to no avail. For now, its working well without the catch can mod so i am satisfied. Thanks to all the people who contributed to helping me sort this issue.

U have needswing oil catch can? That was causing the issue? I bet one the hoses have crack or hole in it, so it was a vacuum issue

Yes, it is the Needswings catch can. It was a vacuum issue. I am going to take it out of the car this weekend to inspect the hoses and go from there..