bmw 645ci, problem at low speed and poor light throttle response

Hello friends!
I am pretty new to this forum!
first off all, would like to say that you guys are awesome! I've learned a looot of things from you all! Thank you !
to my problem! I have a bmw 645ci 2004, 110K on it. It is my first BMW. Never had so much problem with a car. my indy and I are tired of seeing eachother lol Anyway, I got 2 problems :

First problem: the car had rough idle, (not when cold) actually mostly when car was warmed up. It happened at idle in D, N and P.

2. problem is: it feels like there is a gap/play in drive shaft somewhere ! you feel it specially when you going downhill at very slow speed/ RPM in 1st gear, the car is rolling forward and you lightly step on gas. then you feel like kick and a clunk/clicking noise under the car!
The indy said these two problems might be related. He said the rough idle might cause poor throttle body at low speed and the kick! The only code we got at that time was the intake manifold sensor. Replaced it along with intake manifold gasket ! got car smoked and fixed all the vaccum leaks. car kept having the problem still. The indy started replacing stuff :

New fuel filter
new fuel pump
mass air flow sensor
fuel injector service( twice)
reprogramming
he checked the alternator and found its bad. so got new altenator.
he also raised the RMP by 50. It was at 500 before, now its at 550.
BTW, the flex disc/ juibo was replaced 10k ago along with engine and transmission mount before I got this problem. I just replaced those as maintenance. I did not have any problem before that!at that time i did not have this problem . Also, transmission was replaced under warranty like 28k ago!
Now, the RPM problem is solved. No rough idel or jumping RPM! But, I still have the other problem at low speed. indy lifted the car, moved the drive shaft with his hand, checked the juibo, drive shaft and tranmission mounts and said they are ok.. he said its probably because of the poor throttle response at low RPM and not the drive shaft of juibo! we checked the codes today again, and the car still gets the intake manifold sensor code he has no clue why we still get the code! He checked the battery it was at 50% charged and said it needs to be replaced!
My question is:
1. why do we still get the intake manifold sensor error! Can this cause the problem at low speed/RPM ? can the low battery cause this? (I dont have any starting issuse!)
2. Could the indy have done something wrong and damage something while replacing guibo, transmission and engine mounts? Is it possible to damage the transmission output drive while replacing the guibo?
3. coils have been never replaced before. original from 2004! Indy said it might make your car runs smoother at low RPM and improve the throttle reponse ! Should I replace those too?
4. Can the problem be because of the trottle response or driveshaft?
BTW, at that time when replacing the juibo, he also clean the trottle body valve and reprogrammed the car. Unfortunately, the programming crushed and the computer could not find any module of the car! he called an other guy, he came with some other equipments and reprogram the car again!
5. is it possible that the trottle body valve was damaged while cleaning and know it doesnt work well at low RPM? or maybe the DME is not working well ?


I really realllyyyy appreciate your help!
Thank you in advance!
Ps. Sorry for my bad English. I just moved from europe!

Cam Sensor my bet, plus I don't think you would get a cel from it , but don't get the BMW ones just get good euro ones 50.00 each

Thanks What does cam sensor do?! What's would be the symptoms!? I asked the Indy guy once and he said most likely you will get stalling problem when it fails!i don't have any starting or stalling problem! Btw, How many cam sensor do I need?!
Thanks

Will cause ruff idle , loss of power, delayed acceleration , etc . Only when it fails will you get stalls , no start , one for each cam , just eBay them, as a test unplug them and see if their is crap and oil/ dirt in side the plug clean them brake clean will. and replug the harnest, and test drive see if its better

The symptoms are kinda similar to my problem! Where are they located?! Can I do it by myself ??
Thanks

Yup easy @ the ends of the cam shafts one bolt and slide out put new one in, eBay to get pic of them kinda like a lipstick with a side shelf on it for the bolt

Just use the search for the location pic but u can't miss it

Btw, can the cam sensor go bad without throwing any code?! Is cam sensor the same as crankshaft position sensor ?

O ok thanks! I'm gonna test the sensor and let u know ! Please let me know If you think something else would also cause the problem! Thanks

Don't think so , but just oil in the connector will make it act up , so just clean the connectors first

This pic should help print it off the vanos sencers my be leaking too but $$$$ 90% sure it's the cams

Wrong pic

Hear ya go

Intake has its own sencer as well , it changes the air flo path to be direct or funnelled in the intake runners

Pic

Thank you soooooo much!
I am gonna replace both camshafts ( there are 2 camshafts for N62, right ? ) and you said It doesnt need to be the factory from the dealer! I found some OEM ones in ebay for 55 dollars! That would work, right?

Yup easy , 4 cams 32 valves 4 valves per cyl, let me make sure it's only 2, I am a master tech , but new to bmws , but the system is used by lots makers

2 per head exhaust / intake , but same part# if you look at the pic you will see it directs you to 2 of them with the lines showing hear and hear, but many times just cleaning the plugs works but its only 200 for 4 so cheap, and you can easily DIY

I hate the stealers (dealers) I was told on a daily basis to up sell ! Even if it did not need it, every shop is the same + /-

Thank you! I'm gonna replace all 4 camshafts along with coils( never replaced from 2004) and see what happens! Hope it will solve the problem ! The car is not fun to drive anymore ill keep u updated!

So, I took my car to the shop today! we checked the battery and this time it was at 81%. Does it mean the battery is good?! the battery is a "Duralast" from autozone .Is it a good battery or I should get a BMW factory battery in? also, we replaced all coils . The coils looked really bad! some of them were loose and came out easily! After replacing the coils, the car run much better overall, but I still have the low speed hesitation and poor light throttle response so What do you think it would be the next step ? Camshafts?
Is it possible to have a bad camshaft without throwing any code? I was trying to convince the mechanic today to take them out and clean them but he said if there any problem with camshaft then if would threw the code !! I dont know!! should I replace them regardless?
should I replace the battery with a BMW factory one? or trying to reprogram the whole car again?!
Btw, I cleaned the throttle body valve once before ! Do you think It might be damaged and cause the poor light throttle response?
Thanks again

Camshaft sensors not the actual camshaft the camshaft would be a huge job just the sensors to clean them and or replace them

Oh batt is good above 70 % is great . Lots of systems running in the back ground . Even when car is off

Thanks! I meant the sensor too ok, I'm gonna clean or replace the camshafts and see what happens!ill keep u updated!btw, Is there anything else beside camshaft you think we should check?!

Can't change the cams, only the cam sensors , easy job , to replace the cams it's a full day of work and nothing will be different