Oh, I see you’re using generic OBD2 mode for some reason. Don’t do that because you won’t get access to most of the data you can read from these cars with VCDS.
Yeah sometimes it’s faster to just open the generic mode if all I want to see is the fuel trims and misfires. I don’t know too much about using VCDS but I’m figuring it out quickly.
I cleared codes last night so we will see I’d anything pops back up the next time I scan it. I’m going to order the intake spacers maybe today. That way I can do the intake gaskets while I’m at it. I’m debating on ordering the check valve kit and redoing the valley pan gasket since I’m in there. It’s not leaking…but if you have to remove the gasket you might as well replace it right?
Take your time when you bolt down the intake. The spacers really help in the hotter weather.
As for the check valve. They dont fail that often . You can pull your oil filter housing and if you have standing oil at the base of the filter your check valve is good. It saves you a ton of time and money by just checking that way.
i should have thought about that! good info-- thank you Justin (that is your name right?) I’ve been looking around and didn’t know you had as much experience as you do… example… just ran across an old audizine post that you had done the timing adjusters in the S4 platform 17 times without pulling the engine. Props to you man!
The only reason why i would do the oil check valves is because of the start-up rattle. It doesn’t do it all the time, but i have heard 2 distinctively different start up rattles (once or twice on a hot start—yikes 
so obviously i need to address the intake leak…but what else could cause the s4 engines to run rich? i know that the spec is ± 10%… but you want to be as close to 0% as possible (with small fluctuations) being at -10% (to me at least) isn’t acceptable as being normal.+ or - 5 %…yeah i can see that, but idling and the short term fuel trims hovering from -8 to -15 % just isn’t right
Thanks for the kind words. I might have done a few things car wise. I enjoy helping thats why I find a nice home here.
As for the check valve. I didnt want to burst anyones bubble but that wont fix cold start issues. It was something people wanted to believe to convince themselves that they didnt need to do the timing components on the back of the motor. Sure the check valve can get stuck open if you have some debrits in the oil but all you have to do is to unfreeze the plunger and your back to good. Its not bad to replace it if your doing a full timing job but to replace it due to rattle its already too late. You have a more serious issue. Its just how bad is the issue causeing the rattle.
As for the rich condition. That can happen if you have blocked cats. An intake leak a throttle body leak a PCV issue or an injector issue.
the instant fuel trims are going to jump all over so dont get too stuck on that. Those can be effected by the weather and altitude. Its the LTFT you want to look at.
Also try pulling and cleaning the 02s if they are not new.
Awesome. Thanks! It just drives me nuts when my car doesn’t run correctly. It acts like it is misfiring at idle. I’m assuming that’s because of the intake leak. I want to do the timing components. Saving now for them. I’m debating on how far I want to go on this platform. My car doesn’t consume any oil so I’m assuming there is no scoring on the cylinder walls (can’t truly assume anything). I’m debating swapping in a sleeved block and going with a supercharger… or just going to a different platform.
Honestly once you do the timing stuff your really in a good spot. Not much goes wrong with the motors unless its timing related or you get a piston scoring the walls. If you have no oil consumption thats a great shape motor. Do a commpression test to make sure everything is as it seems and you should be good for a long time.
At that point getting the blower is a great idea you can save for a built block and at that point your makeing super car power and acceleration with the stage 2 JHM blower kit
Well i can honestly say that there is something up with my car. I’m pretty sure there is something either wrong or going out in the fuel pump. I caught the fuel pump making some weird noises. banging (yes it sounded like someone banging on the rear quarter panel and i had to get out to make sure i wasn’t going to run someone over if i drove off from my parking spot at home. very loud and noticeable, and happened multiple times) and then it makes this shuddering sound. i actually caught this on video. This happened when i put the key in the ignition after it had been sitting for like 10 minutes:
http://i1098.photobucket.com/albums/g361/sq5hunter/th_20160424_130123_zpsgikajyhc.mp4
what had happened, was i went to start my car and i heard this noise. it was loud enough that my neighbor heard it in her garage and she asked me about it. i turned the key off and let it sit for about 5 or 10 more minutes and when i had her put the key in the ignition and turn it on, i caught it on video. i’m guessing there is some sort of check valve in it that could be going bad? would this be in the pump of the filter?
that being said, my car’s power has returned and i don’t hate my car any more. (at least as long as i don’t have to change the fuel pump lol) odd how the car cut (in my opinion) at least 50 to 100 hp for that time. it pulls twice as hard now. i wonder if this was due to some bad gas. i went somewhere i don’t normally go and i wonder if he put regular in it and it caused the ecu to pull timing? or am i just reaching at straws?
Ill try to listen again today. The last two times I tried to listen I didnt get a video with any noise. Was it just that one day
I’m uploading the video to youtube. Maybe it will sound better. It has done this multiple times. Today it did the rough idle and knocking noise when I came to a stop after a 50 mile drive on the freeway.
If you need better resolution and the ability to select specific variables, then download VisualME7 Logger from NefMoto. It’s what i use for catching hiccups. I run my logs at 30samples/sec currently (and could go faster) and log 24 individual items/variables (and could select more)
ok try this.pull up the carpet and pull out the cover for the fuel pump and sending unit. From there try the same test again. It sounds like the car is starving for fuel and something is moving around. Almost like there is a pump that is loose in the tank or something like that. It might make sense to peek in the tank and see what comes up.
Also from what your saying performance wise there is a chance the pick up or fuel pressure is effecting performance.
Thanks guys. i really appreciate all your help. what ill do is download that logging program and see what comes up. i suspect fuel pressure to be part of my problem. Someone oer fn anothorum mentioned for me to change my fuel filter. It is only a few months old, but i absolutely understand that could be the case. Are there any aftermarket fuel pumps that will be sufficient for stock and future upgrades that are drop in? I’ve looked at a few, but ive never retrofit one to a car. I took my old Silvia’s fuel pump out, soldered a level sensor to it and reinstalled and it worked great. One thing i know about my s4–i ran out of gas right after getting it because the dash said i still had like 15 miles left. it was wrong. yay for more parts.
Ok, so after i download that program… can i pull up the fuel pressure (or can i do this through VCDS) and see if my car is starving for fuel under throttle? I’ve always wanted to be able to look at stuff like this and maybe even start tuning my own ECU, but i know nothing of the sort…
First off I wouldnt waste the time downloading another program if you already have vag com. The turbo mode in vag com in VCDS is faster then you would ever need and you can look at 50 things in VCDS and even in vag com you can log on block and see everything you need to see at the resolution you need.
Everything you need to do plus some can be looked at in VCDS. Not only that but your in my opinion not even at that step yet. You are not going to find the solution looking at a computer screen. Your going to need to pull off the parts and look to see whats going on with the knocking and other issues first.