Auto correct constantly makes me look like a fool.
That’ll be the last think I check Hyden once all the easy stuff is taken care of. I would assume there is no way to check without taking the inlet manifold off? Given the kms on the car, and the prospect of it having never been done (nobody in Australia seems to be that aware of the issue and Audi dealerships tend to fob it off as a non-issue) I want to do it anyway, just need the time and patience to DIY it as there isn’t anyone even remotely close to me that would have experience doing it.
Once I get to the stage where there is really only carbon clean left to do, I’ll try and get a before/after dyno run, as there is a dearth of information on just what sort of actual power-to-the-ground impact the CC will actually have.
Also, what is the likelihood of their being an exhaust restriction due to overheated or collapsed cats? In S-mode, the exhaust note goes quite raspy (not in a good way) at around 3500rpm. Doesn’t sound as deep as youtube vids I’ve seen, though these can be pretty off in how they sound in real life. I might try a pressure gauge in the O2 port just to rule it out as well.
I’ll do some more datalogging on Friday night and see how we compare to the pre-service logs at around the same IATs.
Well, after the service and another few 3-8k runs on a nice cool night, my times have dropped about half a second. Previous winter runs a few weeks ago preservice were 10.8s, and I’m getting between 10 - 10.3 after the service.
Car definitely feels like it’s pulling better, but judging form the times, there’s still quite a lot left on the table.
Re-ran the airbox flap test, and it’s still not actuating after freeing up the mech. As before, I think the solenoid has gone as there is no solenoid clicking when it cycles that output.
The only other odd thing is it looks like the timing retard is even more aggressive after the service despite the better acceleration data. MAF also looks to be lower after service even though the times are better.
Link to updated post-service run: https://www.dropbox.com/s/cqo4h1j7imhd21g/WintervsSummerLogs.xlsx
Just another update, local dealer wanted $280 for the solenoid, so I politely said no. JHM have shipped me one and hopefully it’ll be winging its way across the pacific as we speak.
$280 that’s a big hit for that piece. It’s always nice to have a big part bin at JHM. Getting that intake working properly should help performance.
Like all things in Aus CV. I bet I get this solenoid twice as fast as the local dealer would take to get it in as well!
I try to only source performance related products from the states these days. Customer service is a different world compared to Australia.
I’ll definitely be looking forward to fixing up these little maintenance issues and getting the car back to within the ballpark of where it should be stock. Once done, next on the list is the intake spacers (our latitude is closer to the equator than florida over there!) and exhaust system.
After that, just waiting for the R&D to finish on the JHM stage 2 
Just an update. Replaced the airbox flap solenoid yesterday - man, what a PITA to get to. Gave the flap mechanism a damn good lube and clean and the new solenoid pulsed it perfectly during the output tests.
Butt dyno on the way home confirmed a significant increase in acceleration past 5k, which was to be expected now that it can breathe properly.
Hoping to get some time tonight to run some more logs to see if the 3-8k runs are getting back down towards where they should be.
Looks like I’m back to the drawing board. Update log from tonight here: https://www.dropbox.com/s/cqo4h1j7imhd21g/WintervsSummerLogs.xlsx
Times show about the same as before the airbox solenoid was fixed. There was likely a lot more heat soak on these runs tonight though, so I’ll need to check again with the engine cooler to see if there is much change.
Didn’t feel like as much of a kick after 5k like it did yesterday when I gave it a quick squirt after fixing the airbox flap solenoid.
Not really any gain in MAF air flow either which is strange considering it should be breathing much better from 5k now that the tertiary inlet in the airbox is opening. Might have to run the vacuum test again and make sure the flapper hasn’t stuck closed. Was actuating perfeclty yesterday though.
I’m seriously thinking of moving my Aquamist off the Evo and onto the RS4 to see what, if any, difference it’ll make to the timing retardation. Looks to be around 4 degrees average timing difference at 6k across 4 cylinders between this run and my Winter run where the temp was about 10 degrees cooler. Ambient as indicated on the dash on this latest run was 24deg celcius.
I had another thought too, has anybody done any testing with a variable pot on the IAT sensor to see how the engine responds to a cooler “read” charge temp? Is there a measuring block for the knock sensor output? Might be interesting to graph the timing retardation against indicated IAT with the same ambient conditions, to see just how much timing correction the stock ECU makes based off IAT readings.
Car might just need a damn good carbon clean too lol, though I’m yet to be convinced in all my reading that it’d make that much difference, but I’m running out of things to rule out.
I’d suggest doing a bit more reading on carbon. It has shown to have various levels of impact on acceleration performance. It effects each car differently as no one car has the same level of buildup. Checking and cleaning would’ve been the first thing I’d do. Also temperature wise. Our acceleration is also greatly impacted by temperature. You’ll notice all of the FSI cars report logged timing pull in hotter weather
I just had my car carbon cleaned aout 2 weeks ago. iv read that carbon can rob you of up to 80hp but I personally don’t believe that. I would say 20 or so. the difference is noticeable on the butt dyno but not the day and night differences some ppl describe.
It’d have to be a pretty big power difference to go from 10 second 3k - 8k run to 8.5 second.
I still think the pulled timing has a lot to do with the difference in performance. I’d love to get my hands on some more VAGCOM logs from other people with different ambient conditions. Does anyone know or have a few they could share? I could be just chasing my tail, and 10s 3-8k is perfectly normal for 24deg C ambient temps at sea level.
I think high ambient temps are a key issue for pull timing. That is why i am skeptical in buying anything than a custom tune. I have been contemplating the JHM tune but i am not comfortable as to how this takes into consideration large variations of intake temp and humidity between summer and winter.
JHM says this is done automatically ( guess by some fuzzy logic in the ECU) but i know the eCU takes care of small variations and not big ones.
Perhaps countvohn can chip in to this.
And be careful about the really high timing pull…as it can cause serious damage.
Here in Ontario, our temps go from +30 in the Summer and -30 in the winter (deg C). Summers are humid betty swollocks. We’re lucky to have had a few modded Audis in our little gang - JHM tuned S4, JHM supercharged S4, JHM tuned RS4 and APR B8 K04 A4. I can’t recall anyone having any issues in any weather, other than the supercharged guy probably needs an intercooler in the summer lol. Certainly the JHM and APR tunes adjust accordingly with our big variations in weather.
Also, CV lives down the road from us and has similar weather. A lot of the testing has been been done in these extremes. Which reminds me, CV should join us at Cayuga one of these days!
What kinds of temperature readings are you looking at where you’re located? I see what’s considered extreme temperature both on the hot and cold scales. I’ve never had an issue with my jhm tune.
Firstly allow me to say I am no expert. My limited knowledge, tells me that N/A cars favor cold weather. Secondly the problem may arise from big differences among days.
One day at 30-35C nd the next at 20 Celcius.
I don’t have the JHM tune but if you guys say that it is fine, then I guess personal experience always beats down on theory!
Ok, I just did another couple of runs at 6am in the morning (damn I’m keen to do this on a Sunday lol). This time I only let the car get up to running temperature (75DegC oil temp) before doing the runs to eliminate heatsoak. Ambient temp was 15DegC compared to the 22DegC of the last run after fixing the airbox flap. I’ve added the info in the same URL/spreadsheet as an additional worksheet.
https://www.dropbox.com/s/cqo4h1j7imhd21g/WintervsSummerLogs.xlsx
Interesting notes.
- 3k-8k runs are down to 9.7s
- Average timing pulled at 6k rpm is about 1 to 2 degrees less
- Still a lot of timing being pulled, even with no heatsoak and good ambient conditions
From this, I am happy that the car is at least now pretty close to where it should be for its age. I think at this stage a damn good carbon clean should get it back down into the 8’s. Carbon build-up may also be responsible for the higher than average level of timing pull even under perfect conditions. All runs were done using 98 RON fuel (please note that AUS uses different octane rating system to the US, our 98 RON is equivalent to your 93 AKI), though I might try a bottle of octane boost just to see if it makes any difference at all to the timing retardation.
A JHM tune is also on the cards once I get the exhaust done, but I wanted to make sure that the car was baselining correctly before starting the modification path. I now have good history of logs to use going forward to gauge performance increases in the future.
Also, interesting to compare Toronto weather to Townsville. Toronto average temp for summer is 19DegC and 82% relative humidity. Townsville is 27DegC and 84% relative humidity.
Damn I went to Townsville once to do the Yongala wreck dive. Got shitfaced the night before and spent the day on the boat puking
Nick feel free to start a new thread. This will allow the many members that have the JHM tune to help let you know their temperatures and the results. It’s not uncommon to have temps of 48deg in the morning and close to 100deg by mid day. The JHM tune has been testing all over, if for some reason your location would require an adjustment that can be done. Still know that the JHM RS4 tune is on cars from Australia to Asia. We have worked very hard to see almost every climate you can experience.
Caillin, Carbon holds in heat. Good maintenance should always start with a carbon clean. It’s very unlikely that you will ever see no timing pull. There are so many variables on why the car corrects, you would have to address each one individually. The best way to eliminate that is to do a good carbon clean.
It’s probably also worth mentioning for those that are unfamiliar with flash tuning in general, that you still have all the same failsafe parameters and tuning adjustability in place from the factory ECU when you go with something like the JHM tune that you do CV. So it can adjust based on pressure, inlet air temp, coolant temp etc just like the factory ECU. I get the feeling some owners think a reflashed ECU is something that replaces all the factory system without the same capabilities. I know that’s a “no dur” comment for most on this forum, but based on Nicks comment, might not be universal knowledge.