Hi chaps, After the poor showing on the dyno last week, (which admittedly looks to be mainly down to the dyno itself not handling DSG properly) I decided I should do some checking to make sure everything is actually running as it should. Funnily enough, while driving back from town before I made a start, I began to get massive hesitation when accelerating, mostly from about 1500rpm upto about 3000rpm. For example, I went to go past someone on a dual carriageway and put my foot down, in the correct gear, and nothing happened, the revs started to go up, but no power at all, then thump, in came the power. Hesitation only at lower rpm. So I fired up VCDS when I got home, no fault codes logged, but created some logs on blocks 002, 015 and 016. Which should give MAF readings and also misfire readings for all 6 cylinders. Please see pics below. So as you can see, I have intermittent misfire on cylinder 5 it looks like. I'm assuming main culprit tends to be coilpack? I am going to change plugs soon in addition to this. Also I have a question about the Misfire Recognition column, am I correct in saying that this should always read 'Disabled' if your engine is running correctly and not misfiring? Mine keeps flicking between Enabled and Disabled. The 2nd thing to note is the MAF readings. The most I could get out of it was 202g/s and 192g/s. What should be a good g/s reading with WOT for a V6? (I had my foot to the floor, but engine load appears to only say 90/95% or so) From a few searches it appears to be too low a reading, when trying to calculate a rough bhp figure by multiplying by 1.2. So from this, does it look like I have a possible coil pack failure and also a duff MAF? Or are the MAF readings hampered by the misfire? In which case do I sort out the misfire first then retest the MAF?
There was a thread on here previously about the misfire detection and IIRC there was no ryme or reason if it's enabled or disabled, and from what I remember no easy way of enabling or disabling it. Think benthejettaman started the thread. Here we go - http://www.clubgti.com/showthread.php?265226-turning-on-missfire-detection&highlight=detection Misfires are usually coil packs on these. Don't ignore plugs. I can't get the old logs from the R32 as on an old dead laptop but may be an old thread about my findings? Found it - R32 with Schrick 264 cams, Revo 215 g/s http://www.clubgti.com/showthread.p...-calculating-bhp-from-MAF-readings&highlight= The thing is usually you need the g/s reading to raise as if you're looking at a power trace on a dyno print, will drop off after peak power, yours seems to drop out a bit at high revs before peak power. BUT I guess it's changed up a gear during the logging run? Goes up to 6k ish, then back down and up again, so that's probably why! Stoopid gearbox! lol Really needs to be done in one gear only, but not poss on your DSG.. Usually the test is to disconnect MAF and see if performance improves on a bad MAF, but it may put faults in (which you can clear anyway) I get 202 g/s divided by 0.8 at 252hp So not too far out surely?
Thanks for the info Gary, much appreciated mate Had a read through those threads you linked, I think the column with misfire detection enabled/disabled is load dependant, since it seems to come on and go off depending on whether I'm on throttle or not (had a quick glance at laptop as I was driving) - confusingly I read in another thread that it should always be off and will only show enabled when a misfire has been detected.. but that doesn't tally up to me as the cylinder columns don't always show a misfire. You're correct - I couldn't take it to the red line cos the damn DSG box wont allow me to! So my logs will show it dipping before rising again as the gear changed. I did those logs going up a hill, so will give it another go on a flat, long runway and see what sort of readings I get. 252hp doesn't sound too bad, that is 5hp over standard on the BHE V6, just surprised as many quote the Revo map as giving 12hp+ in addition to more torque and a smoothing of the torque profile when the inlet manifold goes through the changeover phase. Just another reason to never trust re-mappers quoted figures! I really am contemplating a remap of the DSG, I like the idea of more control in certain situations such as above. Tomorrow I'm going to log some more while the engine is cold as I've heard misfires are more prominent, especially when logging, from cold. (No red line madness though ) Regarding the misfire on cylinder 5, is that a pretty cut and dried case do you think? If so I'll get ordering on a new coilpack and a set of spark plugs. In summary, it appears MAF is ok, but possible misfire..?
Swap coil pack from #5 to #6 do your test again, see if it changes the misfire to #6. As ever with a generic map it's very much individual car dependent, pinch of salt required! Dyno lottery too!! Also the Revo has settings for timing/fuel and throttle response that can be changed with the Revo 'SPS' switch, I think if battery has been disconnected the settings need to be redone.
I had the battery disconnected a short while ago, mostly I just wanted an ECU adaptation reset as I removed the TB for a clean and reset - could it really have wiped the Revo map?! Surely they wouldn't design a map so that everytime you disconnect the battery you have to get it reflashed, that sounds like madness! I will get on the blower to them about it and check. A google search gives conflicting info on this.. The misfire only logged for a bit of my journey yesterday so I'll do the coil pack swap on a cold engine to give the most chance of spotting a misfire! **EDIT** Found a good thread regarding the Revo settings resetting to 'stock Revo' after a battery disconnect - it appears that this only happens on MED9 ECUs, most of the mk1 TTs are ME7, in which case disconnecting the battery is fine.. Revo thread
Hmm, logged the misfire blocks from cold this morning and not even a hint of a misfire Something must be on it's way out but not quite gone yet then.. the most annoying stage as it makes it hard to diagnose. I'm going to whip the coilpacks and spark plugs off of cylinder 5 and 6 and compare notes, see if spark plug colour is off or not.
Ok these spark plugs were apparently replaced about 18000 miles ago.. they look like they've been in there for the entire time Are they OEM spark plugs? They don't look like the recommended NGK 7563 Iridium plugs which should last 40k miles, so I reckon I will change those first and monitor the situation.
i would still pop down to your local revo dealer and get it checked out, unfortunatly they do suffer from from the maps going to back to basic settings when the battery is disconnected, unfortunatly this is a downside to having a generic map that has the options of being fine tuned most revo dealers should be able to do this for free as it is a 5 min job
The Revo map was done at the TT shop, so they aren't far from me, I may nip in and have them take a quick look. Regarding the spark plugs - should they be that corroded? I've never seen that kind of corrosion on a car that has supposedly been serviced regularly before. Is this caused by coil pack not sealing properly or something else?!
aye water get's down and has no way of getting out heat of the engine drys it up over time the early coilpacks suffered due to this as they rust and break off yours look like the new type
Just got back from being away with work all week and decided to log my 40min drive home on VCDS - didn't get any misfires on cylinder 5, but got single events about 90 times (90 cells on spreadsheet) on both cylinder 3 and 4.. Sooo, I'm really hoping these new spark plugs sort it out and that it isn't the coil packs - 6 new ones will be expensive!
Changed the spark plugs today for the recommended NGK ones - 6 for about 48 on ebay! Took her out for a spin afterwards and ran the misfire blocks again plus the MAF block while logging - got some pleasing results Highest reading during a 4th gear run from 30mph upto auto gear change up in Manual mode resulted in 214.25!! 214.25 / 0.8 = 267.8bhp! That's more like it! Here is the p/n and details of the coil packs (all 6 were the same) Does anyone know if these are a known good coil pack or are part of the recall? I rang Audi today and they took my details and will get back to me on Monday regarding the recall.
Car has been left for a week as I've been away for work - started up, drove part way home and started to get MASSIVE hesitation at low rpm when putting my foot down. As it got to about 3krpm and above it suddenly seems to pick up and off it goes. It is like it is severely holding back or like the clutch is slipping and then engaging and off it shoots. The engine note does sound different when it does this. It did it nearly all the way home, whenever I tried to accelerate. Halfway I stopped and unplugged the MAF to rule it out of the equation. Had exactly the same issue with it disconnected, so MAF is good. Have been in contact with Audi regarding coilpack recall and apparently mine were replaced 07/2012 - so is not due for recall anymore. I logged the engine misfire blocks all the way home via VCDS and when I looked through the spreadsheet afterwards there is virtually nothing in there that would indicate as big a misfire/hesitation as I am feeling. A few of the cylinders logged single sets of misfires at different times but nothing that even set off any engine fault codes. This is getting really frustrating. I don't understand how something so pronounced and evident can not log a fault code. Should my 'recalled' coil packs have gone faulty already?! If so, that is just ridiculous. Can anyone help with diagnosing what may be the issue - are there any other tests I can do to determine the issue?!
Log the fuelling to see what the injectors are doing. They go on mk5 gti's, so it could be the same on these
Do you know which blocks are for the injectors in VCDS? I only have VCDS lite, so not sure if it will even give me an option to do this..
I think each engine is different. Try on the Apr website. They have the blocks listed for the mk5 golf. They might work.
Sent this to GVK - who has very kindly been PMing me to help me with my issue, but thought I would post this here in case anyone else is having a similar issue. I am veering towards something else that I think is the issue - the vacuum control for the intake torque port switchover thingy. Not really sure what to call it! It is controlled by a little vacuum unit on the right hand side - I think this is either getting stuck or possibly I have a vacuum leak. Used the car today and not had a problem since I 'unstuck it' a little by pushing it down a few times. This would also go some way to explaining why it has no power until it comes alive at the 4krpm (ish) mark, which I think is where it changes over isn't it? So I think I am going to try and trace the vacuum lines and check they are all kosher and then turn my attention to the vacuum unit itself and maybe get a new one. *EDIT* I've thought of a very simple way to test if this is the issue - just disconnect the plunger from the white ball socket and take it out for a test drive and see if I experience the flat hesitation that I've had before - shall try it tomorrow! Found this excellent thread on R32OC - in particular the post about halfway down from Andy4motion; changeover valve not working
Did you manage to resolve your issue? I've changed the intake changeover solenoid and one way valve according to Andy's thread and it's helped but I still get hesitation and rich running. Want to get it running better before getting it mapped. Think I need to log the blocks you have to check for misfires and also injectors.
