Audi Coupe 2ltr 16v (ACE) 1993 - Pinking?

Posted: Wed Jul 21, 2010 1:21 pm

Hi folks,

I think my car is pinking. Pulling away, in 1st, between 1-2k rpm, I hear what can best be described as the sound a tyres makes when you've got a stone stuck it in, a kind of metallic tapping sound, once past 2k its goes. If I'm rolling along in 2nd, again same rpm range, same sound.

The other end of the scale, when accelerating 3k and upwards I tend to hear what sounds like the exhaust knocking.

Do these symptoms sound like pinking? If so, according to the forum its probably a timing issue? I'm hoping to get my new cam belt fitted either this week or next depending on the garages work load. If it is a timing issue, I assume the belt change should fix this and therefore I'm best not touching anything?

Thanks in advance

Rog

Posted: Wed Jul 21, 2010 2:17 pm

usually if timing is out, they don't run...

Pinking- try a fuel additive, see if it "cures" the issue. The fact you get a sound like the exhaust knocking suggests not, though. Have you checked the hangers on the exhaust? It could be knocking, the "pinking" sound could be a heat shield resonating?

Just a thought.

If pinking, I would expect the engine management to retard the ignition to cope, so you could potentially have a slightly dodgy sensor?

Posted: Wed Jul 21, 2010 2:33 pm

Pretty sure its not he exhaust as I wondered that to start with, so got out and gave the exhaust a good shake. Maybe a better description of the noise is to say its a bit like when you're in to higher gear, but I'm not, it happens as the revs get higher and I'm pushing the engine to go faster, rather than letting off and it dropping down too low. My engine also runs on, so when I turn it off, most of the time the engine continues to run and kind of stall itself after a second to so. To try and cure the running on I switched to super unleaded, and the first 3 or 4 stops the engine shut off properly, but now its running on again.

Thanks for any help

Rog

Posted: Wed Jul 21, 2010 2:40 pm

considering additional info (run on) it's worth getting the codes read, I think....

Posted: Wed Jul 21, 2010 3:44 pm

How do you get the codes out? Do I have to take it to a garage, something I loathe to do, or can I buy a gadget to read them myself? I'd sooner spend £100 on a gadget than £50 in a garage for that sort of thing, at least once I own something I can use it again and again as necessary. I have looked into it a bit, but all this Audi stuff is foreign to me at the moment, anyway I was reading about a DIY code reader below is this any use to me?

http://www.20v.org/tools.htm

Thanks again for the help.

Rog

Posted: Wed Jul 21, 2010 6:26 pm

You can try setting the timing with the distributor, but if the pinking persists, you may need to try re-seating the knock sensors, or replacing them if that doesn't help.
The thing that finally fixed the pinking in my engine was replacing the cam-chain - a worn chain makes the inlet cam lag behind the rest of the engine, meaning that ignition occurs before the inlet valves are fully closed.

In fact, if your cam-chain has more than about 120k miles on it, I'd probably change it first, as it will probably be worn enough to cause pinking.

Posted: Wed Jul 21, 2010 9:46 pm

How hard is it to change the chain?
I know you've had your engine out before now,is that when it was done?

Posted: Wed Jul 21, 2010 10:02 pm

Ironically, I didn't change it when I had the engine out, but that's good for anyone doing it as a stand-alone task, because I did a write-up when I did get around to it last year:

http://www.audifans.net/ftopic-28138-0-days0-orderasc-chain.html

Posted: Wed Jul 21, 2010 11:23 pm

I reckon our 16v is well up for this job as it pinks like you wouldn't believe and having covered 210,000+ miles it looks most likely.
I am pretty competent at many jobs on cars but a little nervy on "major" engine work,it took me months to pluck up the courage to get the gearbox out and change the clutch!
I've never done a cambelt on any car and would love to get one out of the way,so quite possibly this could be the excuse,i'm just a bit put off with the whole cam alignment/ TDC thingy! what specialist tools do you need?

Posted: Thu Jul 22, 2010 5:45 am

Type17 - You mention re-seating the Knock sensors, do you mean the 2 connectors up top in the engine bay, or follow the cables down to the knock sensors and do something down there?

I'm not up to robonmac's level, gearboxes and clutches, although its on my to do list for my Mk1 8v GTI. I did change the cam belt on the GTI once whilst following a guide to clean the Tappets, it was all easy enough, but I didn't have a strobe light, so to get the timing roughly right, I put a screwdriver down the no1 spark plug chamber and turned the engine over by hand until it was at the top. Anyway, the 8v GTI engine (DX) is a non-interference engine, so you can't break anything, where as the ACE engine could all go horribly wrong, so I'm a bit more cautious.

As I mentioned up the top, I'm getting my cam belt changed next week by a friend in the trade, I did mention the chain, but he said its unlikely it needs doing, plus its quite a bit of extra work, but to be fair you guys know these engines inside out, so once I know the belts changed and the cars all timed up as it should be, I'll look into doing the chain myself. As I've got a bit of an oil leak on the rocker gasket, when I replace that I'll be at a good point to do the chain I reckon...

Here's the link to Type17's cam chain guide...

http://www.audifans.net/ftopict-28138-pinking.html

Any thoughts/advice on the code reading guys?

Thanks again

Rog

Posted: Thu Jul 22, 2010 7:11 am

look in the classifieds section- one of the guys was doing a group buy on a code reader for good money...

Posted: Thu Jul 22, 2010 6:35 pm

When I was considering how to get rid of the pinking, I was told that I might not need knock sensors - apparently, they sometimes get jammed inside, and unbolting them from the engine block and tapping them lightly (too hard will damage them) and re-installing them will sort them out (or they may be knackered).
It's worth trying, as it's free to do.

Posted: Thu Jul 22, 2010 7:05 pm

Cheers Type17 I'll give that a try in the morning. By the way, you have a 16v right? Do you have the ability to read codes from the engine? If so can you tell me what you use? Mines a '93, I've seen your pic of the fuses, is this inside the car,or in the engine bay, just in front of the steering wheel as it were. Basically, anything you can tell me about getting codes out of the 2ltr 16v (ACE) engine will be a great help Very Happy

I've seen you can build your own, plus looking online there's a few cheap readers, £25ish on amazon...

http://www.amazon.co.uk/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=vagcom&x=0&y=0&ih=6_0_0_0_0_0_0_0_0_1.96_2543&fsc=-1

Thanks again

Rog

Posted: Thu Jul 22, 2010 7:27 pm

The fuse picture is of the stuff under the bonnet in front of the steering wheel.

I can read my ACE with a VAG.COM cable and software, which I actually bought for my wife's 2004 Mk5 Golf.
The Audi only has two controllers (ECU and ABS), whereas the Golf has over 30, including one for each door(!). However, the VAG.COM stuff is over $200, and isn't worth it for an Audi 80, as the info provided is very sparse.
I've found that many garages' reader systems are unable to read the ACE ECU, as it is very primitive, but you may be lucky if the guy has a good system and/or knows what he's doing.
I've also found that the fault readers for the 8v ECU do NOT work with the ACE setup - the Draper one I bought got fried when I plugged it in - the wiring in the diagnostic ports is different.

By the way, even with the VAG.COM reader to hand, I've never found any useful codes from my Audi - even when the lambda was knackered, the code was (all ok, no faults found) - I tend to ignore the fact that the car has any OBD capabilities at all, and concentrate on troubleshooting the 'old fashioned' way, such as testing components with a multimeter, visual examination, swapping with known good versions, etc.

Posted: Thu Jul 22, 2010 7:35 pm

Cheers Type17 - Sounds like I'll be saving myself some money then.

Going back to my pinking, and the cam chain stuff, I'm tempted to have a go myself at both the cam belt and cam chain, as I think I've mentioned, or at least implied, I'm no mechanic, I just read the stuff you guys post and go and give it a go Smile

Anyway, I've done a cam belt on an old 8v Mk1 GTI, wasn't difficult, probably an impossible question to answer, but do you think the cam belt/chain on my new 2ltr 16v could be a bridge too far for a beginner? Either way, how long are we looking at roughly? I've got time on my side, but it would be nice if I could get it done by Monday, otherwise I'll dust off the push bike!

Thanks again

Rog

Posted: Thu Jul 22, 2010 8:02 pm

If you were happy doing the Mk1 GTI (my old car, hence my username!), then the belt on the ACE is actually easier in some regards - the intermediate shaft on 16v engines isn't timed, as it only drives the oil pump (it also drives the distributor on 8v engines). On the downside, the radiator and fans make space very tight, so you'll need to at least remove the fans from the rad, if not the rad itself (there is a plug to unplug the fans, but it is really well-hidden, under the chassis leg).
Here's some info on doing the belt: http://www.audifans.net/ftopict-19745-belt.html
...and you've referenced above the info I wrote up on doing the chain - read all that, and consider each step, given what you know about your engine - if each step makes sense, then you should be fine.

The trickiest bit is opening/closing the bearing caps on the cams - if you open nuts too far, compared to their partners, the caps jam on the studs, and you have to tighten the loosest one a little to free things up again, but it just takes patience.

No special tools are required, other than a torque wrench fo rthe cam bearing caps, a good socket set, and good Allen key set-up (slim, correct extensions, etc) that will allow you to access all of the inlet manifold bolts (confirm you can open all of them before doing anything else)

Posted: Thu Jul 22, 2010 8:13 pm

Final tip: Don't try to start it when finished - turn the engine over with a spanner on the crank pulley (never the cam pulley, you'll damage the belt) to see if you got it right(!) - if the engine won't turn over twice (twice at the crank, to get the cam turned over once), then you haven't done it right. Also, do this test before you put the cam-cover back on, so you can see if the circles on the cam-cogs line up.

Posted: Thu Jul 22, 2010 8:41 pm

So you're not telling me to avoid the job like the plague then! Very Happy

When I did my GTI cam belt, again based on forum guides, I turned the engine over several times by hand, but being a non-interference engine I couldn't go too far wrong.

I now need to find a comprehensive guide for the cam belt change, which I imagine will be on here, but wasn't in the FAQ section as I'd hoped, I want to know what do I need to take out/remove to get to the belt, pulleys, etc to start with. Looks like the radiator fans being removed will help, don't really want to pull the radiator unless its necessary or really helpful, other than that I'm in the dark...

Thanks again

Rog

Posted: Thu Jul 22, 2010 8:46 pm

If you've done the Mk1 GTI 8v belt, then it's virtually the same - the crank timing mark is the same, and the cam one is even easier to read than the 8v one (big arrow cast into the cam-cover).

Posted: Thu Jul 22, 2010 9:04 pm

Will I need to remove the radiator fans and/or radiator? When I was looking in there earlier in the week when I was going to replace the alternator and hydraulic pump belts, I thought it all looked a bit of a tight squeeze :/

Thanks again

Rog

Posted: Thu Jul 22, 2010 9:14 pm

Yes, remove the fans at least - the hassle of trying to work with them in place would outweigh the trouble of removing them at the beginning and replacing them at the end.

I went the whole way and drained the coolant and removed the rad, but I'd say that you'd get by with just the fans out.

Posted: Thu Jul 22, 2010 9:50 pm

Just realised I'd missed one of your earlier posts where you've linked to a previous post you've detailed the cam belt change, so thanks for that. The bit about the wiring to the radiator fans sounds a little odd, I get the impression I can't just disconnect the wiring for some reason, but as you say it can just be carefully placed up on the wing out of the way seems good enough for me.

I have to say the whole timing bit bothers me, even though I know I'll be able to turn the engine over by hand several times to ensure I've not cocked anything up, it still bothers me, but I love trying to do this stuff myself, I enjoy the learning and saving the cash! All the business of lining the various timing marks up, you say these are obvious, so do I just turn the engine over by hand at the start to get them lined up at the top as it were, then begin taking everything apart? I assume my engine is pretty much timed correctly otherwise it wouldn't run, so as I say, turning it over by hand, keeping an eye on a particular timing mark until it points to the relevant place (to the top?) everything should be lined up as necessary? There must be some pictures floating about with the various marks I'm looking for and with everything in the right position as it were. Pop off the other belts and pulleys where necessary, take off the cam belt cover, remove the cam belt tensioner, then I should be able to take off the cam belt and put on the new belt and tensioner? Then I can follow your guide for the cam chain. I'm just making most of this up as I go along, in case you hadn't realised Smile

I did the belt on the GTI 4 years ago when I got the car, only because I didn't like the Tappets ticking and found a guide to cleaning up your Tappets, the same one this forum uses I believe, anyway in my haste I took all the belts and bits off without marking anything up, and only when I came to putting the bits back together was it pointed out to me that using the markings, the ones I hadn't made, would allow me to easily get everything back in and correctly timed, doh! Anyway I found another guide on how to get your car set back up when there are no markings, but I still took it to my mechanic friend after I'd put it back together to get him to adjust the timing as it was out by a bit.

Thanks again Type17 for all your help on this, and sorry for all my waffle :/

Rog

Posted: Thu Jul 22, 2010 10:46 pm

When I wrote that in '07, I couldn't find the plug for disconnecting the rad fans, despite extensive searching - it's so hard to see, that I only realised that there was one when I got to examine the engine bay of a scrap 80, which had had the engine removed!

Posted: Thu Jul 22, 2010 11:05 pm

Thanks for the picture in the other link, its all helping, I'm starting to get excited, or is that anxious? Anyway, I'm picking up a new chain, dizzy cap and rotor arm in the morning, so then I can take a look and see if I'm feeling brave enough to have a go.

In the mean time, seeing as you don't seem to be in a rush to go to bed...

In your post with the picture, the guy mentions something about struggling to remove the pulley, and used some bolts to remove it, do you have a better explanation, I vaguely remember having trouble getting a pulley off when doing my GTI, I think I did something odd like get a large socket wrench and jam it on the pulley and the wrench handle reached the ground so as to stop the pulley turning, its late and I'm probably talking crap, but it does ring bells...

One last thing, in another post some has told me that when I come to replace the rotor arm the old one will be glued on and will need breaking off with pliers, yet the new one will just push on, you being the 16v guru, does this sound normal to you?

Thanks again and now its time for me to go to bed =)

Rog

Posted: Thu Jul 22, 2010 11:08 pm

One last thing before bed, is this about right? Its for the 20v, but its very detailed, not sure if it will help me or confuse me, if the steps are the same then great, otherwise I'll ignore it for fear of getting muddled Smile

http://www.20v.org/belts.htm

Thanks again

Rog

Posted: Thu Jul 22, 2010 11:16 pm

You only need to open the four 6mm allen bolts see pic in other thread - you do need to stop the pulley rotating to do that - I use a scrap v-belt clamped in a vice-grips to hold it (get a friend to hold it while you tackle the bolts (top tip: clean out the allen hex-holes and be sure that your allen key is fully in, then hit the wrench with a hammer to crack them open - pulling long and hard with a long lever will round out the hex in the bolt-head, but a sharp whack won't)

Posted: Thu Jul 22, 2010 11:19 pm

There are enough differences with 5-cyl engines (parts that don't exist in ACE engine, different bolt arrangements, torque settings, etc) that you probably should ignore that page, really.

Posted: Fri Jul 23, 2010 7:18 am

Thanks again Type17(Steve?), I'm off to pick up the parts in a bit so will be running through it all in my head, just watch how I have a go a bit later and come back on here asking how the hell the radiator comes out, that's my normal luck, I tend to get tripped up before I start!

Thanks again

Rog

Posted: Fri Jul 23, 2010 6:29 pm

Well some progress, but by no means finished.

All inlet manifold bolts undid without rounding.

I've only removed the rad fans, see what you mean about the wiring, bit of a git to get to, but got them out in the end.

The long hex bolt holding the top cam belt cover on was a bit rounded, and I ended up having to use my Irwin bolt grippers to remove it, so new bolt will be needed on refitting.

Next I'm going to remove both alternator belt and PAS belt, there's a star bolt adjuster on the PAS belt same as the alternator, which is all I need to undo to get the two belts off, is this correct?

After that I can remove the spark plugs and turn the engine over by hand, using a spanner on the crank pulley?

I'm turning the crank pulley, until the 'V' mark on the top of the rocker cover, is in line with the blue timing indentation mark on the cam pulley are in line, depending on the 'cycle' of the engine this might take up to two turns of the crank.

Now I need to remove the crank pulley, 4 6mm allen bolts, this is where you suggest I use an old V-belt (one I just removed?) to trap the crank pulley, I'm still unclear on this bit. I've read that if the car is on the ground (all 4 wheels) and the hand brake on and in gear it will help give me some resistance when removing the crank pulley? That was on the 20v thread up above, is this only 20v applicable, or will it work on my 16v?

If in removing the crank pulley you end up cranking the engine out of sync (TDC) would you need to attach the pulley and start again, or is it still possible to crank it without the pulley?

After that remove the lower cam belt cover.

I've also read on the above 20v thread it will help to mark the old cam belt in several places whilst its still attached, count the number of teeth between the marks, then make similar marks on the new belt, as this will help ensure the new belt goes on as it should.

Am I right in thinking once I remove the old cam belt, I should do the cam chain bit now, as I'll need to take out both cams to remove the old chain, and fit the new chain? In removing the cam which I assume has got the cam pulley attached, so as long as the cam pulley is at TDC, I can lift it out and the other cam, do the chain as per your other guide, put them both back in only worrying that the cam with the pulley and timing mark are put back in the TDC position?

Sorry for all the questions again Steve, but I'm just hoping I've got it right, or you can correct me where necessary.

Thanks again

Rog

Posted: Fri Jul 23, 2010 7:21 pm

Looking good, you have it well sussed. I've made a few comments below IN CAPS, FOR CLARITY.

All inlet manifold bolts undid without rounding.

I've only removed the rad fans, see what you mean about the wiring, bit of a git to get to, but got them out in the end.

The long hex bolt holding the top cam belt cover on was a bit rounded, and I ended up having to use my Irwin bolt grippers to remove it, so new bolt will be needed on refitting.

Next I'm going to remove both alternator belt and PAS belt, there's a star bolt adjuster on the PAS belt same as the alternator, which is all I need to undo to get the two belts off, is this correct?
YES, LOOSEN ALL THE OTHER BOLTS A FEW TURNS, SO THAT THE PUMP/ALTERNATOR BODIES CAN MOVE TO SLACKEN THE BELTS

After that I can remove the spark plugs and turn the engine over by hand, using a spanner on the crank pulley?
YES.

I'm turning the crank pulley, until the 'V' mark on the top of the rocker cover, is in line with the blue timing indentation mark on the cam pulley are in line, depending on the 'cycle' of the engine this might take up to two turns of the crank.
CORRECT.

Now I need to remove the crank pulley, 4 6mm allen bolts, this is where you suggest I use an old V-belt (one I just removed?) to trap the crank pulley, I'm still unclear on this bit. I've read that if the car is on the ground (all 4 wheels) and the hand brake on and in gear it will help give me some resistance when removing the crank pulley? That was on the 20v thread up above, is this only 20v applicable, or will it work on my 16v?
THAT'LL WORK FINE, I USED AN OLD BELT BECAUSE THE ENGINE WAS OUT OF THE CAR, BUT YOU CAN JUST PUT THE CAR IN 5TH AND USE THE HANDBRAKE TO BE SURE IT WON'T MOVE, AND THEN (TOP TIP) 'JERK' THE BOLTS OPEN RATHER THAN JUST PULLING HARD.

If in removing the crank pulley you end up cranking the engine out of sync (TDC) would you need to attach the pulley and start again, or is it still possible to crank it without the pulley?
YOU CAN STILL MOVE IT BACK AND FORTH, AS THE PART YOU ARE REMOVING ONLY CARRIES THE V-BELTS, AND ULESS YOU MOVED IT A MILE, YOU CAN USE THE CAM-PULLEY MARKS TO GET BACK TO TDC (IF THE BELT IS STILL ON. IF IT'S OFF, YOU MAY HAVE TO LOOSELY RE-FIT THE LOWER CAMBELT COVER AND V-BELT PULLEY FOR A SEC, TO GET BACK TO TDC). PS: NOTE THAT ONE OF THE V-BELT PULLEY'S FOUR BOLT-HOLES IS ALIGNED 'OUT-OF-SYNC' SO THAT YOU CAN ONLY PUT IT BACK IN THE RIGHT ORIENTATION.

After that remove the lower cam belt cover.
YES

I've also read on the above 20v thread it will help to mark the old cam belt in several places whilst its still attached, count the number of teeth between the marks, then make similar marks on the new belt, as this will help ensure the new belt goes on as it should.
I'VE NEVER DONE THAT BUT IT WOULD WORK FINE, SO GO AHEAD

Am I right in thinking once I remove the old cam belt, I should do the cam chain bit now, as I'll need to take out both cams to remove the old chain, and fit the new chain?
YES.

In removing the cam which I assume has got the cam pulley attached, so as long as the cam pulley is at TDC, I can lift it out and the other cam, do the chain as per your other guide, put them both back in only worrying that the cam with the pulley and timing mark are put back in the TDC position?
WHEN DOING THE CHAIN, IGNORE THE PULLEY AND BELT TIMING MARKS FOR A WHILE, AND CONCENTRATE ON THE CIRCLES STAMPED IN THE CHAIN PULLEYS (SEE OTHER GUIDE) - WHEN YOU GET THOSE ONES RIGHT, THE MARKS FOR THE CAM BELT-PULLEY WILL ALSO BE RIGHT, READY FOR THE REFITTING OF THE BELT.