Hi guys. :hi:
I hope you are all well and staying safe during this crisis.
Sorry for the more or less long read, it's a pretty weird issue, a lot of odd symptoms, and I just haven't been successful at finding the solution yet.
If you take the time to read this, just know that I very appreciative. I've read every article on idling issues, checked videos, thought outside the box, but can't figure it out. Or maybe I did?
I have an idling issue, which seems to translate to the clutch/transmission I've done almost everything to fix it, but nothing has worked so far. I am starting to think it may be bad catalytics/exhaust manifolds but I am hoping that someone who's experienced this problem or knows about it could help me out shed some light on the problem.
NOTE: The car does not throw any codes or check engine light, so that doesn't help.
The car has some idling and driveability issues mostly when it reaches normal operating temperatures. Once the car is warm, it will idle a little rough, below the ideal rpm. The longer I'm in traffic, the little worse it gets. I may be at times idling at a red light in neutral, when the rpm would suddenly drop furthermore, causing a little rumble of the engine. It never stalls but sometimes it feels like it could. In the worst case, it will drop low enough to cause the red check engine light to very briefly light up, and then it will rev back up a little to adjust itself. I would say it otherwise drives pretty well at normal speeds, in the higher rpm range, or on the highway.
However, the idling issue alone is not the worst part. When the problem occurs, clutching starts feeling very odd and annoying in low gears/low rpm. When I release the clutch pedal, the engine would not always smoothly engage, it will have trouble to synchronize with the transmission making it a little shaky before it smooths out a little again. On idle, the engine may also sometimes start to tick, like it's misfiring or something, but the tick sometimes goes away, and almost never does it on cold starts. This problem has made clutching in 1st or reverse while trying to control the revs very difficult, and manoeuvring the car at low speeds in general became very frustrating. The clutch also, for the 2nd time around, developed a major squeak when depressing and releasing the pedal. This may or may not be related to the rest of the issue, but I'll tell you in a moment why I suspect it to be part of it, and it's also worse when the car is warm.
Car has (150 000km) 93 000 original miles
So far I've:
- Changed all vacuum hoses, lines and plugs
- Checked for vacuum leaks (built a smoke machine)
- Changed the CCV
- Changed all ignition coils
- Changed spark plugs (Bosch)
- Rebuilt the DISA valve (new aluminum flap)
- Rebuilt the VANOS (was unnecessary)
- Changed to a new heavy duty battery like 2 years ago (not a cheap one)
- Changed all 4 oxygen sensors (Bosch)
- I also got a brand new DME singlemass clutch kit (flywheel/disc/pressure plate/throw-out bearing & pilot bearing and even got a brass clutch fork pivot ball and changed both the master and slave cylinders).
I didn't change any of the original fuel injectors, but from reading about them and the symptoms of fuel related idling problems, I don't think they are the problem. I did however recently change the fuel pump and fuel filter as well.
So after some research, I started thinking it's the catalytics, here's why. First a little throwback to summer 2019, I removed the engine due to a broken tranny bell housing bolt, and a set of disgusting aftermarket catless headers that were installed incorrectly by the previous owner. They were leaking between the exhaust valves and exhaust manifold flange, I thought some studs were broken into the block and that I'd have to drill them out, so in rage and excitement I went ahead and removed the engine from the car to fix all of that :loco:. That's when I replaced the whole clutch system, removed the ugly headers, and put back on the OEM used catalytic converters that the previous owner had sold me with the car. They weren't supposed to have a lot of mileage on them since he had used aftermarket headers early in the car's existence, and they indeed looked nice and clean. I did a few other preventive fixes such as replacing the oil pan, oil housing, and valve cover gaskets, pulleys and stuff like that while it was easier with the engine out, but nothing I can think of that would cause this problem. * I did not open the engine itself any more at all *
So anyway, when I fired the car back up again after the huge job that took all my weekends for 3 months, the issue started to occur. At first the idling issue was major, I didn't have any check engine light on per say, but I will admit the reader was in fact throwing codes at first. It seems like it was all vacuum related, so I went through all the hoses, caps, lines, and boots, tightened everything, and no more codes, and the engine started running much better again, but not perfect since I'm still stuck with the current problem.
Considering everything I've done, and thoroughly checked for vacuum leaks, this couldn't be one. So I started suspecting the cats when a faint smell of rotten eggs started to appear. It rarely happens but it does occur at times, and comes right into the cabin when I'm driving, and no I didn't fart. I read that only cats can smell like that, and oddly enough it started occurring only after I had installed the old OEM cats.
So after noticing the smell, I plugged an OBD tool, checked the live feed of the PRE and POST cats sensors with the engine warm and the PRE cats readings show a normal up and down oscillation in voltage, but the POST cats sensors do not keep a more or less steady line (voltage), as they are apparently supposed to if your cats are working well. Sometimes the POST cats readings will show a drastic drop here and there as I'm driving and revving the car.
So about that clutch squeak... After I had changed the clutch system to a new beefier one, the pedal was at first smooth, no squeak, easier to clutch although the idling/clutching problem was present since the very beginning of throwing the engine back in the car (only when warm), the smooth clutch still made it ok to drive at first though. A month or so in however, the clutch developed a major squeak like I said, it happens when I depress the clutch pedal, it's worse when the car warms up, and towards the end of pressing the pedal in, it becomes harder and it feels like there's more friction at the throw-out bearing. Now I know dirty/clogged cats can heat up more than usual, and I started thinking what if the hot cats are heating up the transmission to higher than normal temperatures, compromising the lubricant used on the throw-out bearing? After all it sit right next to the cats right?, So I once jacked up the car after a drive, touched the bell housing, and not sure how hot or not it is supposed to be, but they felt somewhat hot to me.
But then I said no, I probably just screwed up used the wrong lube, after all I am no master mechanic, this is all new to me, and this project now has just become a nightmarish hobby. So before I went on further investigating the idling problem, I had made a much bigger booboo trying to fix that new agony inducing squeak, which was more annoying than the original idling issue itself at that point, because the more it's warm and squeaks, the more you feel that grind/harder pressure in the clutch pedal . So I did some research and found out that the wrong lube could indeed cause the squeak, because over time it will attract dirt/metal particles from normal clutch operation. It made total sense to me, so I tried to spray dry lubricant onto the throw-out bearing and the shaft it slides on, through the only place possible without removing the tranny; the slave cylinder opening. When I put the slave cylinder back on, I misaligned it, and when I pressed the clutch in...BOOM, my new slave cylinder exploded into the bell housing, brake fluid started to leak all over the place :facepalm:. I wanted to literally cry, and so I said F*** IT! :ben: Went to a popular shop who deals with only German cars, and had them pull the tranny, remove the broken parts, clean the bell housing, re-torque, re-lube, and re-install everything. I also had told them about my idling issue and the suspicious cats, which would be easier to change without the tranny in the way, and had asked them to changed them also for the sake of it. After they closely inspected them though, they said they looked clean and that I shouldn't change them just now, but to change the CCV instead, which was still the original one, and according to them could be the actual cause of my driveability and idling issues. They had scanned the car for other issues and codes but couldn't find anything.
So they changed the CCV, left the OEM catalytics on. When I drove out of the shop, the clutch felt super smooth again. They had also suggested I might've used the wrong lube on the throw-out bearing and that it was causing the squeak and that it should be fine from now on. So I was once again a little happier, the clutch was easy to operate and wasn't squeaking at all. However, the idling issue was still present. It felt maybe just a tad better with the clutch being smooth again, and the new CCV, but the problem is still persisting. I thought I could live with it for now as long as the clutch operates smoothly, but GUESS WHAT!? A month in again, the clutch developed the same nasty squeak, and this time around it was fixed by professionals, with proper lubing supposedly. So could my theory on the bad/hotter than normal cats compromising clutch operation be a real thing? Because slightly blocked cats could also create back pressure, making it harder for the engine to run smooth and thus causing idling and driveability issues no? Or maybe the clutch and idling issues are unrelated? Either way I need feedback.
So to sum it all up; occasional rotten eggs smell, idling and clutching issue mostly when the car is warm, clutch developing a squeak over time that is worse when warm, engine ticking at odd times. Could it really really really be the catalytics causing all of that?
I'm obsessed with this now. I need to get to the bottom of this and find out what's causing all my issues . To be honest, I plan to get the catalytics changed no matter what this summer, but has anyone ever had a similar issue? Am I going insane (definitely). I just want to understand!
When you work so hard on something, it's just got to work. Are the clutching and idling problems even related? It sure feels like it.
Any comments or advice again is greatly appreciated, thanks so much for reading. You all stay safe!
I hope you are all well and staying safe during this crisis.
Sorry for the more or less long read, it's a pretty weird issue, a lot of odd symptoms, and I just haven't been successful at finding the solution yet.
If you take the time to read this, just know that I very appreciative. I've read every article on idling issues, checked videos, thought outside the box, but can't figure it out. Or maybe I did?
I have an idling issue, which seems to translate to the clutch/transmission I've done almost everything to fix it, but nothing has worked so far. I am starting to think it may be bad catalytics/exhaust manifolds but I am hoping that someone who's experienced this problem or knows about it could help me out shed some light on the problem.
NOTE: The car does not throw any codes or check engine light, so that doesn't help.
The car has some idling and driveability issues mostly when it reaches normal operating temperatures. Once the car is warm, it will idle a little rough, below the ideal rpm. The longer I'm in traffic, the little worse it gets. I may be at times idling at a red light in neutral, when the rpm would suddenly drop furthermore, causing a little rumble of the engine. It never stalls but sometimes it feels like it could. In the worst case, it will drop low enough to cause the red check engine light to very briefly light up, and then it will rev back up a little to adjust itself. I would say it otherwise drives pretty well at normal speeds, in the higher rpm range, or on the highway.
However, the idling issue alone is not the worst part. When the problem occurs, clutching starts feeling very odd and annoying in low gears/low rpm. When I release the clutch pedal, the engine would not always smoothly engage, it will have trouble to synchronize with the transmission making it a little shaky before it smooths out a little again. On idle, the engine may also sometimes start to tick, like it's misfiring or something, but the tick sometimes goes away, and almost never does it on cold starts. This problem has made clutching in 1st or reverse while trying to control the revs very difficult, and manoeuvring the car at low speeds in general became very frustrating. The clutch also, for the 2nd time around, developed a major squeak when depressing and releasing the pedal. This may or may not be related to the rest of the issue, but I'll tell you in a moment why I suspect it to be part of it, and it's also worse when the car is warm.
Car has (150 000km) 93 000 original miles
So far I've:
- Changed all vacuum hoses, lines and plugs
- Checked for vacuum leaks (built a smoke machine)
- Changed the CCV
- Changed all ignition coils
- Changed spark plugs (Bosch)
- Rebuilt the DISA valve (new aluminum flap)
- Rebuilt the VANOS (was unnecessary)
- Changed to a new heavy duty battery like 2 years ago (not a cheap one)
- Changed all 4 oxygen sensors (Bosch)
- I also got a brand new DME singlemass clutch kit (flywheel/disc/pressure plate/throw-out bearing & pilot bearing and even got a brass clutch fork pivot ball and changed both the master and slave cylinders).
I didn't change any of the original fuel injectors, but from reading about them and the symptoms of fuel related idling problems, I don't think they are the problem. I did however recently change the fuel pump and fuel filter as well.
So after some research, I started thinking it's the catalytics, here's why. First a little throwback to summer 2019, I removed the engine due to a broken tranny bell housing bolt, and a set of disgusting aftermarket catless headers that were installed incorrectly by the previous owner. They were leaking between the exhaust valves and exhaust manifold flange, I thought some studs were broken into the block and that I'd have to drill them out, so in rage and excitement I went ahead and removed the engine from the car to fix all of that :loco:. That's when I replaced the whole clutch system, removed the ugly headers, and put back on the OEM used catalytic converters that the previous owner had sold me with the car. They weren't supposed to have a lot of mileage on them since he had used aftermarket headers early in the car's existence, and they indeed looked nice and clean. I did a few other preventive fixes such as replacing the oil pan, oil housing, and valve cover gaskets, pulleys and stuff like that while it was easier with the engine out, but nothing I can think of that would cause this problem. * I did not open the engine itself any more at all *
So anyway, when I fired the car back up again after the huge job that took all my weekends for 3 months, the issue started to occur. At first the idling issue was major, I didn't have any check engine light on per say, but I will admit the reader was in fact throwing codes at first. It seems like it was all vacuum related, so I went through all the hoses, caps, lines, and boots, tightened everything, and no more codes, and the engine started running much better again, but not perfect since I'm still stuck with the current problem.
Considering everything I've done, and thoroughly checked for vacuum leaks, this couldn't be one. So I started suspecting the cats when a faint smell of rotten eggs started to appear. It rarely happens but it does occur at times, and comes right into the cabin when I'm driving, and no I didn't fart. I read that only cats can smell like that, and oddly enough it started occurring only after I had installed the old OEM cats.
So after noticing the smell, I plugged an OBD tool, checked the live feed of the PRE and POST cats sensors with the engine warm and the PRE cats readings show a normal up and down oscillation in voltage, but the POST cats sensors do not keep a more or less steady line (voltage), as they are apparently supposed to if your cats are working well. Sometimes the POST cats readings will show a drastic drop here and there as I'm driving and revving the car.
So about that clutch squeak... After I had changed the clutch system to a new beefier one, the pedal was at first smooth, no squeak, easier to clutch although the idling/clutching problem was present since the very beginning of throwing the engine back in the car (only when warm), the smooth clutch still made it ok to drive at first though. A month or so in however, the clutch developed a major squeak like I said, it happens when I depress the clutch pedal, it's worse when the car warms up, and towards the end of pressing the pedal in, it becomes harder and it feels like there's more friction at the throw-out bearing. Now I know dirty/clogged cats can heat up more than usual, and I started thinking what if the hot cats are heating up the transmission to higher than normal temperatures, compromising the lubricant used on the throw-out bearing? After all it sit right next to the cats right?, So I once jacked up the car after a drive, touched the bell housing, and not sure how hot or not it is supposed to be, but they felt somewhat hot to me.
But then I said no, I probably just screwed up used the wrong lube, after all I am no master mechanic, this is all new to me, and this project now has just become a nightmarish hobby. So before I went on further investigating the idling problem, I had made a much bigger booboo trying to fix that new agony inducing squeak, which was more annoying than the original idling issue itself at that point, because the more it's warm and squeaks, the more you feel that grind/harder pressure in the clutch pedal . So I did some research and found out that the wrong lube could indeed cause the squeak, because over time it will attract dirt/metal particles from normal clutch operation. It made total sense to me, so I tried to spray dry lubricant onto the throw-out bearing and the shaft it slides on, through the only place possible without removing the tranny; the slave cylinder opening. When I put the slave cylinder back on, I misaligned it, and when I pressed the clutch in...BOOM, my new slave cylinder exploded into the bell housing, brake fluid started to leak all over the place :facepalm:. I wanted to literally cry, and so I said F*** IT! :ben: Went to a popular shop who deals with only German cars, and had them pull the tranny, remove the broken parts, clean the bell housing, re-torque, re-lube, and re-install everything. I also had told them about my idling issue and the suspicious cats, which would be easier to change without the tranny in the way, and had asked them to changed them also for the sake of it. After they closely inspected them though, they said they looked clean and that I shouldn't change them just now, but to change the CCV instead, which was still the original one, and according to them could be the actual cause of my driveability and idling issues. They had scanned the car for other issues and codes but couldn't find anything.
So they changed the CCV, left the OEM catalytics on. When I drove out of the shop, the clutch felt super smooth again. They had also suggested I might've used the wrong lube on the throw-out bearing and that it was causing the squeak and that it should be fine from now on. So I was once again a little happier, the clutch was easy to operate and wasn't squeaking at all. However, the idling issue was still present. It felt maybe just a tad better with the clutch being smooth again, and the new CCV, but the problem is still persisting. I thought I could live with it for now as long as the clutch operates smoothly, but GUESS WHAT!? A month in again, the clutch developed the same nasty squeak, and this time around it was fixed by professionals, with proper lubing supposedly. So could my theory on the bad/hotter than normal cats compromising clutch operation be a real thing? Because slightly blocked cats could also create back pressure, making it harder for the engine to run smooth and thus causing idling and driveability issues no? Or maybe the clutch and idling issues are unrelated? Either way I need feedback.
So to sum it all up; occasional rotten eggs smell, idling and clutching issue mostly when the car is warm, clutch developing a squeak over time that is worse when warm, engine ticking at odd times. Could it really really really be the catalytics causing all of that?
I'm obsessed with this now. I need to get to the bottom of this and find out what's causing all my issues . To be honest, I plan to get the catalytics changed no matter what this summer, but has anyone ever had a similar issue? Am I going insane (definitely). I just want to understand!
When you work so hard on something, it's just got to work. Are the clutching and idling problems even related? It sure feels like it.
Any comments or advice again is greatly appreciated, thanks so much for reading. You all stay safe!
