Engine "chatter" - What can be wrong?
08-26-2005, 06:14 AM
#16
Instructor
Yep that's the little fella Jason, as I mentioned, i had a hell of a time finding out what the problem was and my specialist (JZ Machtech) UK couldn't sort it. As soon as I made this little mod no more pinging!! hope it works for you
Ash
Ash
08-26-2005, 09:21 AM
#17
Race Car
Originally Posted by ASH.PALIN
Hi jason,
I had exactly the same problem, for me, what solved it was the adaption of a small y-cord splitter that lives on the left hand side of the varioram induction tucked back in there. This spiltter collapses with time and effects advance/retard, causing the pinging/knocking /rattling under load. You can effect a repair with a small piece of 8mm brass tubing, there is a thread on this very problem on the board somewhere, perhaps some clever johnny can direct you to it, it certainly solved this very annoying problem for me.
Ash
I had exactly the same problem, for me, what solved it was the adaption of a small y-cord splitter that lives on the left hand side of the varioram induction tucked back in there. This spiltter collapses with time and effects advance/retard, causing the pinging/knocking /rattling under load. You can effect a repair with a small piece of 8mm brass tubing, there is a thread on this very problem on the board somewhere, perhaps some clever johnny can direct you to it, it certainly solved this very annoying problem for me.
Ash
Has he got a heat shield that is coming loose and rattles, maybe behind the cats? Or how about an exhaust clamp? To me it sounds like a rattle. It doesn't follow the entire rpm range, doesn't do it under hard excel, he has no loss of power or feel anything funky in the drivetrain.......
just my .0002 cents
08-26-2005, 07:57 PM
#19
Racer
Thread Starter
Originally Posted by 993inNC
???? The description is of a noise at light to mild excel. That 'ram valve only comes in at WOT after 5K rpm. Also, I would think if it was a rubbing on metal problem, wouldn't it get much worse under hard excel?
Has he got a heat shield that is coming loose and rattles, maybe behind the cats? Or how about an exhaust clamp? To me it sounds like a rattle. It doesn't follow the entire rpm range, doesn't do it under hard excel, he has no loss of power or feel anything funky in the drivetrain.......
just my .0002 cents
Has he got a heat shield that is coming loose and rattles, maybe behind the cats? Or how about an exhaust clamp? To me it sounds like a rattle. It doesn't follow the entire rpm range, doesn't do it under hard excel, he has no loss of power or feel anything funky in the drivetrain.......
just my .0002 cents
Chris, I don't think it's some loose part making the noise in the engine as it happens only when the engine is hot. It makes the most "rattle" under very light throttle (just enough gas to maintain at a certain speed) between 2000 - 2500 rpm - correction from previous post. Any advice?
Originally Posted by kkim
...FWIW, pinging, to me, sounds like marbles being rattled around in a metal can that has been wrapped in a blanket. Is that similar to the sound you're hearing?
08-26-2005, 08:11 PM
#20
Addict
Rennlist Member
Rennlist Member
Jason,
From my experience, pinging usually happens under very heavy load with large throttle openings. With this happening to you at 2000rpm at light throttle, it doesn't add up to pinging, in my book.
Are there any more symptoms or conditions you could provide that could help w/ diagnosis? How many miles on your car and what kind of driver was the PO? Usage? Have you tried a different gas station or brand to see if that might make a diff?
When you checked the vacuum distributor, did you try to follow the lines to see if the other ends were plugged in?
From my experience, pinging usually happens under very heavy load with large throttle openings. With this happening to you at 2000rpm at light throttle, it doesn't add up to pinging, in my book.
Are there any more symptoms or conditions you could provide that could help w/ diagnosis? How many miles on your car and what kind of driver was the PO? Usage? Have you tried a different gas station or brand to see if that might make a diff?
When you checked the vacuum distributor, did you try to follow the lines to see if the other ends were plugged in?
08-26-2005, 08:20 PM
#21
Racer
Thread Starter
Originally Posted by kkim
Jason,
From my experience, pinging usually happens under very heavy load with large throttle openings. With this happening to you at 2000rpm at light throttle, it doesn't add up to pinging, in my book.
Are there any more symptoms or conditions you could provide that could help w/ diagnosis? How many miles on your car and what kind of driver was the PO? Usage? Have you tried a different gas station or brand to see if that might make a diff?
When you checked the vacuum distributor, did you try to follow the lines to see if the other ends were plugged in?
From my experience, pinging usually happens under very heavy load with large throttle openings. With this happening to you at 2000rpm at light throttle, it doesn't add up to pinging, in my book.
Are there any more symptoms or conditions you could provide that could help w/ diagnosis? How many miles on your car and what kind of driver was the PO? Usage? Have you tried a different gas station or brand to see if that might make a diff?
When you checked the vacuum distributor, did you try to follow the lines to see if the other ends were plugged in?
It has about 35k, no idea about the PO as it was purchased from a dealership, I've used Shell and 76 beside Chevron (preference) but still the same. I have not check to see if any of the vacuum lines were plugged...but I will. Are the vacuum lines have anything to do with the noise? - timing retard? I thought they were for the Varioram. Thanks.
08-26-2005, 08:40 PM
#22
Addict
Rennlist Member
Rennlist Member
Originally Posted by jkuniverse
Are the vacuum lines have anything to do with the noise? - timing retard?
Originally Posted by ASH.PALIN
This spiltter collapses with time and effects advance/retard, causing the pinging/knocking /rattling under load.
08-27-2005, 12:11 AM
#23
Instructor
Yeah sorry Jason, didn't read your post carefully enough, just came off a night shoot (for an american movie actually) and was a bit spaced, but sorting out that little splitter sorted my car out Pinging wise and made a difference to it's overall performance.
Apparently kelly one of the vacuum lines on that splitter does go to a sensor which chats to the cpu, or so my specialist s rather sheepishly admitted when i fixed the car myself (with rennlist help of course!)
It does sound like a pinging problem tho' jason, that rattle really can sound like a mechanical rattle, mine was incredibly irritating and happened right across the rev range..........especially when the engine was hot
hope you sort it out mate
Apparently kelly one of the vacuum lines on that splitter does go to a sensor which chats to the cpu, or so my specialist s rather sheepishly admitted when i fixed the car myself (with rennlist help of course!)
It does sound like a pinging problem tho' jason, that rattle really can sound like a mechanical rattle, mine was incredibly irritating and happened right across the rev range..........especially when the engine was hot
hope you sort it out mate
08-27-2005, 01:05 AM
#24
Race Car
Jason,
My Targa made the same noise. I think it is muffler related. Either sediment in the muffler or something wrong with the heat shield. When I switched to the RSRs, my problem went away. Since I let my mechanic install them, I don't know the condition of the the heat shields.
The original mufflers did have what sounded like sand in them. It was not sand, just the steel wool like sound deadners getting old and loose.
Just another reason to get RSRs.
My Targa made the same noise. I think it is muffler related. Either sediment in the muffler or something wrong with the heat shield. When I switched to the RSRs, my problem went away. Since I let my mechanic install them, I don't know the condition of the the heat shields.
The original mufflers did have what sounded like sand in them. It was not sand, just the steel wool like sound deadners getting old and loose.
Just another reason to get RSRs.
08-27-2005, 02:42 AM
#25
Racer
Thread Starter
Originally Posted by ASH.PALIN
... but sorting out that little splitter sorted my car out Pinging wise and made a difference to it's overall performance.
Apparently kelly one of the vacuum lines on that splitter does go to a sensor which chats to the cpu, or so my specialist s rather sheepishly admitted when i fixed the car myself (with rennlist help of course!)
It does sound like a pinging problem tho' jason, that rattle really can sound like a mechanical rattle, mine was incredibly irritating and happened right across the rev range..........especially when the engine was hot
hope you sort it out mate
Apparently kelly one of the vacuum lines on that splitter does go to a sensor which chats to the cpu, or so my specialist s rather sheepishly admitted when i fixed the car myself (with rennlist help of course!)
It does sound like a pinging problem tho' jason, that rattle really can sound like a mechanical rattle, mine was incredibly irritating and happened right across the rev range..........especially when the engine was hot
hope you sort it out mate
Originally Posted by pjconner
Jason,
My Targa made the same noise. I think it is muffler related. Either sediment in the muffler or something wrong with the heat shield. When I switched to the RSRs, my problem went away. Since I let my mechanic install them, I don't know the condition of the the heat shields.
The original mufflers did have what sounded like sand in them. It was not sand, just the steel wool like sound deadners getting old and loose.
Just another reason to get RSRs.
My Targa made the same noise. I think it is muffler related. Either sediment in the muffler or something wrong with the heat shield. When I switched to the RSRs, my problem went away. Since I let my mechanic install them, I don't know the condition of the the heat shields.
The original mufflers did have what sounded like sand in them. It was not sand, just the steel wool like sound deadners getting old and loose.
Just another reason to get RSRs.
08-27-2005, 03:09 AM
#26
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OK, I have a 95 cab with 80K miles and I think my engine makes the same sound. Does not do it when the engine is cold, but it is noticable when HOT. I live in the San Jose area and have also noticed some pinging when i accelerate hard on a hilly road (such as rt9). Since I have a 95 it's not a vario-cam issue. I am wondering if it is related to the pinging, maybe it is a vacum advance problem. Any suggestions regarding where to start looking?
Bob
Bob
08-27-2005, 08:40 AM
#27
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just wondering if the noise could be coming from the transmission- due to replacement of the double weight flywheel clutch to light one?? Listening carefully this is more of gear sounding noise- although at times it does sound like marbles in a can.
08-27-2005, 08:47 AM
#28
It might be a pinging sound, but it is not pinging (or detonation). Not unless for some reason you are running very lean at such a low and specific rpm range. The fact that it does not do it with the clutch in would suggest a tranny issue. IMHO.
08-27-2005, 11:11 AM
#29
Make sure Your distributor belt is not broken. Both rotors should point the same direction when the cap is removed. If not, do not drive it anymore and have the belt replaced right away. There is a guy on RL who does it very reasonably...
08-27-2005, 01:36 PM
#30
Racer
Thread Starter
Originally Posted by Christer
It might be a pinging sound, but it is not pinging (or detonation). Not unless for some reason you are running very lean at such a low and specific rpm range. The fact that it does not do it with the clutch in would suggest a tranny issue. IMHO.