11-10-2016, 10:14 AM (This post was last modified: 11-10-2016, 10:17 AM by t3tom.)
Hello,
My 91 Suzuki Swift with a G13B SOHC 16V 4 cylinder engine (JDM spec. with 35,000 original miles) ) has unusual noises ONLY after fully warming up. At warm idle, it makes a periodic wow-wow sound (approximately 5 cycles per second at 650rpm) followed by 2 seconds of silence, and then the noise repeats.
At first, I thought it sounded like a bad timing belt tensioner bearing.
I confirmed that the noise was still present after warm up, by removing all belts (A/C, PS, alternator and water pump) and then running the engine briefly.
After changing the belt and tensioner using the instructions on your website (and FSM) the engine runs smoothly, but still produces a cyclic noise, though at a higher pitch than before. (The crank gear bolt seemed tight, and there was no rubbing noted on the timing belt cover. I did not check the bolt torque of 94 Ft lbs however.)
As before, after extended idling, an intermittent high pitch squeal (that sounds like a teapot whistling) can be heard. This squeal will come and go (anything above 750 rpm will make it quiet again.)
I have attached 2 sound files, which are before and after the timing belt/tensioner change. Both recordings were with all accessory drive belts removed and with engine fully warmed up. The engine runs smoothly otherwise and no misfire or driveability issues are noted.
I would appreciate your thoughts on what might be the cause of this noise?
EDIT: I tried to attach some MP3 or WAV sound files, but the forum would not let me post it.
(11-10-2016, 10:32 AM)t3tom Wrote: Until I figure out where to post the sound recordings, attached is an audio wave form JPEG picture that visually depicts the noise.
wave files are huge, they ,not compressed
mp3 are.
but need to be short....
use drop box. or some place that has huge space, here is tiny. 20mb jpgs...?
(11-10-2016, 10:32 AM)t3tom Wrote: Until I figure out where to post the sound recordings, attached is an audio wave form JPEG picture that visually depicts the noise.
wave files are huge, they ,not compressed
mp3 are.
but need to be short....
use drop box. or some place that has huge space, here is tiny. 20mb jpgs...?
Good idea. Will look into Dropbox. The MP3 files I want to link are very small (less than 30 seconds) , only 100Kb and 280Kb.
11-10-2016, 03:10 PM (This post was last modified: 11-10-2016, 03:13 PM by t3tom.)
(11-10-2016, 12:02 PM)t3tom Wrote:
(11-10-2016, 11:55 AM)fixkick Wrote:
(11-10-2016, 10:32 AM)t3tom Wrote: Until I figure out where to post the sound recordings, attached is an audio wave form JPEG picture that visually depicts the noise.
wave files are huge, they ,not compressed
mp3 are.
but need to be short....
use drop box. or some place that has huge space, here is tiny. 20mb jpgs...?
Good idea. Will look into Dropbox. The MP3 files I want to link are very small (less than 30 seconds) , only 100Kb and 280Kb.
I just created an engine sounds web page (LINK below) with 3 separate MP3 files on it. Please have a listen and let me know what your trained ear says!
hello and greetings.
dropping belts was savvy !! way to go.
There are many sounds, possible. some are simple others not so.
It sounds like rod knock but i cant hear the double knock of it. a rod like to knock twice, as it changes direction bottom and top of cylinder.
mains like to know lugging and engine up hill.
it can be piston slap, that is not a big deal. (if not piston cracked cause)
use %5 stethoscope and listen all over engine. Everywhere, even engine mounts. take your time,... http://www.fixkick.com/NOISE.html
1: the exhaust header end loves to fail.. if the doughnut gasket there, is bad , it sounds just like rods or mains bad. scary.!
SO I took my cave man stick or board and jammed it at header, and frame and reefed it over and bam, dead silent. (the cold chills ended )
2: then on the 97 the thing made this same class noise. found the rear mount on the huge aluminum MAIN AIR pipe mount broken, huge sounds. there.
this pipe ends up at the MAF. the head has a mount to it, that can fail at head mount or like mine broke the aluminum pipe tab mount. off, and even sucked air there
a double trouble failure.
that is my best idles here.
lots of places Noises can source. in and engine. IN ENGINE or anything connected to it. this engine shake it has no Silent shaft, tech,. off crank.
cheers.
Quote:I just created an engine sounds web page (LINK below) with 3 separate MP3 files on it. Please have a listen and let me know what your trained ear says!
11-11-2016, 01:51 AM (This post was last modified: 11-11-2016, 01:52 AM by fixkick.)
code 12, means ECU is happy
the ECU can only discover, dead sensors (but can show code 51, weak EGR)
and not weak sensors.
its very crude here. unlike say a 96+
it also remembers, if you unplug a sensor key on,
to erase DTC errors pull the DOME fuse,
but ive no idea where you harness maker wired, the ECU memory wire (dome)
here is my cheat sheet, drawing on your ECU, it tells you what ever pin does. http://www.fixkick.com/ECU/92-95MPI-eng-...e-huge.png
see pin A1, this was DOME, fuse, in the donor car. white wire, is DOME fuse. so we pulled the fuse to erase all DTC memory stored errors.
A1 must be tired to battery , not ignition power,
that is so it can't forget, it's a feature, you drive, you see CEL glow, you come home , set the diag jumper and it pulse out the error codes, you stored driving, even key on not running.
see my DLC2 pins, I added all pins, numbers and colors and the words.
it shows which pins are input and which are output
and I corrected the silly wiring error they had in the TPS idle circuit.
11-11-2016, 07:02 AM (This post was last modified: 11-11-2016, 07:10 AM by t3tom.)
(11-11-2016, 12:53 AM)fixkick Wrote: hello and greetings.
dropping belts was savvy !! way to go.
There are many sounds, possible. some are simple others not so.
It sounds like rod knock but i cant hear the double knock of it. a rod like to knock twice, as it changes direction bottom and top of cylinder.
mains like to know lugging and engine up hill.
it can be piston slap, that is not a big deal. (if not piston cracked cause)
use %5 stethoscope and listen all over engine. Everywhere, even engine mounts. take your time,... http://www.fixkick.com/NOISE.html
1: the exhaust header end loves to fail.. if the doughnut gasket there, is bad , it sounds just like rods or mains bad. scary.!
SO I took my cave man stick or board and jammed it at header, and frame and reefed it over and bam, dead silent. (the cold chills ended )
2: then on the 97 the thing made this same class noise. found the rear mount on the huge aluminum MAIN AIR pipe mount broken, huge sounds. there.
this pipe ends up at the MAF. the head has a mount to it, that can fail at head mount or like mine broke the aluminum pipe tab mount. off, and even sucked air there
a double trouble failure.
that is my best idles here.
lots of places Noises can source. in and engine. IN ENGINE or anything connected to it. this engine shake it has no Silent shaft, tech,. off crank.
cheers.
Quote:I just created an engine sounds web page (LINK below) with 3 separate MP3 files on it. Please have a listen and let me know what your trained ear says!
Thanks for these reference links and suggestions. I did not really notice any regular knocking sounds, especially if you listen to the last sound clip: [the 14 second long post timing belt change] sound clip I posted. http://g13sohctom.wixsite.com/suzuki/sounds
[edit] I have a feeling the timing belt tensioner was responsible for a small contribution to noise, as the old bearing was a bit rough when I replaced it with a new one.
The currently most noticeable noise is a regular, deep wow-wow sound that seems to be at half crankshaft speed, as the noise seems to sync with ignition firing pulses. (I will try to observe a timing light pulse while listening to the sounds to confirm this).
If the engine is allowed to fully warm up to stable operating temperature, there is an occasional [teapot whistle] type sound (like a metal on metal high pitched squealing sound) that comes and goes. I did not run the engine very long with the water pump belt disconnected, but was able to confirm that the squealing sound happens without the water pump belt. This car (a JDM Swift) has a check engine light (CEL) but it is not currently illuminated.
My Plans:
(1) Buy a stethoscope today and try to listen all over to isolate the location of the noise.
(2) Should also perform a spark plug short test to try to isolate whether a specific cylinder is producing the noise.
(3) Drain and inspect the Mobil 1 oil that is currently in the car for any material. (as well as change the oil filter). This oil is the same oil in the car as when the noise was first noticed.
(4) This weekend I will try to take it for a short drive (with water pump belt reconnected of course) to see if the noise is present under load (lugging). I have never noticed it in the past, and I have pretty sensitive ears.
(5) I'll post a few engine bay pictures so that you can see whether you think I should check some other components.
hi
may be vacuum leaks , they can whistle.
egr main diaphragm , crack can whistle. (behind #4 intake man tube)
ah forgot to say the rubber hose trick to one ear
move hose about find sounds, or sucking sounds, etc?
good luck, you seem on track.
cheers.
(11-11-2016, 07:02 AM)t3tom Wrote:
(11-11-2016, 12:53 AM)fixkick Wrote: hello and greetings.
dropping belts was savvy !! way to go.
There are many sounds, possible. some are simple others not so.
It sounds like rod knock but i cant hear the double knock of it. a rod like to knock twice, as it changes direction bottom and top of cylinder.
mains like to know lugging and engine up hill.
it can be piston slap, that is not a big deal. (if not piston cracked cause)
use %5 stethoscope and listen all over engine. Everywhere, even engine mounts. take your time,... http://www.fixkick.com/NOISE.html
1: the exhaust header end loves to fail.. if the doughnut gasket there, is bad , it sounds just like rods or mains bad. scary.!
SO I took my cave man stick or board and jammed it at header, and frame and reefed it over and bam, dead silent. (the cold chills ended )
2: then on the 97 the thing made this same class noise. found the rear mount on the huge aluminum MAIN AIR pipe mount broken, huge sounds. there.
this pipe ends up at the MAF. the head has a mount to it, that can fail at head mount or like mine broke the aluminum pipe tab mount. off, and even sucked air there
a double trouble failure.
that is my best idles here.
lots of places Noises can source. in and engine. IN ENGINE or anything connected to it. this engine shake it has no Silent shaft, tech,. off crank.
cheers.
Quote:I just created an engine sounds web page (LINK below) with 3 separate MP3 files on it. Please have a listen and let me know what your trained ear says!
Thanks for these reference links and suggestions. I did not really notice any regular knocking sounds, especially if you listen to the last sound clip: [the 14 second long post timing belt change] sound clip I posted. http://g13sohctom.wixsite.com/suzuki/sounds
[edit] I have a feeling the timing belt tensioner was responsible for a small contribution to noise, as the old bearing was a bit rough when I replaced it with a new one.
The currently most noticeable noise is a regular, deep wow-wow sound that seems to be at half crankshaft speed, as the noise seems to sync with ignition firing pulses. (I will try to observe a timing light pulse while listening to the sounds to confirm this).
If the engine is allowed to fully warm up to stable operating temperature, there is an occasional [teapot whistle] type sound (like a metal on metal high pitched squealing sound) that comes and goes. I did not run the engine very long with the water pump belt disconnected, but was able to confirm that the squealing sound happens without the water pump belt. This car (a JDM Swift) has a check engine light (CEL) but it is not currently illuminated.
My Plans:
(1) Buy a stethoscope today and try to listen all over to isolate the location of the noise.
(2) Should also perform a spark plug short test to try to isolate whether a specific cylinder is producing the noise.
(3) Drain and inspect the Mobil 1 oil that is currently in the car for any material. (as well as change the oil filter). This oil is the same oil in the car as when the noise was first noticed.
(4) This weekend I will try to take it for a short drive (with water pump belt reconnected of course) to see if the noise is present under load (lugging). I have never noticed it in the past, and I have pretty sensitive ears.
(5) I'll post a few engine bay pictures so that you can see whether you think I should check some other components.
Sorry for the long delay in reply. It actually had been raining or snowing for months it seems. I got distracted and only got back to it recently.
(1) Buy a stethoscope today and try to listen all over to isolate the location of the noise.
The stethoscope revealed no noises anywhere except when the probe was placed on the surfaces of the water pump housing, and on the timing belt tensioner stud bolt. The water pump provided a gravelly growling noise, and the timing belt tensioner stud produced a higher pitched rough squeak.
(2) Should also perform a spark plug short test to try to isolate whether a specific cylinder is producing the noise.
Shorting each cylinder produced no reduction in sound, only a decrease in idle speed.
(3) Drain and inspect the Mobil 1 oil that is currently in the car for any material. (as well as change the oil filter). This oil is the same oil in the car as when the noise was first noticed.
The oil in the oil filter and oil drain pan was clean and free of metallic particles or grit. I attached a mechanical oil pressure gauge to a port on an oil filter sandwich adapter plate (made by GlowShift) added between the oil filter and engine. I installed an OTC mechanical oil pressure test gauge and Autometer electric oil pressure gauge to the sandwich plate ports. Measured oil pressure at cold start and after warm up (when engine cooling fan kicked in) were 75 psi, and 25 psi respectively. The oil pressure between 3000 - 4000 RPM hot was also measured at between 65-75 psi, which are within the factory specification for this engine.
(4) This weekend I will try to take it for a short drive (with water pump belt reconnected of course) to see if the noise is present under load (lugging). I have never noticed it in the past, and I have pretty sensitive ears.
Above 1000 rpm, the engine produced no unusual sounds at light, moderate, or no load.
I removed the old water pump and bought a new water pump at the auto parts store, but the bearing seemed tight and had a grainy sound when spun by hand. The Suzuki dealer wanted almost $200 for a new OEM pump but I was able to order a new Japanese made AISIN pump online for $60, which was identical to the old water pump. When it arrived, the bearing seemed tight but smooth and quiet. This was installed onto the engine.
The almost new Continental timing belt on the car had zero wear and was re-used.The new Beck Arnley (GMB) timing belt tensioner had some stiction. It also had a slightly grainy feel when spun by hand. I compared it to the original tensioner, which had the same feel. (a sticking motion when slowly rotated). I had a spare used tensioner from my G16B Esteem engine, which had the same part number as the Cultus and it spun freely with no stiction and was completely silent when spun by hand. I installed this used tensioner on the car.
The new water pump, used tensioner, and timing belt was reinstalled, following factory service manual instructions, and the radiator refilled with new antifreeze. I torqued all bolts/nuts back to factory specs with my new inch-pound torque wrench. I left the timing belt cover off so I could observe the components after start up and use the stethoscope again if needed.
After about a 6 minute warm up and engine at base idle, no unusual noises were detected.
Conclusion: I think the timing belt tensioner and water pump bearing failure were responsible for producing the combined noises. It is amazing how useful the stethoscope is when trying to isolate noises! Thanks for the tips!
