Ticking/knocking under heavy acceleration

I agree, I don't think the ticking noise is anything major. Like I said, it's been happening for a while with no increase or decrease in severity and with no impact on driveability whatsoever. If you were deaf, you would never know. The best way I can describe the actual noise, for future searches on this issue, it is very similar to the "tings" you get when the aluminum block is cooling off after you shutdown, except louder, but almost an identical noise. It's not rod knock and shame on M4rk for insinuating such a thing and making me get nausea.

As far as the magnaflow cat situation goes I went back and reread your previous thread you linked about it and am wondering if my leak has progressed and if so, why. Nothing seemed out of the ordinary for me when it was first installed sound wise, at least according when I responded to you but now there is definitely one. Makes me wonder what my slightly hillbillyish friends that installed the parts in their shop for me did. Like I said, he mentioned new bolts but I still have the same flanges. Maybe it was a best they could do fix without replacing my flanges. I too have since lowered and scraped a few times, which can't help this situation. I did take it to an exhaust shop later and they did inspect some of the clamps and welded a few spots, they said it was leaking too. The next day I was going to return because not much had changed but the night prior I flashed my ECU with a torrie tune and I suppose because of the timing changes the raspy leak sound was reduced a lot and with the winter approaching I just put the issue aside.

I'll probably take mine back next week and fill them in with everything I learned here. Hopefully I can get this fixed before summer really hits.
 
Upstairs Chris said:
... The best way I can describe the actual noise, for future searches on this issue, it is very similar to the "tings" you get when the aluminum block is cooling off after you shutdown, except louder, but almost an identical noise. ...
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Are you sure it's not just a little spark knock. Even with 93 octane gasoline, a tiny bit of knock (ping) under medium load seems to be normal for these engines.
 
Chris, According to my mechanic, it can be done properly using the magnaflow flanges and new bolts. According to my mechanic, with new bolts, you do not need to swap the flanges...

Joe, I would agree but I had never heard it before and I've always used 91/92 octane for the last 5+ years of owning the car. My noise is a bit louder than just a "ping." I don't know enough about spark knock, but come to think of it, my noise seemed to start shortly after installing NGK Laser Iridium Spark Plugs and new Motorcraft coils...I did so shortly after installing the cats as I didn't want old coils/plugs dumping a bunch of crap into my cats.
 
joegr said:
Are you sure it's not just a little spark knock. Even with 93 octane gasoline, a tiny bit of knock (ping) under medium load seems to be normal for these engines.
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Honestly, it probably is. I am familiar with spark knock in the sense that I've read about it but I've never owned a vehicle that did it enough for me to notice, so in practice, it's new to me. Also, if some is normal about how much and why. Everything I've ever read about spark knock, pinging, etc etc has described it as the bane of my engines existence.

Edit: Despite having this sound for a while now, what drove me to comment on it today was last week I reflashed the ECU with the most aggressive Torrie tune I had. He gave me three tunes, MPG, Performance, and Performance +2, the +2 adds two degrees of timing according to Torrie. Before anyone comments, yes I know that is not the tune file names most people got but that's what the man gave me. Anyway, I suspect the "+" symbol isn't recognized by the tuner and when I went to flash my ECU for the first time it only showed the MPG and Performance tunes. At the time I went with performance and I enjoyed it and drove it like that for some time. Well last week out of boredom, I reprogrammed the xcal and re flashed to the Performance +2 file which did show up after I omitted the "+" symbol, and that is when I really started to notice this noise. Today, I just reflashed back down to the Performance tune without the additional 2 degrees of timing and it's much harder to get the sound to come back like it was. So yes, I'd say what I hear is spark knock.
 
Interesting reads but let's not forget possible fuel injectors, plugs and/or timing chain slop.
I know when I'm going through drivethroughs up against a wall, I'm always cursing the sound that's magnified coming from underneath. Also that loose CAT sound like you guys are describing.

I'm looking for a slight tick under load, which is not there during idle. I can hear it underhood when I open the throttle body valve as I'm listening nearby, mine seems near the front of the passenger side VC, dreading the secondary timing chain tensioners on both side might be due but not ruling out the CAT sounds or even plugs or injectors.

I had it before and on an oil change I thought it went away for a little while. I'll be chasing it this summer to see it to it's resolvement.

I'm due for some fresh CATs also but I can see myself straight piping it instead. They don't do exhaust sniff tests around here anymore, it's all plug into OBD and read onboard sensors, so I'd just have to make sure it's zeroed out at the sensors somehow. Still will be looking into seeing if this is the brightest resolution or not.

Damn little ticking noise under load! I HATE IT, I HATE IT!!!
 
hehehe, band-aid temporary solution!
 
BigRigLS said:
Sooooo looking forward to see if my 'slight' ticking under load will stop again on the next oil change.

~ still in storage though.
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I've had the ticking noise since I bought my LS. Over 160,000 kms later, and very aggressive driving, still fine. Not sure if that helps at all lol

A good way to find out, is install that Tune and punch it. If you hear "Boom" followed by no engine power, well we know something was wrong! =D :D
 
Have you looked into a top engine cleaning? GM has some stuff called Top Engine Cleaner that does an amazing job of getting any carbon and crap off the inside of the engine. Carbon buildup can occur regardless of how clean the fuel might be, and this carbon causes the engine to retain more heat in the combustion chamber. This can cause the fuel to fire off a little too soon, which can cause the noise.

The way this stuff works is you pour it into the intake while the engine is running (you have to get creative when the throttle plate is mounted sideways) slowly while someone keeps the engine running with the fuel pedal. When you've slowly poured 2/3 of the bottle in, you then dump the last third in until the engine dies. After the engine dies, you wait 15-20 minutes, then start and drive the car for a few miles.

How effective is it? It works so well it's illegal in California (can't have anything that works there). If the engine is carboned up, then when you crank it up again the car will spit out huge gobs of horribly thick, clingy smoke that even the winds of Oklahoma has a hard time dispersing it, and it smells terrible so you won't want to do it at home. Of course, if the smoke doesn't come then it's likely that this isn't the problem but it wouldn't hurt to clean the inside of the engine. The last engine I used it on had a slight pinging problem, and after the cleaning the pinging problem was gone and the engine ran smoother.

Last time I bought this stuff at the dealer it was 12 bucks a bottle, and it only has to be done every few years. No idea if they still make it even, it's been so long since I used it but if your local Chevy dealer has it and you can figure a way to get it into the intake it might solve your problem.
 
Sounds interesting and I did some searching - yes, you can still buy it. Based on my limited searching, lots of guys seem to like it and say it's a "heavy duty" version of seafoam. I've never seafoamed a car and to be quite honest, dumping all kinds of stuff into a motor scares me no matter how many people swear by the stuff. It's also recommended to change the oil and spark plugs afterwards and some people claim it fouls oxygen sensors.

Obviously GM would use this stuff in a dealer so (if done properly) probably can't screw much up, but does anyone know if Ford offers something similar?

I generally dump some Techron into my gas every other oil change and have tried some different filters (PureOne, Wix, Motorcraft) as well as 5W20 Mobil 1 and 0W20 Mobil 1 but the "ticking" is still there. Doesn't seem to impact performance as I was just out doing some spirited driving :) and the car still runs strong with 150,000 miles.


I have noticed that occasionally when moderately accelerating around 40 (trying to get to 50) my rpms hop up and down like I'm tapping the gas. If I push the gas a little harder (accelerate quicker), the rpm hopping goes away. I wonder if that's gunky intake or a trans problem or a fuel pump problem or something else. I was hoping it was a fuel filter, but I recently changed that and still have the symptom once or twice a week while driving.
 
When I did it the O2s weren't fouled, but I can see it doing so if the engine is really, really dirty. It is a really heavy duty cleaning. No idea if Ford sells anything similar, but it won't hurt to use the GM cleaner in your car.

Do you hear this under idle? If so, you can try listening to various parts of the engine with a length of heater hose, or with an automotive stethoscope if you have one. Even if you can't hear the noise at idle, you might still be able to hear the noise when it's concentrated in the hose/stethoscope. I know that injectors fire loud enough for even me to hear them when I use the heater hose to listen around on an engine.

The RPMs jumping under light throttle between 40-50 sounds to me like the torque converter is locking and unlocking, and from what I've read her the torque converter is a problem point for the LS. Try doing it with the brake pedal depressed enough to light the brake lights and see if you have the problem. The computer senses when the brakes are on via a switch on the brake pedal (at least on every other car in the world, who knows how Lincoln did it with the LS) and will unlock the torque converter. If the torque converter is causing the bouncing RPM under light throttle between 40-50, then you should not see the problem with the brake pedal on.
 
I had the same problem with my 04 Town Car. I thought it was a lifter. My mechanic is a 12 year Ford mechanic with his own garage. He looked at the engine, put a stethescope on it and found it was one of the fuel injectors. Told me to put a quart of Mystery oil in with my next change and it would go away. I took the car home and added around 1/5 of a quart of mystery oil. Noise went away within a few minutes! I looked all over the web but couldn't find this simple "cure", all said change the injector. It wouldn't hurt to try it, and you've probably got Mystery Oil on your garage shelf anyway. Be sure to let us all know.
 
Gescojoe said:
.... found it was one of the fuel injectors. Told me to put a quart of Mystery oil in with my next change and it would go away. ...
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Wait. You are claiming that adding an additive to the oil in the crankcase somehow fixed a noisy fuel injector? You do know that engine oil never comes close to any of the fuel injectors? I could see the additive might do something for hydraulic lifters (which the 3.9 does not have). I might even go along with it working on the injector, if you poured it into the gas tank, but it doesn't sound like that's what you did.
 
I'm going to assume that he put in in the gas tank, and it works very well when poured into the fuel tank. I've been using it as a fuel system cleaner for a couple of decades now, although I use half a quart to a quart depending on the size of the tank. On the LS I use half a quart.
 
Telco said:
I'm going to assume that he put in in the gas tank, and it works very well when poured into the fuel tank. I've been using it as a fuel system cleaner for a couple of decades now, although I use half a quart to a quart depending on the size of the tank. On the LS I use half a quart.
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Surely he did, but saying "Told me to put a quart of Mystery oil in with my next change" sure makes it sound like it went in the oil.
 
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