drjewalton

Hello everyone. I have a 1984 Camaro Z28 with a 5 speed manual transmission. The car has only 33k miles. All original, runs like a champ.

BUT...there is a ticking noise that is heard within the car and seems to be coming from deep behind radio/heater controls. Here's the facts:

Noise occurs randomly - cold or hot engine - while driving AND sitting still.

Noise gets louder and softer, then will disappear and re-occur - sometimes within seconds to minutes, other times it may be a few days before it returns.

Noise is DIRECTLY related to RPM's - increases when engine is revved, whether driving or sitting in driveway motionless.

Noise is audible only from within vehicle -- hardly ever occurs below 700 RPM's so difficult to pinpoint outside with hood up.

Any thoughts? I've heard anything from exhaust leaks to sticky lifters to distributor rotor to you name it...but seems NO ONE (at least from what I can find) on this forum has ever posted that they RESOLVED this issue.

Once again, the car is 28 years old and otherwise mint....all exhaust bolts are tight, no apparent or obvious leaks. Engine has 33k original miles and has had penzoil synthetic its whole life with regularly scheduled changes.

I think what is so puzzling is that it is so random and disappears. To me, if it were a lifter or distributor or exhaust, it would occur more predictably and/or affect performance.

Please, please help!

Slow87

I don't know if it's the same noise, but I just solved a loud weird ticking noise on my car. Turns out a sensor wasn't plugged in all the way on my carb. I don't know if it is related to rmp's because I never revved it, but it was annoying. It took me hours to figure it out.

8t2 z-chev

heat riser valve rattle?

drjewalton

Here's another TGO member with same issue!

https://www.thirdgen.org/forums/tech...ind-radio.html

This TGO member also made a video with audio. My car does this exact same noise from same area. His car is 84 Camaro 305 automatic, mine is 84 Camaro 305 5 speed. Pay particular attention toward the end of the video because the noise just fades away while car is still running...mine does this too!

FtrSpeedy

I had a torque converter come loose and kinda did the same thing.

drjewalton

Thanks for the input but a torque converter is out of the question since mine is a 5 speed maual transmission.

I took a video from the inside of my car and put it on you tube as well...here's the link:


Notice the similarities in mine and the other TGO member's youtube video posted above in previous post:

1. Noise sounds same and coming from same area

2. In both instances, the noise just fades out and disappears while engine running

3. Both noises go faster with RPM's

(My car is a 5 speed...his is an automatic...both are 84 camaros)

Any other thoughts?

Characteristic of stuck lifter? (especially cold engine at start up...but would it occur randomly after driving for 60+ minutes? This sound reoccurs hot or cold engine)

Remedies without tearing engine apart?

saldav420

I'm kinda having the same problem with mine, but mine is an 88 iroc 350 tpi. I just got the heads rebuilt less than a month ago. I took a 2hr trip and when I parked it to unload stuff and turned it on again I heard knocking sound comming from what I'm guessing the lifters. Idk know if it's my oil thinning out or what. Also my service engine light came on with code 36.

Savage388

Strange I have a similar noise on my 86 ta only its a 383 5spd. The noise is plenty loud inside but I can't hear it from under the hood. It comes and goes as described only mine seems to be coming more from the passenger side.


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FtrSpeedy

Oh dam my bad

Vader

Are your spark plugs tight?

Does depressing the clutch change the noise?

Can you hear the noise from the engine compartment on the heads or block or under the vehicle at the clutch housing with a stethoscope (or using a tool as a stethoscope) ?

The noise seems to sound like an exhaust leak or valve train noise. An exhaust leak typically will fade as the engine warms and does not return until it has cooled. Valve train noise can get intermittent regardless of temperature, and you should be able to verify that by removing a rocker cover to inspect each train.

drjewalton

Spark plugs are tight.

Depressing clutch has no bearing on noise...occurs the same whether clutch is in or out.

Noise seem to be the loudest inside the car and under the car and much less noticeable from under the hood.

I've had a few folks tell me it could be a broken bolt from flywheel or even a cracked flywheel. Or a sheared rivet from pressure plate? I assure you this car is NOT hot rodded or drag raced and has never been ever since I'm second owner and know first owner very well. Unless its just a fluke, I really don't think the flywheel or pressure plate would just break. BUT....that seems to be the origin of the sound.
I plan to eventually raise the car and remove bell housing cover....then cold start it and see if I can "catch" it making the sound. (That's the whole trouble because it happens so random)

FireTurkey

just really random thought a power cable or ground arcing? hydro lines zap in the rain hard to know the sound of this so called noise


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FireTurkey

also rpm related possibly because your alternator spins and increases voltage and amperage


like I said random thought could have a nick in a harness



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FireTurkey

disregard everything I just wrote I saw the video


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Savage388

Same here except I just had a ring gear put on so I doubt that is the problem, however i have a bad throwout bearing not sure if that effects anything. From under the hood I cant hear any valve rattle, only a slight header leak, but its a very different sound than whats going on inside.

AutoRoc

iTrader: (1)

Plug left ear with left pointer finger.

Put the butt end if a LONG screwdriver against your right ear and touch it to different parts of the engine. ******* stethoscope... plugging your ears around any running engine cancels out a lot of the white noise surrounding the engine.

Goodluck!

dimented24x7

iTrader: (2)

Can you take a video from the engine compartment on start up? Sounds like something in the motor. Also, is it coming from down by the oil pan? Up top by the valve covers? Down in the clutch area?

Sounds a little deep to be a lifter, but if one is just plain plugged up, or has a broken return spring in it, they can hammer like that. I have aftermarket lifters that are entirely hydraulic, and have no return spring like a stock lifter to push the plunger up. When theyre flat, they sound a bit like your video, but not quite that loud.

Cal Trans

Whatever was the final word on this...because NOW I HAVE IT TOO. I have seen other sites say it is a gear (probably worn plastic) on the blend door from the ac/heater control. Seems common on domestic cars from what I have seen, but I have not found any pictures of it being fixed or stories of how it went. Anyone?

John in RI

iTrader: (167)

I just pulled my engine apart today in an attempt to rid myself of this "TICK"......




This motor is a "seemingly" low mile REMAN motor that still had good valve stem seals when I first opened it up. I had installed all new valve guide & seals, full roller rockers, and that's it.

I've probably had this TICK since the cars' been roadworthy a few months ago. Didn't notice it till after the 1st ( bad ) tranny was R/R and the first rear end was R/R. (first tranny only had 1st gear and 1st rear had a significant HUMmmmm ). The 'TICK" seems to come from directly behind the radio and is louder at some times than others. ( seems to be worst in the morning to me ) Pretty much non-existent @ idle,...... but increase RPM to a bit and I can hear it. Can hear about nothing from outside the car ( under hood or under car )

Due to the location of the 'TICK' I had always leaned toward this being a cracked flywheel. But; I had this flywheel in my hand and didn't notice a problem or would not have installed it. The fact that it doesn't seem to be a constant "TICK" also makes be look else-where for the problem. It's NOT exhaust, wheel, driveshaft, Speedo cable, rear end, brakes, suspension and I have already tried to completely re-adjust the roller rocker valve lash - WITH the car running - twice. I also checked to be sure the converter was tight to the flywheel.

Today I installed a new set of lifters, & the roller rockers and aftermarket pushrods were removed and replaced with stock parts. I've got to finish re-assembly this weekend and will report back with an update once I get the car engine running again.

I've never noticed a chance in the TICK while playing with the heater/blower controls. If the new Lifter don't fix the TICK,... I'll be checking the HVAC system next !


P.S. This car was a complete shell and EVERYTHING on the car had to be re-installed. This isn't an "original" car that's been fine forever and then I noticed a change..... I got this "TICK" while re-building.

John in RI

iTrader: (167)

Well - I've still got a the "TICK" !!

Guess I can remove Lifters, rods, and rockers from being possible culprits.

I was feeling that it was tranny related simply due to the location of the sound - but with T5 guys here reporting the SAME TICK,.... I just don't know where else to begine looking for this problem. Too "light"and too "fast" to be a Rod or Main bearing

The only thing I can think to try is to seperate the engine / tranny and start the engine to see if I can at least figure out if it's the tranny or the engine.


ANY thoughts??

OrangeBird

iTrader: (1)

Hi John ,

I am only asking cause I didn't see it mentioned , but if your distributor is the older style with the centrifugal advance , could weak springs be allowing the counterweights to rattle ?

drjewalton

Hello guys. I'm back and original thread starter. Apparently this is a fairly common problem with so many reporting the same thing. I STILL have the ticking myself but have more clues to what it may be.

Just last week I replaced all 8 spark plugs AND wires. The ticking still occurs BUT is less frequent and not as loud. Weird...makes me think it's something electrical or within the distributor? Alternator? I'm still running original alternator and computer controlled distributor. I think my next step is to replace the distributor with another CC distributor and see if anything resolves. I have heard these cars are notorious as well to have the pick up coil inside the distributor go out...but that would kill all spark.
Weird thing here (and others please chime in) is that performance is NO WAY affected by this irritating noise.

So...electrical? It HAS TO be somehow related to RPM's because it changes speed when engine is revved.

Still searching for an answer....

gt4373

My Car Is Similar To Yours And I Get The Same Ticking Sound But Only Occationaly And Only On Initial Start Up ,It Lasts For About 30-60 Seconds Then Stops I Think It May Be Related To The EFE System At Least In My Case,Seems Like Once My Engine Starts To Warm Up The Ticking Stops.

John in RI

iTrader: (167)

Ya,... mines sdtill doin' it.

This engine is using a vacuum advanced distributor and it's got TPI exhaust manifolds and Y-pipe. ( no heat riser. ) The distributor I've got is used - but I know it's history. I got it new and used it (with no issues) on my 355ci before that car was converter to FI. The thing still looked almost new when I pulled it last week - this re-build still has less than 1000 miles on it. Swapping distributors is a good idea just to be able to ewliminate 1 more part while trying to locate the problem. It spins with RPM and the sound is comming from "around" that area. I just don't have another one ATM to try !

Performance is not effected here either. No hesitation, no stumbling, no backfire, nothin' noticable in any way.

In my case it USUALLY doesn't TICK @ idle, I've got to increase the RPMS to about 1400 & higher to hear it. I can also hear it while driving the car. Much less due to road and wind,....... but I hear it.

drjewalton

Mine happens more often on a cold start while the engine is in fast idle (like the video I posted above) but will also occur randomly after driving a awhile. Sometimes I can go days and not hear it. Other times it's every where I go. It is ALWAYS intermittent- comes and goes. Mine too happens above 1200-1400 RPM, never below -which makes it more difficult to try to diagnose with the "stethoscope" method since it goes away by the time I park and pop the hood. Only if I'm lucky enough to have it happen long enough on cold start up could I really try this method.

I have not considered the EFE system and will look into it too.

I would love to be able to put this issue to rest, as I'm sure would all of you so if anyone finds a resolution, please post!

drjewalton

After reviewing other threads on this issue, there were other folks saying to check the heat riser on passenger side for rattle. Don't quite get how it would rattle exact with rpm's but something loose would be a good explanation for the randomness and the intermittent occurrence and that it doesn't affect performance.

I'm off work this week so hopefully I can get time to assess it again!

John in RI

iTrader: (167)

Just a quick update to keep track of things --->

My 86Z is using TPI Exhaust Manifolds with a spacer in place of the EFE heat riser used in Carb cars. ( My TICK can't be that. )

I ran my 86 till I could hear the TICK and then messed with the HVAC system. The TICK was unchanged regardless of the air delivery Mode, Temperature or Blower speed. The vacuum line was then disconnected @ the intake and there was still no change.

As my luck runs,...... The Radio in my 86 died a couple days ago. While it was being replaced I listened to the TICK thru the empty hole in the console and it honestly seems to be coming from the tranny tunnel. It even seemed to get a bit louder when I removed the rubber grommet on the floor the shift cable runs thru. After hearing the sound in that way I am just about convinced that my TICK is Flywheel, Torque Converter, or Tranny related.

* I know it's been reported on STICK CARS - that's the ONLY reason I've done some of the previous testing and replaced some of the parts that were changed before focusing on the automatic tranny. ( flywheel to TC bolts HAVE been checked )

I'm still going to probably swap the distributor when possible simply to eliminate another possibly suspect part as a possible cause,.... just have higher priorities ATM.

Keep updating as you progress thru your investigation - We'll find it sooner or later !!

sonjaab

Another thought is the hvac fan motor!

Remember in these cars with a/c the fan motor runs ALL the time even in the off
position! This is a throwback/hybrid from the early GM "astro-ventilation" systems
started in the late 60s GM cars.

Try unplugging the hvac fan motor power and see if the noise stops.............

John in RI

iTrader: (167)

In these cars the air delivery "mode" will default to the floor vents when not actively being used - or "turned on". It feels like the system is blowing hot air at you even when it's off. (This is particularly true in pre-87 cars without the AC diverter valve) But; the blower motor itself doesn't spin if the controller is switched to OFF position.

I WISH this was a HVAC problem !!

sonjaab

John.........In my bone stock 84 with a/c the fan motor is running all the time
when the ingnition is on!
No matter where the control is placed. The ticking drove me crazy and my GM
tech bud told me that the noise is from the fan and typical of these year GMs with
a/c.

Disconnecting the fan power to test confirmed this.................

John in RI

iTrader: (167)

Just to keep the details accurate..... my 86 had a plate riveted over the heater box area. I rebuilt the car using an AC harness, blower relay,resistors and controller. The box itself is a AC delete box and an AC delete blower motor.


I'd question that operation,..... check your relay; if the controller is OFF the relay should not be sending power to the blower motor.

By the way: don't think for a second that I will not be check into it by unplugging my blower motor !!

sonjaab

Ahhhhhhhhh...................

So you car is all cobbled up then? Switch this, changed that, removed this...........

Sorry I thought you had a bone stock car that had a ticking noise.

Ignore all my posts then...............

BTW: My 94 Buick century winter rat with a/c and bone stock the fan in this
one runs all the time also...........tick, tick, tick although quieter than the Zs fan.

John in RI

iTrader: (167)

I believe this is a fuel system problem.


I got the tranny separated from the engine today and was prepared to swap the Torque Converter and the Flywheel. I ran the engine while they were apart and still heard the TICK. With the help of someone bumping the throttle, I was able to get under the car and listen. At times it seemed as if I could hear the tick from the back of the car. I found that the tick was "in rhythm" with the feeling coming from the main fuel line.

When the TICK was present I could feel it at the back of the line before the rear tire, at the tranny 'hump", and on the pass side hard line. I could also feel the short rubber line ( from the hard line to the pump ) 'pulse' in rhythm with the TICK.

I don't know if it's due to the tank pick-up, the fuel pump, the Fuel Pump Rod, or if there's a crimp or blockage in the line somewhere, but after today I'm almost positive that it's in the fuel system. Hell; even though I've got several plastic zip-ties here and there,.....I still can't even rule out a vibration problem.

The reason the TICK seems to be originating behind the radio is because it is. The Carb fuel lines run from side to side around the tranny tunnel in that spot. I was unable to get rid of the sound by moving/altering the position of the lines in that area. My fuel lines are stock from the pass frame rail to the back of the car, but the short length from the pick-up to the hard line WAS extended a few inches. I can feel it in the FEED line FROM the tank, could not feel it in the RETURN line TO the tank. Once I get some 3/8th fuel line I'll do a bit of testing to see if I can further isolate the problem.

drjewalton

You may be on to something. My ticking noise didn't start til weeks after I replaced the mechanical fuel pump. Coinciding with RPMs makes sense with the push rod for the pump. I'll have to investigate this on mine as well!

On another note.... I'm in the process of converting mine to NON-cc carburetor and NON-cc distributor. I will report back (soon hopefully) if the "tick" still exists after the carb/distributor switch. If it does still exist, I'll replace the fuel pump and closely inspect the push rod during that process.

We're close !

John in RI

iTrader: (167)

Cheap replacement fuel pump.


This thing has less than 700 miles on it; The pump lever is a little loose on it's pins,... but the real problem is the internal spring circled in the pic.




On the new pump the lever is firm and the spring is stationary at all times. The used pump's spring is "short" and will travel UP/DOWN just a little bit with the lever action. ( TICK - TICK - TICK ! )


Installed a new Fuel Pump and the short section of 3/8" line from the hardline to the pump. ran the car for about 4 minutes then took a 3-4 mile ride......... No TICK.

drjewalton

Hallelujah! Praise The Lord! Finally some resolution! I can safely rule out distributor since I placed a new distributor and non-cc carb on mine.....still ticks! But the car runs SO MUCH better!

New fuel pump is next on the agenda as I'm sure mine is due to same thing. I replaced the fuel pump on mine about a year and a half ago with an autozone cheapy and have had the ticking ever since.

What brand/part number pump did you use?

I'm so freakin excited to replace this and put an end to the ticking!

Thanks for all your hard work and investigation into this issue. You've made my day!

John in RI

iTrader: (167)

I've got the same FP you do,.... $24 unit from AutoZone. The new one I just installed was the same exact unit so I'm not expecting it to last very long.

As soon as this one starts ticking I'll pull a 15Y/O Edelbrock FP out of the bottom of a storage bin in my garage and will use that with a 3-way fuel filter.


I'm Soooo glad to finaly KNOW what was causing that TICK !!