please help. strange electrical ticking

Hello, new member here. I have a 2014 toyota taco that starting making this weird electronic ticking when i let off the gas at highish speeds. It only does it when i let off after throttling. It started as barely noticeable, and now I here the click click click click click every time i take my foot off the gas pedal. I know it is a misfiring relay or something similar probably connected to my throttle body, I just dont know whick one. I tried to recreate the sound parked and could not. It is distinctly electronic sounding from in front of me while driving, not mechanical. If anyone can help me out, I just dumped a ton of money in this truck. I dont want to change the O2, mafs, throttle body, ect, without knowing thats the issue.

 

Relay like clicking??

 

yes.

 

It’s called chattering. A common cause is an extremely weak battery. But I don’t know how it could be caused by lifting after accelerating.

 

yeah... no. chattering is from a weak battery when you try to start it. definitely not it. thanks though

 

Ever heard a spark plug when it fires? It is more like snapping than clicking, but quite distinctive. Any chance it is that? Difficulty jumping the plug gap goes up as ambient pressure drops (i.e. vacuum rises). Highest vacuum occurs when you go from medium or high rpm to closed throttle. This is the time that problems in the ignition will cause sparks from the coil to be jumping to ground sources other than the plugs. When it jumps the gap outside of the cyl, you hear the clicking.

I can’t thinking of any relays that would have rapid clicking like that.

 

You might be on to something there. It could be. The clicking is rapid and seems to vary in intensity with the rpms but only when I immediately let off the gas. I bought this one from a dealer with the cat missing and a straight pipe weld, but they didnt space the 2nd bank O2 sensor to compinsate for the increase in temp. It has always thrown that code so I will check for ignition related codes tomorrow. I dont think its related. It has had no change in engine performance. I put in a new radiator, thermostat, and resealed the water pump recently. Are there any culprits that you might think could cause that?

 

I'd check the U-joints, that would be more plausible since it only makes noise when you let off the gas.

 

excessive spark plug gaps with failing coil boots or cracked porcelain. If the spark is successfully jumping to a ground, via spark plug or otherwise, it will not throw a code. Modern coils will report an inability to release a spark, but if it can release its energy it is assumed it went through the plug. This is NOT a common thing with coil over plug setups, but it does possibly explain the symptoms. Problem with cop setups is you can’t just spray water on things and watch the sparks.

given that this only happens on decel, you won’t notice a performance hit, as there is no combustion happening on decel as the ecu stops fuel delivery, but doesn’t stop spaking. I would consider replacing the plugs and the boots.

 

CEL on or any codes? How many miles on the truck? What all was done for work when you "dumped a ton of money" into the truck?

Id be leaning towards some sort of mechanical issue as well

 

That pretty much excludes the relay thing. I just can’t imagine many rpm related things that cause electrical clicking only on decel. Even mechanical noises that follow rpm are rarely only present on decel.

 

I doubt you'd be able to "hear" a spark related issue inside the cabin. If the plugs and/or coils were bad enough to misfire you'd be getting codes and rough running symptoms

Maybe the exhaust is rubbing on something. Like a heat shield or something

Check the belt drive system for a worn or fraying belt or loose pulleys. Is the fan hitting the shroud?

And yes, check the u-joints

 

ok i went to pull codes and surprise surprise, no codes. I guess it makes sense because there are no symptoms other than the very obvious clicking. I noticed that it is much more frequent at low speeds under 50 mph. It definitely clicks much more after immediately after I let off the gas, but it also does it at low speeds sometimes when pressing the gas. It has to be vacuum related or perhaps the butterfly valve in the throttle body is fluttering. It sounds like something trying to accuate or relay. Still stumped because the noise cannot be recreated in nuetral or park. fml.

 

I can't hear enough to tell..

 

im about to tape my phone under the hood

 

That doesn't sound like electrical clicking to me....

I'd be looking at exhaust system.

 

I think I heard it a couple times, I still say check the u-joints.

 

Yup.

I don't know how the exhaust is routed on a 2.7L, but Id check every joint and every heat shield. That whole video sounded like it was in a tin can haha

 

Doesn’t sound like relay chattering like I suspected. I hear a clicking but can’t say what it is.

You have an aftermarket exhaust? You think the exhaust rumbling is related to the clicks?