1996 12v 4x4 ticking noise during idle

[Iron Duke II]

I have a 1996 12V 2500 4x4 with 130k mi. It runs well, but something from the driver side of the engine bay makes an ticking sound when it idles. It does not appear to be a knocking noise, but does sound like a piece of tin that is being pinged, when i stand beside the truck while it is running. Any guidance is appreciated!

 

[Wiredawg]

Could be the pump. Get an engine stethoscope or long screw driver to isolate where the sound coming from. I had 1st and 2nd gen trucks that big part of engine noise came from the pump. If using a long screw driver, be sure to hold the handle to your ear and not the business end of it.

Cheers, Ron

 

[GrantP]

More than likely the lift pump. My 97 did it but I never had any problems. Drive on...

 

[BigPapa]

I’d also put money on the lift pump. I found mine does it primarily when the fuel filter needs changing. It’s never been a problem. I’m on my 2nd lift pump in just over 500K. I replace the original at 150K because of the ticking. That’s the pump that’s been on there for the past 350K. It ticks, too. Drive on.

-Scott

 

[crabman]

Redneck stethoscope.
You can tape some type of plastic funnel or 2 liter bottle with bottom cut off to the handle of the screwdriver to amplify the sound.

 

[Wiredawg]

Redneck stethoscope.
You can tape some type of plastic funnel or 2 liter bottle with bottom cut off to the handle of the screwdriver to amplify the sound.

One more important step....you may have to stick you finger in your other ear so you can hear yourself think and hear any noises in your redneck scope. Half funny, all true.

Ron

 

[Signal73]

Feel the return line, if it pulsates along with the tick you know it’s the lift pump. And it is normal.

 

[GAmes]

I don't know about it being normal. Mine doesn't tick. I replaced the only one I have had that did tick (the original) and started replacing them at 300,000 mile intervals as preventative maintenance. My understanding is that the return spring for the push rod is losing it's tension and allowing the rod to lose contact with the cam lobe. The tick is when it impacts the cam lobe. The constant beating on the lobe can not possibly be good for the cam. My original lasted much longer than 130k miles though and it ticked louder at higher rpm, not just at idle. It is a $115 part from Genos. If that is the noise I recommend you replace it.