engine knock//who's there!!

[usedcars]

I have a 2000 Ford ranger 2WD 3.0-V6 Ext cab PU. I have a cold start knock that goes away when warmed up at idle but returns once warm and under acceleration, It sounds to me like a lifter, Do these trucks have any common valve train ( lifter pushrod or rocker arm problems) The truck has 100 K miles on it. I have tried carbon cleaner through the fuel system and atf in the oil. It runs strong no misfire or loss of oil pressure ( at least according to the gauge) Oil level is now abount a pint overfull after adding Atf, It looks as though the oil fill area is clean which would make me think they have serviced the vehicle on regular basis. I have not removed the valve covers at the time of this posting.

 

[adsm08]

Well I wouldn't run it that overfull for long.

Found a Service Bulletin for your truck for spark knock. Says to drain tank, add 2 gallons of 94 octane, and see if it goes away. If it does, you replace the coil pack and the PCM.

 

[usedcars]

Would it be normal to hear spark knock with no load and just raising the rpm's while in park?

 

[adsm08]

Could be.

Spark knock generally sounds more like a rattling. Almost like someone but a bunch of silverware in a leather bag and is shaking it around.

Engine knock usually sounds like something hitting something.

 

[usedcars]

Drained the oil and changed the oil Filter// Motorcraft filter and Pennzoil 5W30 motor oil, Also used a stethoscope to listen and try to pinpoint the noise, I can hear the ticking at steady rpm's and as you rev the engine and release the throttle and listen to the rpm's drop. You can hear it very well by placing the stethoscope on the alternator, With or without the acc. drive belt in place. Does this engine have a balance shaft? Or are they prone to chain tensioner problems?

Thanks for your help