Rattleing at idle RPM's 4.0 OHV

[whj812]

Hello,
I have a question about my X. I have a 99 4.0 OHV. It Idles anywhere from 900-1000RPM's normal; but at idle speeds it sounds like the valves are rattling or something. When I give it gas and it gets to about 1400RPM's it goes away. Does anyone know what this could be? My theory is Gas. I put 93 in it, but i bought it somewhere that I usually dont buy gas from. I am just trying to prevent a major engine overhaul!

 

[TPLYNCH]

Sounds like marbles in a tin can??? If so, that is normal for the OHV in '98 & '99. Mine does it. Has to do with a redesign of the wrist pins to supposedly improve exhaust gas #'s. Ford claims it won't harm engine, but I believe some Ranger owners were able to fight to get new engines.

 

[whj812]

Yea man sounds just like that! It kinda freaked me out, because i just got the truck. I hope that what ford says is true! Oh well! Thanks alot man.

 

[Alec]

why do you use 93 octane? Unless you have a chip and/or serious power mods, you shouldn't use it. 89 is ok, but 93 is total overkill. Also, 900 is a bit high for idle. I'd try resetting the computer to lower the idle a bit. Good luck!

 

[whj812]

Also I forgot to add, that the whole rattle sound didnt occur until I changed the oil in it. I used 5w30, what the owners manual said. My friend told me I should use 10w30. Would this help??????????????

 

[whj812]

OK! Update! I got my friend to look at it, he is a mechanic. He said it sounded like the timing chain! Is it normal for a 4.0 ohv to lose a timing chain at 70K. I had a ranger 2.3 with 170K on it and it still is running perfect. Uses a little bit of oil!!!! OH WELL.....can anyone help me?? Thanks guys

 

[231Saleen]

I think you mean timing belt. When i push my truck i get that marble/tin cup sound between shifts. I thought it had somehting to do with the timeing. But i guess im wrong. At idle you can hear the stress on my engine from the supercharger. Its very annoying.

 

[TPLYNCH]

What kind of oil filter did you use. That makes a difference too, especially if it's a FRAM. Read the Oil Filter study at the top of the General Explorations forum page for more info.

P.S. 5W-30 is the recommended oil.....

 

[whj812]

Yea I did use a FRAM filter. It was the only one that Checker had beside Penzoil.....the checker over here sux man!!