My 99 4.6 makes a weird noise on most start ups. It sounds like a bearing (possibly the idler). What has me confused is the rpm will jump 300-500 when this occurs. It is most common at aprox 1200-1300 rpm and it will attempt to climb up to 1500-1600 rpm if I would let it. I normally am going in a straight line or stopped. It can occur also after the engine has been run the normal 30 miles to work. Any ideas?

 

Have you read some of the threads in the engines section? Piston slap was a common problem on a lot of motors built at the windsor plant. I suggest checking out the piston slap summary posted by (I think) ml in the engines forum.



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-cm

 

I don't think there were many if any 4.6L's made at the Windsor plant in 99. Windsor is the only ones with any reported piston slap in a 4.6L. Check you VIN for the build location. If it is a Windsor 4.6 them maybe.

 

test

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Rich
1999.5 SVT Lightning - Red. Super Chip. K&N Filter. Viper Alarm w/remote start, clear corners, tow package, cd changer, cover, MTX Thunderform w/ 2 10" MTX 200w subs. 5-channel 300w Clarion amp., etc. Build #2755
stbtb@Tampabay.rr.com

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1999.5 Expedition XLT