RPM bump on start up

[RHulette]

I've been searching the threads looking for a similar problem, but no dice - I figured I'd throw it out to you guys.

99 Quadcab, 2wd, 256k miles. Runs like a top, no issues, FASS pump with Glacier two stage filter. everything else is stock.

I've noticed just recently on start up that I get a momentary 1 second bump up in RPM to around 1000, then it settles back down to 800. More pronounced in the am after sitting all night. If I start it after just a couple of hours, it's less pronounced.

Just thinking - could I have a slightly leaky injector?
I've been monitoring the oil, giving a sniff for #2, but it's fine.

Anyone seen this before?

Thanks,
Randy

 

[GAmes]

You will never smell fuel dilution in the oil. Send a sample in for analysis.

 

[SAndreasen]

It takes a quite a bit of fuel in the oil to smell it . I agree send a sample Off

 

[RHulette]

Thanks, I'll grab a sample and see what it says.