SR22/G2 surging RPM Problem

I fly a 2005 SR22/G2 that has around 950 hrs. The past few times I’ve been up I’ve noticed the engine is surging slightly. I typically fly for two to three hours and have been in this plane for over seven hundred hours. I’ve become very intune with the sounds it produces. Today we flew from Birmingham Al. up to Crawfordsville In. at 8000 Ft. All the way there and back she was surging .The RPM,s we’re bouncing back and forth between 2460 and 2480. The EGT were also fluxuating between -05 and +25. My A&P said it sounded like the govenor on the variable speed prop.Has any one else dealt with a similiar issue.If so please let me know what might be causing the problem. My e-mail is nicholsind@aol.com if you need it . Thanks,

Ours was a bad fuel flow sensor. Insude is a small impeller that was starting and stopping…Ed

What was the Fuel Pressure doing doing this time? A prop gov could do that but your EGT is perhaps telling a different story. EGT’s would not not vary that much simply because your prop gov was surging a tiny 20 RPMS.

If you have EMax download that flight and look at FF. Good luck.

I agree with Roger. This sounds like a fuel flow issue and may be related to the fuel flow sensor.

Thanks, for the help. I spoke with a tech down at montgomery aviation and he said it sounded like a fuel issue to him also . He said he would do some research for the AD listings to see if my serial number was on the list (1425) To replace a fuel gasket. I dont think it is or I would have already done it ,but well see.

I think the service tech called it a gascolater. He sugested keeping an eye on the fuel flow.

The G3 had a gascolator SB but no previous G2 and G1 planes did not.

On your next flight lean the a/c and then in cruise watch the fuel flow. It should move up and down about .5 gal/hr. You will also feel the surge in the engine in real time…Ed

Thanks Guys . The next time I 'll try your sugestions , and see what happens.I wonder about how much is a fuel sensor , and can my tech change it out ?

Don’t know what it costs, but any A&P can replace it.

I think the part was about $285.00 and it took about 1 hour labor…Ed

Thanks Ed ! We’ll see what happens …