DASC 318 Hesitating / Missing

[jorbon]

Set-up's been running great for many miles. Last couple of weeks or so, when I'm in 3rd, 4th or 5th at 2800 rpms or so and I push down hard to redline, there are intermittent 'flat spots' in the acceleration and even the engine noise--maybe 5 or 6 times from high 2000's to 6500 or so. It seems to do it much less in 1st and 2nd, but it is there...

No big backfire / detonation / etc noises, just a few completely dead spots in the curve for a split second each...

2800 ------------------------------------------- 6,500
Waaaaaa---aaaaaaaaaaaa--aaaaaaa-aaa-a--aaaaa

It doesn't do it at all if I take it through the same range more gently.

No CEL's.

Any thoughts? Fuel? Fuel pump? RRFPR? etc?

Spark? Coil? etc?

[NickG]

Check the fuel pressure while under load (ie, when the problem occurs). Also try putting a fresh set of plugs in it.

[Danny318]

Would be good to have a wideband o2 in there to know what you're a/f. You should really have one in this setup anyways.

[black318i]

Kind of sounds like detonation, maybe due to lack of fuel. I had to get my FMU rebuilt and it didn't even have that may miles on it.

[jorbon]

Check the fuel pressure while under load (ie, when the problem occurs). Also try putting a fresh set of plugs in it.

Tried the easiest route first- Plugs. Nick, if it hadn't come from you I would have ignored it as an unlikely fix... Well, you were right. New plugs and no more missing.

Thanks.