16v flat spot, plus it feels like it is a turbo

[pentoman]

The more I drive my 1990 2.5 16v, the more I'm convinced there's something not quite right.

If you go full throttle from low rpm, it accelerates well, up to around 3000-4000 rpm, where it makes lots of noise but acceleration does not increase, until it hits the cam at ~4500 and takes off.

Additionally, and probably related, there's a definite throttle lag/poor response. I have to drive it like a turbo, putting your foot down early in anticipation of the power coming in about 1/2 - 3/4 second later. It's not a big deal but for what should certainly be a sharp normally aspirated engine is not right.

ideas?

I've had the mixture adjusted correctly (though I still have a high warm idle). The OVP is fine but I might replace it anyway because it may be causing me an ASD problem.

Russell


P.S. I have checked, nobody has put a turbo on it .