Idling problem/losing power

[1998gstspyder]

my car recenetly started having a problem with idling. It will just play around 300-700 rpm area, constantly moving around. I have not changed anything for months, so i dont know what has gone wrong. also when driving and I go wot, i feel like im losing power every now and then. my PCV valve is new, spark plugs are new. any ideas?

Mods...cone air intake, downpipe, boost controller, hks bov. thanks.

 

[oldman]

1. Boost gauge?
2. Vacuum reading at idle?
3. HKS recirculated?
4. How much boost is WOT?
5. Describe boost/rpm relations in detail?

 

[1998gstspyder]

1. Boost gauge?

yes. autometer

2. Vacuum reading at idle?

18-20 as usual.

3. HKS recirculated?

no, but it was never a problem before, so shudnt be now.

4. How much boost is WOT?

15-16, my mbc is at like 5 threads, which is no change in boost.

5. Describe boost/rpm relations in detail?

i dont know what you mean by this

 

[oldman]

i dont know what you mean by this

Don't worry about it, was trying to see if there was boost /vacuum leak.

A problem like this is very complex, process of elimination is usually the only way for us home made mechanics. Start with a leak test then check all the TB sensors. I find this chart very helpful. http://www.taboospeedshop.com/diagnostics.htm It's for 1Gs but same idea. Good luck.