Stumble during rev, idle weirdness

[OrLackThereof]

Just wondering what you guys think of this. When I free-rev my car, it always stumbles for a second before the rpms go up. If I roll on the throttle, it's fine...but a sharp jump and it sounds like it misfires.

The idle will randomly get extra choppy too, to the point that the entire car is shaking from the engine shaking, but I suspect that's just the cam acting weird. The main problem is, when I rev it...it will come down extremely slowly, and it will hang at around 1300, then drop to 1100 and hang there, then FINALLY drop back to idle.

The car lacks a little bit of low-end, but that's due to the cam and bad tranny I think. There are no flat-spots in the acceleration and the car runs awesome, besides for these few problems.

Does this sound like a problem with the TPS? It's new, but I don't know if it's been calibrated properly. IAC valve is also new. I checked for vacuum leaks today by spraying some TB cleaner around, but nothing happened. My idle-vacuum is horrific though...for being such a mild cam, I was surprised I only pull around 12 hg's of vacuum.

Any help you guys can offer is appreciated. I've dealt with these little things for months now and they're starting to get on my nerves.

 

[noslow5_0]

you may have a vacum leak.... i just hid all the wires on my passenger side strut tower, and when i pulled all the vacum realated stuff out (all were hooked up, but capped off if you get what im sayin) and was basically the cause of my weird idle... I did the whole carb and tb cleaner thing and it didnt recognize.....

 

[jerry beach]

Hook a vacuum guage to it and start capping crap off. I have done them all at one time, or one at a time. If you see the vac. rise, there is your leak. I have not done it but heard it from the jrichker on here you can check the manifold gaskets for vac. leaks with an old oil can. He said its messy, but safer than carb cleaner and it works. I trust him, though I dont know him personally.

 

[OrLackThereof]

I've checked through a lot of the hoses and can't find any leaks...but I might try what you suggested. My brakes are on the mushy side, which tells me I don't have enough vacuum. Is it possible that there is a vacuum leak INTERNALLY, in the power booster? Like through a diaphragm or something?