Bone stock CRX Si.
The car seems to be driving ok, idles fine etc. But when I open it up on the highway the car will only go to 5k rpm and won't go any further. It just fades out. No CEL. Fresh distributor.

I already changed plugs, wires and changed out the ECU for another PM6.

I am clueless as to what it could be. If anyone has encountered this problem before or knows what it might be please let me know.

 

Poor timing?

 

you have maybe 1 theet off on your timing belt

 

Sounds like the fuel filter is getting clogged up. Whens the last time you replaced it?

 

I don't think it has been changed. I'll do that next!

And as for the timing, I didn't know the car would run with the timing off by a tooth. There is alot of engine clatter under the valve cover even after a fresh oil change. So there are a few "what ifs" but I don't wanna go crazy assuming stuff lol!

I'll check it more closely today and report back.

 

Do a valve lash adjustment if its noisy.

 

Will do!
Found something else odd just a few mins ago. There is a hissing coming from underneath the master cylinder. When I shut the engine off you can clearly hear it for 3-4 seconds then it goes away...hsssssssss. Leaking break booster? How would that effect the car?
The car brakes fine(or so I think).

 

a leaking brake booster will make the brakes feel firmer than normal, but as long as the valve on the firewall above the brake booster is there, it should not affect the engine idle.

Other things that can make noise around there:
1.) The PCV valve (change it or clean it if its more than a couple years old)
2.) A noisy t-belt tensioner - not fun to change, but easier than most cars unless you have an AC in the way to deal with. They make a noise like an old rollerskate wheel when the bearings get worn out.
3.) The Cold-air idle valve on the back of the intake manifold (near the brake booster with a small vac hose on it). On the A6, its an electronic valve that lets more air in to raise the idle when its first warming up in cold weather (based on IAT reading, from the little sensor on the #1 intake runner). The hose can get old and brittle - esp if it was ever splashed with brake fluid lol.

There's an old trick: Spray carb cleaner around those hoses on the back of the manifold and see if the engine suddenly revs up from the ingestion of carb fluid... that's a vacuum leak, but I dont know if its your power problem.