Ok so I had my water pump replaced today becuase it was shot. I had the same issue prior to getting it replaced keep in mind.

When my car is warm especially after spirited driving for a short time the thing seems to bogg down. I loose power and can't figure it out. The engine temp seems to be fine. I also replaced plugs coils and wires not to long ago also. Cleaned the MAF as well. I checked under the car to see if my cat was glowing but it seems fine. What could be wrong with it now? Could my exhaust be clogged?

It only happen when I drive it kind of hard with higher rpms. When just doing normal driving around town (not shifting very high) the thing is completly fine. I don't get it why it only happens when I drive it at higher rpms? Could it be that it is running too rich or something? I have a K&N intake and aftermarket exhaust. That's about it for mods.

2004 Manual 108,000 miles. Need some help here, I have no clue where to even begin.

 

Have you had a compression test done ever? It could very well be the cat. Is it stalling at all?

 

No, no stalls at all. Thing idles perfectly too (however I did just pull the battery cable to rest the fuel trims) to see if that will help. Plenty of stalling to come. No CEL's at all either. I just don't understand why it happen when I bring it to higher rpm's? Makes no sense to me. I in my garage now checking all my lines etc and notice nothing out of the ordinary or disconnected. Some other things to check for while i'm messing around in there?

 

Negative on the compression test. When it's cool or just milling around town I occasionaly give it some juice and it's fine. The power all seems to be there.

 

Well if the cat is clogged it will create power loss and it won't happen until the cat is good an hot. this can also ruin your motor so it's not something you want to let go for a while. I suggest removing the cat pipe and taking a look. If it's good, it should look like this:

http://www.flickr.com/photos/9krpmrx8/5391643523/

 

This scenario sounds like a clogged cat.

 

Awesome. I will try to check it out tomorrow. I'm going to take it out right now and see if resetting the fuel trims did anyhting other than **** me off from stalling. Any more advice would be helpful.

 

Could also be the fuel pump.

 

Ok so here's an update after resetting the fuel trims:

Obviously the thing wanted to stall out all the time as usual. I took it on this road by my house and beat the hell out of it and it seemed fine. No bogging / power loss at all. Once again checked for the glowing cat and nada. I never reset my fuel trims after cleaning the MAF, would that could cause it? I will drive it hard again tomorrow and see what it does and check the cat to see if the honeycomb is still there or busted up.

Fuel pump could be possible but wouldn't that make it happen all of the time or is that heat related also? I guess best case scenario would be fuel trims being out of wack = worst case my car gets lit on fire and I claim it on insurance

Any more suggestions?

 

Fuel pump will heat up when you start getting low on fuel. When you fill up again with fresh, it will start acting normal again.