So if you look at my other posts youll see what ive been working on. with fluctuating performance issues. with the bolt on mods you'd think my car would perform better. sometimes it does sometimes it doesn't. I dont wanna seem like im just posting the same thing over and over, the threads start, conversations start, i try the suggestions and the threads die off. But the problem isnt solved.

I love how my car feels when i dont drive it for a day then I take it out, somethings had time to cool down thats making a huge difference in throttle response. When i take it out the second time, that response is gone.

my last attempt was a tps calibration. it didnt do a whole lot. so now i gotta find something else. The issue started with the f23 manifold swap. that shouldve added power. im wondering if the iacv got damaged in the process. the idle is a little rough and varies randomly when i go on a drive. it may be at 800 rpm at a light and it could be at 700 at the next light. But im not getting the tell tale signs of a bad iacv.
I'm also considering cutting off my muffler and buying a flowmaster. I have an ebay exhaust (yes I know, I know) it was more of an experiment, and has held out well, but I'm wondering if I need more backpressure.
I also have a 3" intake pipe. That discussion has varied. Should a revert to the stock 2.5"?
Those and maybe another egr cleaning are all I can think of. Still, no CEL's, no obviously peculiar ECU data thats saying anything.

Anyone? What should I start with?

 

Dare I suggest it? How about returning it to stock?

 

Runs good cold and bad hot...that would frustrate the heck out of me. I hate intermittent problems. I'm not a professional tech so I tend to fall back on the FSM when I run into stuff like this. The FSM diagonostics procedures are systematic. Looking at the "Loss of Performance" line, in order of probability:

1. Fuel supply
2. TPS
3. MAP; VTEC solenoid valve; fuel injector; intake air; other emission control

The TPS is done obviously, but I haven't combed through your other posts. What's the fuel pressure? MAP output voltage in spec?

There are quite a few F23 manifolds on F22B1s that run fine. You just have to find the problem.

 

@shipo: ive thought about that a few times, and eventually i will when i wanna sell it but for now i wanna learn how to modify a car starting with these basics. so with this problem, i know people have done all the same things and have gotten good results. I'm trying to get that. eventually ill switch almost everything back though. its nothing a day or two worth of work wouldnt fix.

Thanks for the sympathy roader. Thats a good way of putting it simply too. good cold, bad hot. I have the FSM and I look up the performance issues and then double check them with things online, but I generally dont see anything that matches the symptoms exactly.

Im pretty sure i changed the map sensor with the tps. I just put on a whole new tb with the sensors attached.

VTEC solenoid valve would only cause issues in VTEC

fuel injectors would throw a code right?

Intake, im still wondering about the high temp readings i got from the IAT sensor in the upper manifold. While the air going in would be in the 30s. it would get up to 100 degrees in the IM. That brought me back to the EGR issue as EGR gases would be hotter. But not that hot unless there was an issue with something.

And then theres always the vacuum leak- with no lean code, so I dont know about that still.

 

Speaking (errr, writing) frankly, I am someone who looks upon the claims folks make regarding the improvements resulting from bolt on aftermarket additions with considerable skepticism. Unless said aftermarket product is a component of a forced induction system, or say a set of Acura cam shafts, then any minor improvements in top-end power will typically be met similar reductions in mid-range torque and engine responsiveness.

 

Yeah, i have looked into the sacrifices made between high and low end power, thing about my mods is that I have gotten the claimed gains but they have gone, not with ECU adaption either because even after resetting the ECU, either electronically or by just unplugging the battery for an hour, I dont get the back exactly. Its all intermittent. I drive my car and the throttle is nice, smooth, and responses. Other times it feels loose and my car feels like it has a little 1.6L in it.

 

You won't find "exactly" in the FSM. "Loss of Performance" is as specific as it gets.

Was the plenum removed/EGR port cleaned out before the manifold was swapped?

6thgenaccord(dot)com/forums/showthread.php?p=398447

 

Yeah, I worked on that thing for a week or two cleaning and painting it before installing it. You can see it in my pics.
I'm wondering if the EGR itself may have anything to do with it. But all I can really piece together is that its when something gets hot enough and the IAT sensor readings where its located on the f23 manifold read up to 70 degrees higher than the air just before the TB. That makes me think the EGR, but apparently EGR gases arent hot enough to cause that. I'm not sure where they're cooled off before entering the IM. Plus the EGR is on the other side.

Then again... bad egr would explain my coolant temp always being at 205 right? My car runs hot, even in this weather. it should be at 190 I think.

could be the CAI even... theres no IAR so the air flow may be disrupted during stop and go traffic thus reducing my volumetric efficiency- thats cancelled out by the cool air going in but once everything warms up I start to lose power. on the highway my car accelerates pretty well. this is all city driving.

again... no CEL. I do have data if you can spot irregularities.

 

yeah i think ima revert partially to stock air intake and see what that does. it appears removing the IAR could have caused damage to my low end power. it may or may not correlate to the hot vs cold performance. But ima see. I just need the intake tube from a junk yard really.

 

I can only see the outside of the manifold in the pics. The internal port from the bottom of the plenum to the EGR valve was almost completely constricted on my 116K F23. That port is open and clean?