H23 intake manifold problems

[jumpman83]

I don't know what's going on, I put my new intake manifold on (the vacuum actuator for the IAB's were open) and my idle went to hell. After messing with all the gaskets I figured out it was because the throttle body didn't come with a fast idle valve. I blocked off the ports and it began to idle properly. So, I started driving around to check out the power gain, and noticed the thing sounded like the bastard child of a lawnmower and a boxer engine, and that the power gain wasn't there... I actually lost power. A lot of power... Within a minute it threw a code. I drove to my school where I could check it out, and checked the code. 22, which doesn't exist, and yes I double checked it was 22. I didn't know 22 didn't exist at the time, just that I wasn't familiar with it, and went around the car checking stuff out. The exhaust pressure was absolutly rediculously high, the exhaust didn't smell at all (makes me think lean), the engine seemed like it would miss or stutter if it was revved quickly (like it would start to revv, stop for about 1 revolution, then resume). Capping the actuator so it would stay closed did nothing at all. I reset the ECU, and the sound of it calmed a lot, and I got some power back, but not much. On the way home, it began to cut out entirely if I went above about 3,250 RPM, the sound started coming back with a mysterious whistle, and the power remained the same. What the hell is going on? Other mods are a full 3" intake, and some negligabe ignition mods. I wondered if the intake is just too wide open so I'm running really lean and between the lean condition and all the air making plenty of backpressure, I'm losing all my power, but I don't think the exhaust is any different from a Prelude Si's other than the manifold, so I shouldn't need a better exhaust, right? And the injectors are different, but it's not by enough, so I doubt both... so what in the hell is going on? BTW, it's throwing codes for fuel inector, knock sensor (which I though F22's didn't have?), and EGR now, and stopped that stupid 22 code.

[ehulst]

I've got a similar problem with mine after the swap( i did this swap friday night been running CEL since then)........mines not idleing at all...sits at just at the bottom line of the tac....throwing a code....[(12345.....12345.....12345.....ex) Code 5?].....smells like shit since its running safe mode.....bogs down fairly good but the power is def there just want this CEL to go away..... ......could also be my TPS sesor....i set that to ear since i wasn't getting a reading from the red wire with my volt meter.....

[SoySauceCb7]

it sounds like you got an intake vacumleak.you should get some either and spray it around the intake manifold. if your idle goes up then you know for sure that you got a leak. check all gaskets. so the intake manifold gasket, the TB gasket, the intake couplers as well as the gasket that joins both parts of the manifold

[jumpman83]

good call, there's a spot around the back of the intake manifold that's supposed to have a vacuum port, but didn't, but it was still open. Looks like I need to figure out what it goes to. The odd thing is, if I close it, the car dies... I'll see if I can figure out the right combo to make it work right...

[ehulst]

hmmmmm......didn't think itd be a gasket.........now it just doesn't idle at all......i mean i have to down shift to a stop and make sure not to let it go below 1500 or i dies....i've tripple checked my vac hoses and they are fine..

[jumpman83]

I got a lot of power back, but it's still not the same as stock, and I have no more power at WOT than I do at 1/4 throttle. Could it just be the injectors can't handle a 3" intake and a huge intake manifold?

[ehulst]

well i just sprayed the mani and its still fine for leaks....the choke is at 750 insted of 1500 or so noramly.......i've tried resetting the ECU but that seems to do nothing at all....its still throwing a MAP sensor code at me and still wont idle properly...


(update)

well i noticed a pear white glow from under my car on the exhaust mani just behind my cat....also the computer its throwing a new code.....which is my TPS sensor( howd i gess)...new thing with idle....its jumping but still will shut off at a certin point...

[ehulst]

[Granite CB7]

^Is the TPS (the one giving you problems) the one that came w/ your H23 IM?
Your F22 one is fine, just cut a slot in each screw head and use your F22 TPS instead, it'll work!

[ehulst]

i kno why the TPS is giving me problem, i can easly adjust it.....thats not the problem its my MAP sensors that are pisseing me off.....all the vac lines are correct....am i suypose to be using a prelude MAP insted of my stock F22? and now it looks at tho my coolant lines are backwards yet again.....hard telling now how screwd my engine is......since its been runing 6 differne't ways since friday....

[Granite CB7]

You can adjust the TPS? I always thought it was calibrated w/ it's T/B from the factory and that's it. I'd like to know how!!! I'm not sure about the MAP sensors and what would affect it. Yeah, the coolant lines look confusing when everythings apart!

[ehulst]

the TPS is adjustable i had to switch mine cause the prelude's was broken....its in the h23 mani how to........the coolant lines have me in a bind i wanna start from stratch on those.... how do they go together?....1 by one from the water houseing.....anythoughts..

[ehulst]

its back fireing outta the manifold now......got my idle some what back but now each time i press on the gas it bogs down alot then backfires outta the manifold then continues onto the tac.....do i need to adjust my timing....still got hte TPS and MAP sensor codes.......sry to keep this thread going..didn't think this would happen with a simple swap...

[ehulst]

ALL FIXED...... ...one of the map sensor ports(#21) was clogged....so i we re cleaned all the ports threw it on still got a werid idle so we think it might be the mani gasket so i'm gonna replace that sometime but no CELs, TPS is set.....everything but the bouncy idle is perfect.....its not as loud as i thoght it would be still kinda buzzy....other wise its a decent performance gain via butt dyno....not too thrilling but its there.......

[jumpman83]

Congrats on yours working. Can somone help me with mine now? I put the stock IM back on 2 days ago. I can't believe the difference in power, it's just sad. The amount of difference between the teo would be great, if the gain of the H23 were the same as its actual loss. I'm still wondering if it's possible that the injectors are just too lean. Could it possibly be any thing else?