Hey all,

So I've had my 99 GSR for a few months now and it's been a lot of fun! Unfortunately the previous owners have abused the poor thing so much that a CEL isn't too uncommon. Well I finally had a period of sweet sweet non-CEL heaven. But with all project cars, it wasn't too long before the codes came back on. This time in full force!

Here's the situation, I have 4 codes and I'm not sure if they are related or not. Here they are:
P1259: VTEC System Malfunction
P1359: CKP/TDC/CYP Sensor Circuit Malfunction
P0505: Idle Speed Control System
P1457: EVAP System Leak Detected (Canister Area) <---- This code appeared twice for some reason when I took the car to autozone.

Now don't get me wrong, I did A LOT of research before deciding to post here, but so far I've come up flat on answers. Interestingly enough, people who are experiencing the P0505 code are having a different problem than I am. When they start their car, their car will idle shoot up to 2000-2500 RPMs. Mine is the exact opposite. I will start the car, and then be forced to push in the gas pedal due to fear of stalling out instantly. My car idles really low before it "warms up". This has led me to believe that it may not be something wrong with my IACV but instead may be caused by one of the other codes.

The P1259 code has been a living nightmare and keeps popping up from time to time. If someone knows any answers to this please dear god tell me.

Haven't done too much research on the P1359 and P1457 code and am completely lost.

If anyone has any answers please help. Any feedback is greatly appreciated.

 

anybody...?

 

https://www.justanswer.com/honda/0y3...-4-engine.html

https://www.ericthecarguy.com/29-obd...function-honda

P1359 Engine Trouble Code - P1359 OBD-II Diagnostic Powertrain (P) Trouble Code Engine OBD Code | EngineTroubleCode.com

https://honda-tech.com/how-tos/a/hon...e-p1457-375881

 

Whelp I got the dreaded P0505 yesterday. My Idle had been doing weird things lately, it seems like it has slowly been going higher and higher and may be effecting my air conditioning as well. Then yesterday out of nowhere, it started doing a really hard 1000-2000 surge. It always seems like as soon as you fix one thing, another totally unrelated problem pops up. So first thing I checked out was my TPS and MAP sensors were reading correct (they showed normal readings on my OBD2 reader). Next, I have to test out the IACV (idle air control valve) and check for vacuum leaks. I really hope I don't need to buy a new IACV ($290 from Honda). I will probably just buy new throttle body, MAP sensor and IACV gaskets, take every thing apart, clean (maybe soak the IACV in diesel overnight) and reinstall everything with new gaskets and hope for the best. I did most of this 2 years ago, I guess its time to do it again -_- . Hopefully my intake manifold to cylinder head gasket isn't leaking, but hey, maybe then I'll "have to" get one of those sweet Hondata gaskets and clean up the head lol...

 

p0505. Replace iac with known good part. It is a wax valve that works just like a thermostat. Hard to diagnose. Easy to replace. You can take it off when its cold, and see what it looks like in there. Sometimes they rattle.

P1359 replace dizzy with known good part. You can also ohm out the sensors. #1 falure for dizzy, coil, and sensors is secondary ignition falure. I.E plugs/wires.

Vtec code 1259. Check vtec solenoid with 12v. See if it makes an audible click. Ohm sensor. Dont know the value uff the top of my head. Check screen in gasket for vtec solenoid. The get plugged from infrequent oil changes.

Evap code. Check evap solenoids, and get back to me.

This is all off the top of my head from experience. I might be wrong about something, but ooh well. Doctors can be wrong too.

 

Isn't the "wax valve", actually the Fast Idle Thermo Valve (FITV) underneath the throttle body with the coolant lines going in and out?
I believe you meant to say the Idle Air Control Valve (IACV), that is on the back of the intake manifold and controlled by the ECU, not coolant temperature/wax.
Both can be removed, inspected/cleaned and then reinstalled with new gaskets, to see if that fixes the issue, before buying a new, costly Honda part...

 

huh? Sorry, I was only aware of the one with the coolant lines. Those misbehave sometimes. Might have to research that code a little more.

 

Well I think that they both have coolant lines, but the FITV is strictly coolant temp controlled, mechanically with wax expansion, while the IACV is controlled mainly by the ECU.

 

the wax one. Google it. It will tell you how to test it
I would go after that

 

So my Integra's Idle had been getting progressively worse and worse over the last couple of weeks. It had been getting higher and higher and starting to bounce at 1500 after warming up. Also the AC would not work while in neutral or park. So I figured I would give the IACV another clean (it had been 2 or 3 years). On Friday afternoon I cleaned it out with throttle body cleaner. I sprayed it in, soaked it, let it soak for 5 10 minutes, shook it, dumped it, repeated for maybe an hour or two. It really didn't look dirty at all and nothing really came out.

On Saturday I was debating tossing it back in or picking up some simple green and giving that a go. I did and boy am I happy that I did. After the first soak shake and dump, a whole lot of dirt poured out. The carb/throttle body cleaner spray did literally nothing. So I decided to repeat that several times, each time dirt came out (keep in mind, the IACV really didn't look dirty when I pulled it out). Then I let it soak in the simple green all of Saturday night and then rinsed, shook, dumped, repeated until soap bubbles stopped coming out on Sunday morning. Finally I put it upside-down in the oven and baked at 250F for an hour to dry it out before installing it.

I can finally say that the car, at 200k miles, is running like brand new (I have recently done a ton of other maintenance as well too). It is finally starting fast, idling perfect, no idle bounce, the idle speed does not change at all when going neutral to drive or the AC clutch and fans clicking on, always sits at about 800 rpms and finally the AC is working perfectly as well.