White6GAV6
Well-Known Member
Just had this happen to me today, actually. Going to test a few things out and see what I come up with. Hopefully I don't have the spend the $700 or so.
Very rough idle, stalls, on hot starts
- Thread starter beachtech
- Start date
HashGobbler420
Member
This Is how I tested my FPR. this quote is from the hot soak thread.
So i have a question now.
I went back to my mechanic to get my Temp sensors replaced because he swore that was the issue and when i got there he told me I might need my ECU re-flashed. Now ive noticed my fans will kick on at random times for about ten second intervals,even if the engine is hot(they will not stay on).. and my FPR was recently tested on a Pressure gauge and it tested ok even though Storms little diagnoses says its the fpr now like could alot of these little things be malfunctioning because of a management issue? My mechanic insists I need the ecu reflashed, which would be about $100 at the dealership, and that will fix what ever is wrong with the PCM is that correct??
Now, my real question would be, do I need to get the PCM replaced, or will reflashing the ECU fix my issue? I do not know much about ECU yet so if anyone can clarify its very much appriciated.
HashGobbler420
Member
Keep us posted man, im so tired of this issue.
HashGobbler420
Member
Just got off the with phone Honda. apt tomo at 12p dont think reflashing the ECU will fix the PCM. Could my fans not be staying on because the PCM?
This is obviously quite a complex issue, but in the test you did before, you pulled the vaccuum line off the pressure regulator right?? and it started and ran properly. Thus I would suggest just changing the regulator with the same part number - just brand new OEM part.
From what I could find in the manual, the '01, '02 regulators run with a slightly higher pressure, which would require the change to the PCM?? The vacuum line reduces the pressure of fuel to the fuel rail for some unknown reason, but if you take it off and it works, I would just do the regulator swap first. The old one could be stuck or gummed up or just worn out.
The fans likely a seperate issue and should only be controlled by the coolant temp and or the A/C being turned on
From what I could find in the manual, the '01, '02 regulators run with a slightly higher pressure, which would require the change to the PCM?? The vacuum line reduces the pressure of fuel to the fuel rail for some unknown reason, but if you take it off and it works, I would just do the regulator swap first. The old one could be stuck or gummed up or just worn out.
The fans likely a seperate issue and should only be controlled by the coolant temp and or the A/C being turned on
HashGobbler420
Member
Thank you for your reply.
So I did unplug the vacuum line, but I had to plug it not just leave it off.
It did however crank/run a whole lot better. Now, I would typically agree and just replace the damn thing. (Ihave a 2000, so why get 01 02 reg?)(I couldve red that wrong.) BUT, I just had a diag. done on it(a week ago not today at honda) and had the FPR tested and it came back good. But, I just got back from hond dealership (Gainesville fl.) They did a free check on it and their mechanic said all symptoms lead to the IACV being bad it dropped a (temp) code I have the act code somewhere. So my boy said I can just take it off and spray it with carb cleaner and it will be fine. Honda tried to charge me $658 to replace the IACV. But now my question is... could the PCM be causing all the minor things to **** up... like the FPR tested fine but I can fix my bog down with the vacuum fix??? My fans not kicking on IACV error code and? Honda said there was no way to test the actual PCM. I have a feeling they were trying to do what most dealerships do and insist you need to replace parts untill they find the correct one.
Ok, so is the reg somthingIi can to with tools at home, because im not to sure it is the issue but if I can do it myself relitivly easily and cheap ill rule it out just so I can say no I just fing replaced it... lol ughh,, I wonder if I can KGB this...
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CDsDontBurn
Well-Known Member
The IACV and FPR are things you can do yourself. It only takes a few minor tools to do and get done for a quarter of the price it'd cost you to get it done by the stealership. The IACV is right there attached to the throttle body, and the FPR you already know where that's at. Easy fixes.
658 for the IACV replacement is way too much. Can't you just clean it? Take a look at this:
http://www.youtube.com/watch?v=gOECtpdfqyk
BTW I bought that IACV gasket like 4 years ago and never got around to replacing it. If my car does ever act up again I might try cleaning the IACV next.
http://www.youtube.com/watch?v=gOECtpdfqyk
BTW I bought that IACV gasket like 4 years ago and never got around to replacing it. If my car does ever act up again I might try cleaning the IACV next.
CDsDontBurn
Well-Known Member
Definitely. You can pick up an IACV from NAPA or AutoZone for around $120 or so. A little more if you decide to get it from the stealership of course. Changing the IACV itself will probably take about 30min or so.
You can also clean out the IACV as cl206 said. I did that to mine, but it caused a revving issue when in park / neutral. It eventually sorted itself out as the ECU eventually compensated for the cleaned out IACV.
You can also clean out the IACV as cl206 said. I did that to mine, but it caused a revving issue when in park / neutral. It eventually sorted itself out as the ECU eventually compensated for the cleaned out IACV.
Yes, the vacuum line would need plugging as it attaches to the intake air manifold. If left open it would allow extra air into the engine and probably raise the idle speed a bit. Much in the same way that the IACV allows a controlled amount of air to by-pass the main throttle plate at idle.
The IACV code and FPR could be a connected problem if there is an air leak somewhere.
Did the dealer do the FPR test in the hot restart 20 minute failure window?? probably not. This could be a transient issue with that component that will be difficult to find with a standard test. Having the hood up or down could make a temperature difference in the valve that would change how it acts. Tricky.
I did clean out the IACV on our V6 at about 90K miles - just because - and there really wasn't much carbon or crud in it. I don't think that applies to the I4 engines. If I remember correctly, there are a couple of tiny coolant hoses attached to the V6 IACV that have to come off for access, so I would plan cleaning that out when you do a coolant change.
I still think the fans are a seperate issue and not related to any of the other components. They are driven by the A/C being switched on and a coolant temp sensor. I would only worry about those if the temperature gauge is going up.
The IACV code and FPR could be a connected problem if there is an air leak somewhere.
Did the dealer do the FPR test in the hot restart 20 minute failure window?? probably not. This could be a transient issue with that component that will be difficult to find with a standard test. Having the hood up or down could make a temperature difference in the valve that would change how it acts. Tricky.
I did clean out the IACV on our V6 at about 90K miles - just because - and there really wasn't much carbon or crud in it. I don't think that applies to the I4 engines. If I remember correctly, there are a couple of tiny coolant hoses attached to the V6 IACV that have to come off for access, so I would plan cleaning that out when you do a coolant change.
I still think the fans are a seperate issue and not related to any of the other components. They are driven by the A/C being switched on and a coolant temp sensor. I would only worry about those if the temperature gauge is going up.
