Nytro97

Hi, I have codes p1078 and p0325 on my 2002 CRV with 90,000 miles. I know the p0325 is the knock sensor and the p1078 is the intake manifold runner control system malfunction high RPM.
Just wondering if anyone has had these two codes at the same time, The car seems to run as normal....just the check engine light is on. I'm hoping maybe the intake and runner valves just need to be cleaned. (wishful thinking)
Any experiences guys.
Thanks, Tom

tech8

UK-Kev

Hello, have a look at the attached.

Nytro97

I did some checking....I have vacuum where it needs to be and the rummer control valve holds vacuum. I am going to remove the intake manifold and clean it and the runners. Maybe it is just gummed up.
Thanks, for the replies

Tom

Miguel A

How's it going? Did you find your problem. My 2004 Crv just popped the same codes as you.

Nytro97

I haven't got around, or had the mood strike me yet to do it. To many things have come up lately also. I will reply when I do it.

Tom

Miguel A

Thanks for response. I was wondering with proximity if squirrels got to harness. Project for tomorrow.

Nytro97

Well I have taken it all apart and it does not look like it was gummed up. The plastic bushing and o ring that is suppose to be at the end of the rotary valve assembly is stuck in the bottom of the manifold.(I don't think that is suppose to happen.) I need to get the rubber boot between the throttle body and air filter box. I must have tore it. I will get the bushing and o-ring out of the manifold and see how it fits on the end if the valve. I may just cry and buy a rotary valve assembly.and maybe the knock sensor...because it is cheap and easy to get to right now.

The engine does create vacuum at the diaphragm and the diaphragm doe hold vacuum with no leak down.. How have you made out Miguel.................................

Nytro97

Well I got back to it...........I replaced the rotary valve vacuum solenoid (in case it was sticking) and the knock sensor (because it was right there) and put everything back together. Now it is galloping between 1200 and 2000 RPM's ....I'm starting to have fun. Will get my brothers scanning tool when he get home and see what thins show.

Nytro97

Just wanted to follow up to help some one else.....
This all started with just the P1078 code.The IMRC. (malfunction high RPM) With just an engine light on and 2002 CRV ran perfectly.

Now the idle surges back and forth between 500 to 1300 RPM's

I reassembled and replaced the IMR solenoid. I was not getting the P1078 code anymore but now getting the P0505, P1077 and P1505.
Not feeling right about the stuck bushing in the bottom of the manifold, from the end of the runners. I found a complete new sealed in box Honda manifold with rotary valve for $200.00 and installed it. (just ruling out any possible issues.)

I have checked all the vacuum hoses and don't see any problems. With the intake boot off I block the IAC port in the throttle body with my thumb and it idles perfectly. Also when I cover the throttle body the engine will stall.


Well I took it apart again ...double checked all hoses and replaced the PVC valve just in case. I removed the idle air control valve from the throttle body and cleaned it with carb cleaner.

Reassembled and started it up , engine was running a little rough but smoothed out and idled good. Added a little anti freeze, finished installing the rest of the plastic top and bottom on the nose etc.

Started the car again to check and it is surging again....I have had enough. I must be a bad idle control valve.


I repaired a leaking brake line...Could get to them by removing the air cleaner box and Installed a new Idle air control valve .Now The idle is perfect. Cleared the codes and hope the engine light stays off.

Nytro97

Light came back on and the code is P1077......

Nytro97

Well for information sake to help someone else............ I still had the light.
Took it to a local repair shop, they put it on a scanner. The NEW Vacuum solenoid that I put on is defective it was sticking.....He told me to take the car home and put the old one back on and let him know if the light goes out.

The light has gone out. It is an awful thing the poor quality of parts these days. All this caused alot of extra stress, money and work

Long story short it was the intake runner valve, even though it held vacuum.

Miguel A

I hadn't had a chance to mess with my car. Light would go on then off for no reason. I read your comments did you replace the IMRC valve with a new one or was it something else?

Nytro97

It was the IMRC valve in the end.
Even though it held a vacuum and seemed to work and rotate when vacuum was applied. Like I had said I bought the vacuum control solenoid (not OEM) thinking my IMRC was OK. But when the light did not go out I replaced it.
(found a new in box OEM still sealed manifold and IMRC complete on Ebay for $200.00 7100-PPA-A01 hell of a deal ). Light still did not go out and completely baffled, I took it to a garage and he said the new solenoid I put on was sticking. Told me to put the old one back on and see what happens. The light now is off and has been for the last few weeks.

Miguel A

Ok now makes sense. I misunderstood. I took out the valve. Lots of oil in there. Replaced PCV valve and cleaned out valve. Also a full tuneup. I bought car recently needed lots done. If comes back I'll replace the valve. Not a cheap part.