I have tried three different EGR valves, a block off plate on and a new solenoid. The problem has got better each time, but after driving it for two hours the 12 engine code now comes on instead of after 15 minutes like before and the prelude begins idle bouncing between 1 RPM and 1.4 RPM as usual after the EGR light comes on. Then, I turn the ignition off and back on and the engine code and idle bounce are gone.

What are the possible fixes?

Thanks

 

When i got the EGR code I hade to clean out the EGR valve and all the ports on the intake manifold. car runs fine now. hope that helps.

 

For additional information, my prelude is a 92 prelude S with a jdm f22b swap.

 

Also, ecu is p39

 

Well does cleaning the ports really matter if the system is using a block-off plate?

cheers,
Beepboy

 

Its back to its normal behavior now, EGR light and idle bounce come on after 30 min - 1 hr.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepboy &raquo;</TD></TR><TR><TD CLASS="quote">Well does cleaning the ports really matter if the system is using a block-off plate?

cheers,
Beepboy</TD></TR></TABLE>

no that shouldn't matter then

I also think that the ports in the IM need to be cleaned.

 

when i did my jdm f22 the idle did the same thing its the computer getting use to the new motor will go away in a couple hundred miles

 

Ok, EGR is back on with no block off plate. The idle is running very rough, it is putt putt putting, compared to how it was smooth with the block off plate on. Its idling at 750. The "12" light came on again after over an hour of driving. I haven't driven 200 miles yet to get the ECU readjusted as one guy suggested, but I plan on giving that a shot. I may need to clean the Intake Manifold, I sprayed it through the throttle body opening, not sure if this will do the job or not? Let me know, I'm still experiencing the "12" CEL after an hour or so of driving and now a rough idle with EGR on.

 

if you have a rough idle with the egr on there, the valve is most likely stuck open some and leaning it out at idle

the idle bounce coming about when the CEL goes on is odd, but you should try to clean out the throttle body and the IACV. maybe try a bottle of seafoam if you trust it.

no spraying cleaner into the throttle body will not clean out the egr ports.

 

I haven't cleaned the intake manifold yet, but I plan on having that done. There isn't much adjustability with the idle adjust screw. The CEL "12" is now coming on within a mile or two instead of 30 - 60 minutes that it took before. Also, it is starting to idle bounce early on as well even when the CEL isn't on. The car is running fine otherwise, I don't think there's anything wrong with the distributor since its picking up nicely off gears.

 

Ok, I had the car checked by an expert and:

EGR Valve Code - Insufficient Flow
Air Passage Clogged - In Intake Manifold Assembly
Will Need to replace Manifold Assembly

The dealer could not order parts for the F22B japanese engine.

I'm now on the lookout for an intake manifold that will be turbo ready when I decide to switch to turbo. Check the topic below that I started for the intake manifold:

https://honda-tech.com/zeropost?cmd=fshow&id=4

 

You can clean out the egr ports on any honda im i think. On some of them you have to unbolt a plate and others you have to pull plugs out. I think you are the latter. It isn't the easiest thing but it isn't the hardest either. I have seen a writeup somewhere on here I would search for it. Also I think the f22b uses the same bolt patterns as the h23. You could search for that too.

 

can you have the egr bolted in the manifold but it not working? i have a p28 but im not sure if egr is used or not. what happens if i unplug it but it is being used, will it be a big deal?

 

Here is an update on my situation with the 1 to 1.4 RPM idle bounce:

After putting in another throttle body, we have narrowed it down to IACV (which was replaced before) and ECU, which is showing P39 J-AT (automatic computer). The car is a manual transmission and needs a P39 MT.

We're going to put a P12 ECU in to rule out the IACV as the cause of the idle bounce.

It would be helpful if someone has a p39-n01 lying around for sale or if anyone knows where to get one?

Thanks!

 

Dude, your Intake manifold is okay, it doesnt need to be replaced. All you have to do is clean those egr ports out and put it back on.

1. Take manifold off
2. Drill through the EGR Ports
3. Clean whole intake real good with carb cleaner, while its off the enginge
4. J+B weld those ports close again
5. Reasemble IM and say a prayer you did it right.

Its simple but can be a pain in the *** cause some off the bolts on the IM are hard to reach.

I think there is more info in the FAQs

 

Thanks for the reply. A new intake (H23) was put on and the old one was actually clean, so the intake wasn't clogged and not the problem.

The part that has been causing the idle bounce appears to be the ECU. The ECU in the car was P39-AT and we tested a P12-MT in it today and the idle bounce is gone and the car is running smoother than ever, but loss of power because we need a P39-N01 (MT) for the JDM F22B engine in the car.

Code 12 is still coming up "EGR" even with the new ECU in it. The EGR is receiving power, we believe it might be the wht/blk data wire bad or more likely the EGR valve may need replaced. We have tried two other EGR's in the past with the same code coming up, so three EGRs total tested and sprayed out first. The EGR is blocked off with a plate between the EGR valve and manifold. I can't rule out the EGR vacuum control valve or EGR control solenoid valve.

Any help on this EGR problem would be greatly appreciated or any help in finding a P39-N01 (MT) JDM ECU.

Thanks!

 

I'm having the same exact with my H22 swap. I've replaced three EGRs already, and it's still throwing the code.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by oneprelude &raquo;</TD></TR><TR><TD CLASS="quote">I'm having the same exact with my H22 swap. I've replaced three EGRs already, and it's still throwing the code.</TD></TR></TABLE>

I am/was in the same boat. What you can do is re-run your wires from the Ecu to the Egr valve. That should help.

I just completly deleted the thing. I will be ordering a new ecu in the soon to come months. One that doesnt use an EGR. It cleaned up the engine bay.

Although there are some warnings to doing that.
For one, the EGr recycles exhaust into the IM lowring emmissions.
2. It warms the car up quicker.

I have taken to turning the A/C on in the dead of winter while starting the car. Warms up twice as fast.

 

Thanks for the input.

We opened up the P39-AT ECU and turned it into an MT (manual transmission computer).

We switched around a jumper according to these instructions: http://mycomputerninja.com/~jo....html

Here are some pictures of the work we did on the P39-AT to make it a P39-MT:

http://homepage.mac.com/beepbo...1.jpg

http://homepage.mac.com/beepbo...2.jpg

http://homepage.mac.com/beepbo...3.jpg

http://homepage.mac.com/beepbo...4.jpg

I'll refocus on the EGR problem after the P39 is reinstalled. Our plan is to do a continuity test on the black/white wire coming out of the EGR to the ECU. I can't take the EGR out completely and delete it.

 

The AT to MT ECU conversion explained above has worked! We installed the P39 ECU AT to MT conversion and the idle bounce has disappeared!!!

MAKE SURE YOU DON'T RUN AN "AT" ECU ON AN "MT" CAR. THIS HAS CAUSED OUR IDLE BOUNCE PROBLEMS.

Running a P39 "AT" modded by the process listed in the post above is better than buying a custom board since the P39 ECU is optimized for the F22B engine.

 

My experiences with EGR (12)... EGR will come one usually when the car has a load on it like going up a hill... You can pull car over turn it off and then on and it will be gone untill next hill ... but yes idle will fluctuate around 2500 RPM. This is normal for the EGR symptom. Acts like a small miss. I have everything routed right and vacuum lines hooked up right in the H22 DC with P13. Only thing else it can be is the EGR it self and I just need to clean it out (carbon build up). Doesn't hurt the performance as it may sound with your issue.