ej22 to ej25d swap...not as easy as it looks

Heads, valves, pistons, rods, crankshaft, etc...

Moderators: Helpinators, Moderators

WRXish
First Gear
Posts: 194
Joined: Fri Mar 25, 2016 2:48 pm
Location: Beautiful Downtown Goode, VA
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by WRXish »

It seems that all MAF sensors are not created equal. The one I was running was one I got from a boneyard and I never looked at the brand on it...dont remember what it was now, but the one I put on the car was a JECS I got from Josh, thank you Josh. It runs much better now thank you. I think there is still more to be had, but I am going to drive it for a while and see how it does.
WRXish
First Gear
Posts: 194
Joined: Fri Mar 25, 2016 2:48 pm
Location: Beautiful Downtown Goode, VA
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by WRXish »

So to get the car to a place that most folks would be satisfied with an engine swap took almost a full month working every day resolving things that didnt fit or work and relying heavily on help from this forum. Sadly my local dealer was no help except to faithfully order parts for me and take my money, which is fair enough I suppose, but there is a LOT of specific subaru knowledge on staff there that they refuse to share with a customer who is also an enthusiast. You would think that being a member of the enthusiast group would buy a certain amount help and comraderie. Not there it doesnt. The sad thing is they had an opportunity to help and generate a HUGE amount of loyalty in the process and blew it. Shame on them. What they have done is convinced me to avoid buying anything from them ever again if possible. I wonder if all subaru dealers are like my local one.

But the good news is the car is running pretty well now, still need to do the transmission swap and the lower links on the rear suspension, but other than that it is mechanically in as good a shape now as I know how to make it. The key to getting this engine to run right was the correct ECU, the correct injectors, and the correct MAF sensor. Without those pieces it would never fly. But now it does!!! :) Many thanks to those who helped, Mike Tracy, Josh Colombo, and others. I appreciate it very much.
WRXish
First Gear
Posts: 194
Joined: Fri Mar 25, 2016 2:48 pm
Location: Beautiful Downtown Goode, VA
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by WRXish »

A case here of premature evaluation...still got a slight stumble misfire under load 4th, 5th gear, but it is better. I wonder if the ECU is smart enough to learn what it needs to know to run properly? Or should I look at replacing the O2 sensor now? I had just done that 8 months ago and it was working fine with the old engine. Anyone have any suggestions?
Legacy777
Site Admin
Site Admin
Posts: 27884
Joined: Tue Oct 15, 2002 11:37 am
Location: Houston, Tx
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by Legacy777 »

Tom,

Did you end up going back to the stock air box? If not, I'd also recommend doing that in addition to the things we talked about last night.


Regarding the subie dealership, I'd be a little surprised if they have techs that were knowledgeable in the older subie stuff. They may have that knowledge, but I haven't seen much of it. Some dealers are more friendly when it comes to the enthusiasts, but others are not. It depends a lot on the management of the dealership.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
WRXish
First Gear
Posts: 194
Joined: Fri Mar 25, 2016 2:48 pm
Location: Beautiful Downtown Goode, VA
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by WRXish »

About time for an update. IACV has been reinstalled in the factory configuration, and it was idling weird, throwing cel at random and generally acting like something possessed. Again partly my fault. But things are looking and running much better now. It seems the white and black wires going to the IACV were hooked up backwards. So the IACV was trying to lower the idle speed and it was raising it instead...and throwing codes. So properly wired it runs much better, starts, idles, and so on. There is still some part throttle roughness that I attribute now to not having the IACV adjusted quite right and as far as I know there is no easy way to get that right. IF someone knows a way to do that, please speak up. But it is doing so much better I hesitate to do too much lol. Next step is getting some straight line performance numbers to compare to the old engine. Nothing fancy, just 0-60 using a sane launch method. No 4 grand side stepping the clutch for this one...maybe a 2500 slip the clutch and see what happens.
WRXish
First Gear
Posts: 194
Joined: Fri Mar 25, 2016 2:48 pm
Location: Beautiful Downtown Goode, VA
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by WRXish »

Legacy777 wrote:Tom,

Did you end up going back to the stock air box? If not, I'd also recommend doing that in addition to the things we talked about last night.


Regarding the subie dealership, I'd be a little surprised if they have techs that were knowledgeable in the older subie stuff. They may have that knowledge, but I haven't seen much of it. Some dealers are more friendly when it comes to the enthusiasts, but others are not. It depends a lot on the management of the dealership.
Currently running the cone filter I had on the old engine...may go back to the 45 degree airbox I had but not sure about that yet. You were so right about so much of this mess Josh...major respect for what you know!!!! And the stock airbox may help bottom end torque, but I think the cone filter gets better fuel economy. When I switched it back to the factory box, gas mileage dropped 20%. But once everything is stabilized and where its going to stay for a while I may swap it back and give it another test.

Many thanks for all your help. Any easy way to adjust IACV?
Legacy777
Site Admin
Site Admin
Posts: 27884
Joined: Tue Oct 15, 2002 11:37 am
Location: Houston, Tx
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by Legacy777 »

Tom,

Glad to hear things are looking up! If you have not already done so, I highly recommend resetting the ECU. It will have learned fuel trims with the IAC valve hooked up improperly. Pull the battery cable for a couple hours or you can pull the the EGI/TCU fuse. It's fuse 14 in the driver's side kick panel fuse box.

Did you check the TPS's idle switch?

Regarding the stock airbox it shouldn't have been that large of a difference in mpg. However, if you want to try and make head to head comparisons you need to reset the ECU after every modification so it is starting from the same point. So what I'd recommend doing is resetting the ECU, drive the car and see how things go. Swap the stock airbox back in, reset the ECU, drive the car again, and see how it compares.

What I recommend is a hybrid stock airbox. The stock 90-94 Legacy has a velocity stack in the top piece of the airbox to help smooth the flow of air into the MAF. So if you go with the 45 deg airbox swap that velocity stack over from the stock airbox. The other thing I recommend is remove the snorkel from the fender. It helps remove restriction and you get to hear the intake growl a little more. You can also add a secondary intake pipe to the bottom of the intake box to again remove restriction.

One other thing that could be the cause of your MPG difference is that the cone filters tend to produce turbulent air coming into the MAF sensors. The sensors can't read this correctly so you may actually be getting more air then what the MAF is reading so you're actually running a little lean and getting better gas mileage. But like I said above, try to be as methodical with the changes as you can and do the ECU reset after each modification so you're starting at the same baseline.

Regarding adjusting the IAC valve, the only way to really set it is to see what the duty % is. You can do this with the Subaru select monitor or Vikash's scan tool I sent you a link for. The only other way I can think of is if you have a fancier electrical meter that can read duty % and probe the wires directly coming from the ECU. The only thing I'm not sure about it is since there is a separate open and close wire I'm not sure what those readings will be vs. what the ECU is saying is the duty percent.

Either way, you'd need to see what the IAC valve duty percent is. I've pasted the blurb from my select monitor document. My value when I read it from the ECU was 39.5%.

Mode F12 – By-pass air control solenoid valve (ISC)
25 – 40 % (Non-TURBO) ______________

The other and maybe easier option in the long run is to find another used IAC valve and swap it in.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
WRXish
First Gear
Posts: 194
Joined: Fri Mar 25, 2016 2:48 pm
Location: Beautiful Downtown Goode, VA
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by WRXish »

Its time to kick this thread again...as the sorting process continues. I have a fairly decent running engine now, the IACV seems to be happy where it is and how it is. The engine starts from dead cold revs immediately up to about 2000 then settles over a few seconds to just over 1000 rpm. Once warmed up the idle drops to about 800. Off idle response is good and smooth most of the time. Full throttle is really entertaining and the car is much quicker than it was with the old engine. Couldnt be more pleased about that. But where this package really shines is at highway cruise. Throttle response is really pretty amazing, and climbing hills at speed requires very little extra throttle to maintain speed. In that way it is much less fatiguing to drive on a long trip without cruise engaged. Compared to my 08 leggy with automatic, its worlds better. The 08 takes lots of throttle to hold speed up and down hills at highway speed. And on steep grades it always seems to need at least one downshift if not two. The constant pedaling of the accelerator in the 08 makes it very fatiguing to drive a long ways without cruise engaged.
The one remaining issue with the driveability of the wagon is the moderate load low rpm scenario. It seems that in the 1500 to 2000 rpm range the fueling just isnt quite right and at anything like a moderate load it will stumble and miss erratically. Keep the revs over 2000 and it seems pretty happy. I am still trying to identify for certain that the stumbling only occurs within that rev range...only way to do that is to drive the car. So its getting driven some now on a regular basis. Headed to richmond tomorrow to make engine builder fix the clacking valves and to the transmission guy today to have them recheck their work...drain plug in tranny was loose after they finished their install so they need to verify its all good.
Legacy777
Site Admin
Site Admin
Posts: 27884
Joined: Tue Oct 15, 2002 11:37 am
Location: Houston, Tx
Contact:

Re: ej22 to ej25d swap...not as easy as it looks

Post by Legacy777 »

Tom,

Thanks for the update. Hopefully all the stuff the engine builder & transmission guy needs fix will be made right. Keep us posted on the rpm issue.

Did you end up putting the stock airbox back in or are you still running the pod filter?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
Post Reply