after swap, new engine can't idle

gustavohuber · Post by **gustavohuber** » Thu Sep 15, 2005 8:23 pm

I'm hoping this is going to be some little thing I missed.. after swapping in a longblock that Matt Monson sent me for my knocking '93, I can't get the new guy to idle reliably. It cranks and cranks, but won't take, and if it does, it runs super super rich, and flails wildly between almost stalling and about 1500 rpm. if I give it gas, it jumps straight from about 2000 to 3000-3500 , and as soon as I back off the gas all the way, rather than dropping to an idle, it stalls out. I redid the timing twice, and am POSITIVE its dead-on, also it has new ngk v-power plugs (correctly gapped), magnecor wires, a diamond pack, and a clean k&n filter. I checked the intake for rags or other oversights.. but get this.. after redoing the timing on tuesday, I fired it up with no accessory belts, and it started right up, and still did the shoot from 2-3500 rpm, but dropped back to a stutter, and then up to an idle. I've checked all the electrical, as well as the whole fuel system (pulled the pump, checked all the connections, cleaned the little bag thing, bought a walbro, but it doesn't seem necessary, so I may return it. Any ideas would be really welcome. Also, any ideas of what to do with a pulled EJ22 with a nasty-sounding rattle (everyone agrees it sounds like a rod knock) and good heads are more than welcome. Thanks.

Post by **Legacy777** » Thu Sep 15, 2005 8:46 pm

Can you provide some more information on what exactly what swapped out/in, etc. Year, model, at/mt engine, etc.

gustavohuber · Post by **gustavohuber** » Thu Sep 15, 2005 10:15 pm

Well, I hesitate to answer this because of the reactions it might get, and the way I imagine it could inspire a lot of people to call this a bad idea and lost cause.. but I stand by Matt in thinking that this really should work...

what came out was the stock EJ22 n/a from a 93 5mt legacy AWD wagon (USA federal, if that matters), what went in was a 98 EJ25 short block with 93 EJ22 n/a heads and the thicker of the two possible EJ25 headgaskets.

Matt has built that hybrid before, and swears by it. The cr is higher, but not massively so..

Busdriver · Post by **Busdriver** » Thu Sep 15, 2005 10:18 pm

YEAH, for the AWD 5MT Wagons!!

gustavohuber · Post by **gustavohuber** » Thu Sep 15, 2005 10:25 pm

absolutely, there arn't words for how i love this wagon, squeaky and loud though it is. It gets AROUND! I was just hoping that having a 2.5 with a high CR under the hood would turn it into even more of a mean little asskicker, but unless I can get it idling, I guess I'll have to part it out or rent a parking spot and have it towed there.

Post by **Legacy777** » Thu Sep 15, 2005 10:50 pm

So you are using all of the 93 stock ej22 n/a sensors and such?

All you changed was mechanical stuff.....I don't see how that should greatly affect things, even with the slightly larger displacement.

I'm assuming the battery was out during the swap, so the ECU should be reset. Anything else you can think of?

skid542 · Post by **skid542** » Thu Sep 15, 2005 11:00 pm

Are there any codes? Have you checked all the sensors to make sure they are operating right, temp, maf, etc.?

Matt Monson · Post by **Matt Monson** » Fri Sep 16, 2005 12:26 am

Hey Gus,
I thought those heads had my name on them?

Anyways, I have suggested every single thing I can imagine that would make this car not run right. I just don't get it. I have seen this engine in both Legacies and Imprezas without this issue.

We did have an idle issue with Diz's Impreza, but it came and went. It was really weird. The car would run fine for weeks on end, and then one day you would clutch in, get off gas, to downshift after a turn, and it would die mid turn. Then you fire the car back up, and it runs like nothing ever was out of place...

gustavohuber · Post by **gustavohuber** » Fri Sep 16, 2005 1:27 am

All the same sensors, no codes, no CEL lately, though before I redid the timing on tuesday I thought it was throwing a light.. ECu has been reset a bunch of times. I havn't manually checked the voltages across the different sensors, but it would throw a code at me if they were failing, right? it seems like if I could just force it to idle higher, then it would work fine, but as it is, it wants to idle so low that the load of the accessories kills it. I just don't get it. One thing that just occurred to me today is that maybe something crawled in the airbox while I had car in the warehouse with no engine in.. and now its blocking the airway at low pressures. The other thing it might be is a vacuum leak, but I have really no idea where the vacuum lines are or how to find a leak anyway.

Matt, the heads are yours if you still want them, I just figured since you hadn't mentioned them you didn't want them anymore. Before I send them out though, I need to get this thing running, and know that I'm not going to have to rebuild the sad old 2.2 and put it back in. Are you in dire need of them? Sounds like you're up to your eyes in projects all ready.

Also, what do you guys think about underdriving the accessories if its not just something in the airbox?

Manarius · Post by **Manarius** » Fri Sep 16, 2005 1:56 am

This may be stupid, but did you adjust the screw on the throttle? Maybe I'm wrong...

skid542 · Post by **skid542** » Fri Sep 16, 2005 2:19 am

hmm.... it should throw a code if something is wrong but that doesn't mean it will, I'd double check them just to be sure. Checking the air tract is a good idea to, eliminate the possiblities one by one. As far as the vacuum hoses go, I'd just start replacing any hoses that look a little old. I think there was a vacuum tube diagram that went across the boards a few weeks ago?

I wouldn't give up just yet, I think you have a good motor, just need to work out the quirks.

vrg3 · Post by **vrg3** » Fri Sep 16, 2005 3:30 am

This also may be a dumb question, but is the entire intake tract correctly plumbed up? This sounds like what might happen if, say, the IAC valve hose was disconnected.

gustavohuber · Post by **gustavohuber** » Fri Sep 16, 2005 8:48 am

I'll get on checking those hoses.. here's something else I noticed- the cam sensor's wire is pretty hard to wiggle.. looks like maybe I smooshed it under the mount for the AC compressor. That would cause all kinds of awful timing problems, right? but it would also throw a code... thanks for the hints. If anyone wants to verbally diagram what my intake plumbing should look like, please do. I checked the filter, its clear and clean, as are the hoses... thanks again, everyone.

skid542 · Post by **skid542** » Fri Sep 16, 2005 3:17 pm

Yeah you would think that if the cable were squished and shorted you'd get a code. Not really sure what to tell you about it though

, however, I took a lot of detail pictures of my old EJ22E before I started my swap, for reference sake. There are a lot of pictures of the air intake plumbing and all - www.thawa.net/gallery/EJ22ESwap . Hope that helps a little.

legacy92ej22t · Post by **legacy92ej22t** » Fri Sep 16, 2005 3:32 pm

Sounds like an IAC problem to me. You also might want to check the TPS.

Do the EJ22 and EJ25 use the same IAC? Which one did you use?

Post by **Legacy777** » Fri Sep 16, 2005 6:20 pm

The cam sensor wire should be routed around the outside of the intake manifold.

Verify the sensors, they will not always throw a code.

You can spray starter fluid around the vacuum lines. If the idle goes up, you have a vacuum leak.

Check the TPS that the idle switch is set properly.

gustavohuber · Post by **gustavohuber** » Fri Sep 16, 2005 7:18 pm

I've never messed with the idle screw, but i'll check the iac and cam sensor when I get back to work..

Matt Monson · Post by **Matt Monson** » Fri Sep 16, 2005 7:28 pm

legacy92ej22t wrote:Sounds like an IAC problem to me. You also might want to check the TPS.

Do the EJ22 and EJ25 use the same IAC? Which one did you use?

His engine is all Ej22 except for the shortblock. The only thing that was changed from a stock set up was the block itself. All sensors, wiring and vacuum lines should be stock EJ22 Legacy...

But IIRC, there have been a handful of guys here with IAC problems that were not throwing codes...

gustavohuber · Post by **gustavohuber** » Fri Sep 16, 2005 7:37 pm

also, during the swap, the manifold basically came off as one chunk with injectors, rails, sensors and the works still attached, so none of that has been changed in the least. Is there any way to manually test the IAC or the cam sensor with a multimeter?

Matt Monson · Post by **Matt Monson** » Fri Sep 16, 2005 8:35 pm

Oh,
and Gus. There is no hurry on the heads. Hang onto them as long as you need to...

Post by **Legacy777** » Sat Sep 17, 2005 3:54 pm

http://www.main.experiencetherave.com:8 ... C_Diag.zip

gustavohuber · Post by **gustavohuber** » Wed Sep 28, 2005 7:03 pm

So, I've checked the IAC, the cam sensor, and the ECU, and everything read the right voltage/impedance-- but two lines on the ECU which should have been 7v were 12v.. any ideas? seems like it should be working. Anyone have a spare IAC or ECU I could buy?

def09 · Post by **def09** » Sat Oct 15, 2005 8:45 pm

Does the crank sprocket matter? The teeth and spacing on the sprocket from the EJ25 and the EJ22 the same?

gustavohuber · Post by **gustavohuber** » Sat Oct 15, 2005 8:49 pm

from what I understand, the engines are identical except for different stroke. The sprocket is from Matt as well, and he's done this swap before. I'm totally stumped. crap.

wiscon_mark · Post by **wiscon_mark** » Mon Oct 17, 2005 1:21 am

vrg3 wrote:This also may be a dumb question, but is the entire intake tract correctly plumbed up? This sounds like what might happen if, say, the IAC valve hose was disconnected.

+1, sounds like you're running lean.

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after swap, new engine can't idle

after swap, new engine can't idle