ej25d rebuild

I have no idea where I went wrong, but after rebuilding my ej25d and installing it it's running like crap. Did the ej25d wiring harness have any plugs that didn't connect? I had a plug that i couldn't find where it went, it's a round grey plug next to where the big plugs are on the top of the engine near where it mates with the transmission.

Pics help.

there's going to be a speed sensor plug, NSS plug and an O2 sensor plug... its one of those three, whats wring with your car?

i had to rebuild it because the head gaskets were out and turned out most of the bearings were bad too. after rebuilding it and dropping it in, the engine ran terribly, it shook a lot and sounded like it was missing a cylinder. someone suggested that the timing could be 180 out from the crank, since i did forget to check for tdc when i did the timing. so i flipped the crank 180 and now it's worse, the engine doesn't shake at all but it sounds like it's missing 2 cylinders now.

what's the difference in the shim size between the intake and exhaust?

I checked and it was an o2 sensor that was unplugged. only problem is, although it helped, it's still running like crap. it sounds like it's missing a cylinder at idle but when i push on the throttle it evens out a little.

You don't need to check for tc when doing timing, just make sure the cam and crank marks line up correctly. I wonder if your timing is off. Have you checked all of your spark plug boots to make sure they are connected all the way as well as if all the injectors are connected?

yea. i've redone the timing several times, adjusting it a tooth either way. it actually runs the worst when it's perfectly in time. i've got all the plugs, wires, and injectors plugged in.

the only thing i can think of that could've gotten mixed up would be the valve shims. when i had taken the heads apart the valve shims got mixed together and may or may not have gotten put back in the proper slot.

someone suggested that the timing could be 180 out from the crank, since i did forget to check for tdc when i did the timing. so i flipped the crank 180 and now it's worse, the engine doesn't shake at all but it sounds like it's missing 2 cylinders now.

 

Okay, this is the statement where I find issues. Flipping the crankshaft 180 degrees on the timing shouldn't do anything you just said. If the car is running, and you flip the crank, it will just crank and crank and crank and never start. This is because there is zero compression.

 

So...

 

Double check your timing after you place the crank gear on the crankshaft correctly.

There's only one way for the crank gear to go onto the crankshaft. i stuck a wire hanger into the #1 cylinder to check for piston placement and it felt like it was in the same spot whether i had the crank 180 out or not.

Hmm, yeah, there's a keyway....

 

But, I do know from personal experience, that everything I just said about spinning the crank, is 100% correct.

it ran 180 out, didn't smack any valves. even when i adjusted the cams 3 teeth out it didn't smack the valves. in all the timing situations i've done on it it runs every time, just only on 3 cylinders.

can the valve shims being in the wrong place actually kill a whole cylinder?

I would thing that the valve shims only fit the one way....

 

Which cylinder(s) is not running in what configuration? I really am starting to think your timing is way off. Take some pictures of how you have the timing set up.

did you use the correct timing marks for the crank and cam sprockets.?

 

trying to run the engine with the crank ''180 degrees out'' sounds scary.

if you do not have the cam and crank sprockets lined up on the correct marks, you can and will bend valves.

and if the crank is 90* off (the arrow instead of the hash mark on the rear) i don't think it will run at all.

and it WILL bend valves.

 

valve shims can get mixed up, especially if they spill out onto the floor when removing the cam shafts and / or the heads.

the only check is to do a compression test.

 

are all the vac line connected.

a vac leak will cause it to run crappy.

 

make sure the plug wires are fully inserted into / onto the coil.

the boots can slip down and limit how far the wires will insert.

 

it sounds like you have the timing off, idles like crap, but smooths out at speed.

i had a valve job done, and i think that they have to grind down part of the top of the valve stem to compensate for the weight taken off the valve face, but i never had the heads re-shimmed.

 

does that sound right?

i think it's cylinder 2 that's not firing. i've got the timing lined up exactly as it's depicted in the manual.

it sounds like you have the timing off, idles like crap, but smooths out at speed.

 

A vacuum leak will also cause this issue. All vacuum lines need to be checked as does your IACV (idle air control valve).

i've gone through everything and the only thing i found unplugged was the 02 sensor, which i plugged in.

i've gone through everything and the only thing i found unplugged was the 02 sensor, which i plugged in.

 

Spark plugs? Fuel filter? Spark plug wires & ignition coil? Just covering the basics.

Is cylinder number 2 not firing at all? Or intermittently? Is there spark? It the injector working? Have you done a compression test?

all those things are plugged in, i know it's getting spark. i haven't been able to do a compression test yet because at 90 psi the purge valve blew out and i haven't been able to find it. i've got a buddy that's supposed to be bringing over a compression tester so hopefully i can have some numbers up later.

I still feel like timing was messed up at some point and you bent some valves. We'll be a step closer once you get the compression numbers in.