January 28, 201412 yr So I have been playing with engines on my 96 Legacy L for quite some time. Some of you know, some of you don't. I have been having weird issue that I cannot seem to figure out. To start off. I had a 12:1 compression EJ25D/22E combo with delta cams. This motor ran like a top for 8k miles. Yes 8k. Motor was un-tuned on 92 octane. It was an experiment. Ran great till the day I blew a hole in the #4 piston. I then built a standard frankenmotor. You know the one with stock EJ25D pistons and cammed Ej22E heads. Stock head gasket size on both of these motors. This motor ran great until about 15k miles. Then it started to burn oil and all that jazz. Also started to idle really rough. I had scored the cylinder walls on the last motor when installing the pistons so I figured that would eventually happen. Decided it was time to build another short block. So I built an EJ251 with ACL race bearings and NPR piston rings. Cylinder walls are great on this motor. Short block is solid. Got this motor put together and used an STi HG when doing this motor. Same heads as I started with. I still have the same rough idle. Sporadic idle sometimes but not all the time. However always rough when warmed up. If the car has been sitting over night and I go to start it in the morning. It starts like it normally would but slowly revs up to 1.5k RPM's (cold start idle) but while it is doing this it is misfiring. Every morning this happens. About 30-45 seconds later this stops and the motor clears up. Wondering if my issue is in the heads. Since that is all I used from the last motor. So far what I have done. Crankshaft Postion Sensor Camshaft Postion Sensor Checked timing Replaced coil pack NGK plug wires New plugs Coolant temperature sensor Smoked tested the intake. No vacuum leaks. Replaced the MAF with a known good working one Replaced the IACV with a known good working one. Replaced the ECU Oxygen Sensors Cleaned the fuel injectors Replaced fuel filterFuel injector o-rings Probably a few other things. Next step I am going to do a Leak Down Test. Just here looking for more ideas because I am just about out of them. Edited January 28, 201412 yr by 96LegacyEJ22
January 28, 201412 yr What cams and compression ratio are you running now? How is the knock sensor and EGR valve/controls. Get yourself a vacuum gauge (poor unloved tool that is a really handy and should be a must for stuff like this) and tell us what it does. Edited January 28, 201412 yr by nipper
January 28, 201412 yr Author Knock sensor is good. EGR is removed. Also has a non EGR ecu. Delta mild cams. Ej22E heads. 11.5:1 compression based on what I am reading. For the Ej251 with the sti HG's
January 28, 201412 yr I would try to get an idea of just how much compression you have and run a leak down test to see what/where it might be leaking. Also agree with the vacuum guage, very useful if you know how to interpret what it's telling you. You're using 22E heads right? Solid lash adjusters or hydraulic? Have you checked lash clearance?
January 28, 201412 yr Hydraulic lifters are nice for keeping away noise, but collapsed lifters making noise is not the only problem they can have. They can also clog and pump up TOO MUCH and hold the valve open. Clicking lifters almost never cause misfire or rough running problems. But one that holds the valve partially open will cause a misfire for no obvious reason.
January 29, 201412 yr Vacuum gauge, http://www.classictruckshop.com/clubs/earlyburbs/projects/vac/uum.htm
January 30, 201412 yr Author Video never seems to come out good. Anyways. Motor stalls hard when coming down from revs and sometimes just shuts off randomly. I checked my timing and it is half a tooth off on the drivers side. But if I were to adjust it at all it would be just as far off on the opposite side. Did a leak down test and all are between 15-17%. So they are all consistent. When all the timing marks are lined up is it normal for the intake valves to be open on cylinder 2 and the exhaust open on cylinder 4? Got one step colder plugs and gapped them to .28 with no change.
January 30, 201412 yr Yes, valves on 2 and 4 are open when the cam sprocket is at proper timing mark. Which way is the timing off? Clockwise or counter? It should be clockwise because that advances the cam slightly, and as the belt stretches with age it will gradually come into proper time rather than go further out.
January 30, 201412 yr Author It is slightly retarded on the driver side. The tooth count is correct from side to side however. I am using a pretty thin head gasket. So thought that would cause that but not sure.
January 30, 201412 yr the 2.2 I built with delta cams did not run good weak and rough running something with the cams Put ej2.5d twin cam heads on same motor and it roared. Something dident work right engine was very sluggish and no bottom end power
January 30, 201412 yr Head gasket thickness wont make that much of a differnce as the tensioner can make up for it. one tooth off can account for a lot of problems.
January 30, 201412 yr Author Never had an issue with power. Just idle. I know obd1 runs rough with cams. My buddies have the same setup I do with no issues
February 1, 201412 yr Author So I did the vacuum test. The first video is of it being semi cold (coolant gauge on the C mark). Second video is after it is warmed up @ ~750rpm idle.
February 4, 201412 yr Hrmm, that gauge is steady but a little low. Can you do the gauge again while goosing the engine? What is your elevation ( to know for correcting the vac gauge reading )? Have you retimed the engine? The bouncing needle can point to the timing being slightly off or worn valve guides (but usually a little more needle movement) http://www.motor.com/article.asp?article_ID=457 Edited February 4, 201412 yr by nipper
February 4, 201412 yr I could hear a rather loud vacuum leak in the bottom video. Any idea what's leaking?
February 5, 201412 yr Author In the second video it's between 14-16 which isn't normal around here. We are anywhere between 500ft-1000ft here. My buddies frankenmotor sits at a solid 20 and my brothers 93 leggy turbo also stays at 20. I have retimed the engine 3 times now. And about the vacuum leak I have smoke tested it over and over again and can find no leak. It acts like a vacuum leak. But I cannot find it, if that's the case. Hrmm, that gauge is steady but a little low. Can you do the gauge again while goosing the engine? What is your elevation ( to know for correcting the vac gauge reading )? Have you retimed the engine? The bouncing needle can point to the timing being slightly off or worn valve guides (but usually a little more needle movement) http://www.motor.com/article.asp?article_ID=457
February 5, 201412 yr Smoke test? I always used a hose to the ear to find the leak, if not, a bottle of carb cleaner or spray bottle of water to try to find a change in RPM when the engine sucks in the spray.
February 5, 201412 yr OK, I thought you were gonna say it was the gauge leaking. I have my PC running through a stereo, and the vacuum leak was pretty loud. It sounds like it was close to your camera, so I'd get some carb cleaner spray and start wetting down ALL the vacuum lines where they connect (especially at the throttle body), move the vacuum lines (you might have a split, or rot on a small section, maybe it's touching something hot and poked a hole, etc.) and see if the idle changes or the hiss gets louder. Make sure the car is at normal temp (watch what you spray so it doesn't ignite) so it's not idling high. If you still can't find it, you might have a gasket failure (like the intake manifold, throttle body, etc., so start carefully checking there). Either way, something is leaking and I suspect it might be why it's running funny. If the leak is bad enough, you'll be running lean, which is bad. Edited February 5, 201412 yr by Bushwick
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