SprungMS

Long story short, I rebuilt my turbo 1.6 over the last week or so, and the last couple days, I've had timing hell. I've redone valve timing 10ish times, and all I've achieved is a "close to starting" position. It sounds like it's going to catch, and then dies out. Ignition timing is perfectly 10* BTDC. The cam gear marks are lined up with the marks on the seal plate at TDC, other than the intake cam being shifted one tooth retarded to help reduce valve overlap. Spark in all 4 cylinders, nice strong fuel smell, it has to be timing, but who has tips for how I can set it?

viperormiata

iTrader: (24)

I had this issue when I tried my first start up after my supercharger-uninstall due to a mangled wire coming off the CAS. Not saying that is what your issue it, but it was something out of the ordinary that I didn't even think to check.

Before you try and to crank it again, do a check over of everything.

taocle

http://revlimiter.net/blog/wp-conten...9/DSC_1797.jpg
i found that picture really helpful maybe double check that you didnt have intake and exhaust line up mixed up like me

flounder

.....

SprungMS

I actually had this problem months back, and I rewired the sensor completely after replacing the sensor itself. The motor ran fine after that until a few weeks back when I spun a rod bearing. Because of that problem, the first thing I did when it didn't start was check to be sure that all of that wiring was fine.


Yep, some kinda genius huh? Same thing as putting an adjustable cam gear on it and adjusting it to 6* of retard. Also, I set ignition timing while cranking to 10* BTDC after the change, so it wasn't affecting the ignition timing. However, this morning I did rotate it back one tooth the other way, set ignition timing again, and it still won't start.

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Update: I pulled spark plugs today, #2-4 all were black on the tip of the electrode with fuel. #3,4 had black on the threads of the plug. #1 had absolutely no black whatsoever on any part of it.
I have sprayed carb cleaner in the pcv hose port on the manifold, so I still don't think this is a fuel problem. I think I have a 22-year old wiring problem. My injectors are wired for sequential injection, and I am running that really old "MiataLink" version of Link Engine Management. I'd love to switch over to MS or really anything else, but I just spent a good 2-3k in this rebuild, and I'd like to leave that upgrade for somewhere down the road when I can actually already drive the car.

flounder

Do you have the coil leads switched?

SprungMS

I thought of that, but I never removed them when I took everything apart. I removed the HT leads from the plugs, and unplugged the connector going to the coils. Then just took out the bolts securing the coils and removed them like that. They went back in the same.

flounder

Sorry, I have a bad habit of calling the connectors "leads". Are you sure the connectors are back on the correct coil and that the plug wires are in the right order?

SprungMS

Yes, I've checked the order, but I also did not remove the HT leads from the coils at any point. I only removed them from the spark plugs.
News though. I did a compression test... 140-60-75-100. Then a leakdown test.... Only I can't tell where the air is leaking to. I think it's going out the intake valves, but I think it could be going out the exhaust valves as well. Any thoughts? I couldn't find a procedure for adjusting valve lash... The machine shop assembled the head, minus the cams, and I installed it as returned to me.

SprungMS

Oh and the connectors... There is only one connector that goes to the coils, and it's plugged in. The connectors in the back were never removed.

Compression has to be the problem at this point. I just can't figure out why it has such bad compression in those 3 cylinders. I think the next thing I'm gonna do is loosen up the cam caps so that there is no pressure on the HLAs, and then compression test again. I figure the cams must be pressing down on the lifters some all the time or something... Although there is no way to manually adjust valve lash on this engine. Frustrating situation. I'm a Honda guy. Some of this Miata stuff is new to me.

Savington

iTrader: (31)

Take your valve cover off, set the motor to TDC, and photograph the timing belt, cam marks, and camshafts.

SprungMS

Too late for that. Taking the head back off. My valves are staying open with the cams out of the head. Most likely bent, I just can't figure out how that could have happened.

SprungMS

Okay... Updates, if anyone can help.

I compression tested it before the head came out to go to the machine shop again. 140-60-75-100. I got the head back from the machine shop yesterday, and worked all day putting everything together. Tried to start, wouldn't start. Turning over quickly like it wants to. Bought a compression tester today finally, and I'm a little confused about the results. 120-95-100-120. I did reuse my head gasket, but only because it was brand new when I put it together the first time, and it never actually started. It came out of the car looking new, of course compressed some. I torqued the ARP head studs 5lbf ft more than before.

Does anyone know anything about compression test readings? I've never had a rebuilt engine have no compression without it being timing that's wrong.

Oh and that. Timing is perfect, I've read everything online there is to read about setting 1.6 cam timing, and with my 1 tooth intake retard, there are 19 teeth between the 12 o'clock marks on the cam gears.

Please help. I want to drift.

tpwalsh

That's more than enough compression for the motor to at least start. You've got something else going on. Not enough fuel? Too much Fuel? Spark? Spark at the wrong time?

SprungMS

My iPhone keeps deleting my posts. This is staying short.

I put oil in all the cylinders and got 180 in cyl 1, then 190 on a second try. Put all the plugs in, put wires on, and cranked it. It fired and turned over for about 1-2 cycles. Then waited for a few minutes, and tried again. It started after a few cranks, and ran with my foot tapping the gas to hold it at about 2k. After about 10 seconds it died. Mad smoke out the exhaust from oil on pistons. I went with a friend to trade his wherls for Si wheels.

When I get home this is my plan: put oil in cylinders, compression test all 4, if they're all good, try to start it again. It ran really rough when it did start, but I kind of expected that on the first start.

Anyone have suggestions? Why the rings wouldn't be holding compression? I'm damn near positive I installed all of them correctly.

SprungMS

So I may have messed up a cylinder. I did the oil thing again, but this time I cranked it for the compression test and heard a pop. Then the #1 cylinder put out a good strong 20 psi. I took the tester out of the cylinder and turned it over and I could hear somewhat of a scraping or more just a moving noise. Very slight. I waited a couple minutes and cranked it again and the noise was gone. My next step will be to remove the pistons and rings, and make sure they're installed correctly. My manual says the middle ring has its groove facing down. Is that right? I believe that's how I installed them.

SprungMS

You guys forget about me..?

Good news! Well kinda. Got home from work, added about a half-cap of engine oil to each cylinder, and compression tested it. 15x across the board. #1 as well. I think I have another problem. This is my normal engine start scenario... I turn my ignition on, and wait until my fuel pump cuts off. Then I crank it, and it starts on the 2nd crank.
Only.. Right now, my fuel pump stays on all the time. Never cuts off if the ignition is on. I have used GND and F/P in the diagnostic connector to cause the pump to run constantly, but never noticed any noises under the hood or anything.. Well, right now I hear fuel running through my FPR. I don't think I ever could before, but I could be wrong. In any case, my AEM wideband is reading --- all of the time, which is the most lean it could read, basically means it doesn't detect fuel. Occasionally, it would alternate between 14.5-15.5 and ---, depending on the rotation of the engine.

I am running that old Link Engine Management "Miatalink". I have sequential injection wired, and I've never had a problem with fuel before.
I really think that this can be fixed without pulling the pistons. I'm so sure I'm gonna spend all day taking my engine apart only to tap the pistons out and see all the rings perfectly installed and staggered. I really do think that I'm not getting fuel. Don't smell any in the exhaust.

Ah, keep thinking of things. I've seen a very very slight bit of blue smoke trailing out of the exhaust, and a good amount blue smoke comes out of the breather on the valve cover. I would suppose that's just blowby, especially with the amount of oil on my pistons, but just figured I'd mention it.

Could really use someone to bounce ideas off of here, as you can probably tell. I kind of have a one-sided conversation going on in this thread...

tpwalsh

Sounds like you've got a fuel issue. Any idea what your fuel pressure looks like? Are your injectors clicking?

flounder

What did the machine shop say about the stuck open valves?

If you have to consistantly add oil to the cylinders to get respectable numbers, something is wrong. Who built it, and are there pics?

SprungMS

Getting a FP tester today for that purpose, and I have no idea if they're clicking. I haven't had a helper since I've been messing with the fuel system, and even with my remote start, it's loud as **** in my garage just with the engine turning over. Also, I don't have a stethoscope in the house, which is ridiculous. My dad is a doctor, and my mom is a pharmacist, both of whom own their own businesses. Ridiculous.

The machine shop didn't say a damn thing. They suck. Parts didn't even come back as clean as they should have. There were little tiny metal specks like glued into the head. In the cambox of course, not combustion chamber, I have a feeling they aren't going anywhere though.
I took the head back to the shop, and honestly, I just assumed it was that the valves were staying open. I put pressure to the cylinders and I could feel air coming out of the PCV vacuum hose from the IM, but at this point I think I may have imagined it. I know I could feel air coming out of the other spark plug holes, and I thought it was because the pressure was leaving one cylinder through the intake valves, then because of the limited space from the throttle plate, the air was going back through the other open intake valves and up through the combustion chambers. I think what really was happening is the pressure couldn't go past the valves, and it was going straight past rings, pressurizing the crankcase and pushing air out the other cylinders via their ring seats. Which I'm not exactly worried about, I think they need to seat first. Again, I could be wrong. And I have not put pressure into the cylinders since I got the head back from the shop, I've only compression tested it.

EDIT: Just saw that second line. I built it, with the "help" of a friend who has built 8 or 9 Honda engines with me. I've never had to use oil in the combustion chamber to get better compression numbers, but even dry, it should be starting. Dry compression was looking like 100-120 psi. Which is clearly not good, but it's good enough. I've been thinking if I can get it started for any length of time, the rings will seat better than they have so far, and boost that number. I've only been using oil as a supplement, if it can raise my compression by 40 psi on a half cap of oil, I should REALLY be able to start it. Didn't take any pictures myself, but I know my friend did, I have no idea what he took though. I know he didn't take pictures of installed rings. The hone marks in the block are great, the factory hone marks were still showing when I picked this short block up.
I have never built a Miata motor before, and I feel like if this thing was on a stock ecu with a stock wiring harness, I'd have no issues, I think it's just not happy trying to fire with my current EMS settings. So I'm going outside now to try to start it with starting fluid, and also run another round of compression tests dry and wet, before adjusting my cold start settings in my ECU.
I pinched my return line at about 3 this morning and cranked it over a few times, immediately my WB gauge was at 14-15.5. It wasn't even reading that it saw fuel before I pinched the line, so I have a feeling my FPR is leaky, which is what compelled me to buy a pressure tester. If I get no good results right now working on it, I'm gonna go pick that tester up, and test before the rail with and without pressure to the vacuum port on the FPR.

Also, I HAVE done my research, hours and hours of it, about the miata in particular. I am positive that nothing is wrong with the cam timing, the crank pulley and harmonic balancer are brand new. Ignition timing is to spec, and there is good strong spark. I changed out my new 2 step colder iridiums for stock heat range coppers for now. On my ECU's keypad, RPM registers in at 500-550 cranking, which means my CAS signal is good, and it is freshly wired. Those are the things I'd tell someone else to check for if they had this problem. Well other than the fuel delivery issue.