Just rebuilt my Miata's motor. Everything seemed to be okay until I cranked it and she didn't fire. What could be the problem? I believe all the fuel lines are hooked up properly. In fact the only fuel line I disconnected upon removal was this fuel line with the white marker, pictured here: http://www.freeimagehosting.net/uploads/d53b1b4017.jpg
That hooks up to the hose on the left going into the oil filter hub right...? (the motor is upside down, normally that hose is on the right)
She sounds normal turning over. She's been sitting there for months so I tried putting in a gallon of fresh gas but that didn't do anything. Common wisdom deems it's a fuel or spark problem...ideas, guys?
I'm guessing that this is a 99? Did you connect the crankshaft position sensor?is it within spec? If it is a 99 I doubt that the fuel lines are screwed up.All the grounds on?
The crankshaft sensor is on, I don't know if it's in spec. I've heard it's 4 Visa cards worth of clearance between it and the pulley, but I don't know if it's even on the right way. This is what we're talking about right? http://www.freeimagehosting.net/image.php?b0ba5a7fc0.jpg
rev, I don't know which fuel lines I would swap because that line with the white connector is the only one I ever disconnected.
nev, I'll have to check that.
Do I have to spray the starting fluid in the intake manifold or can I just spray it in the snorkel? Last time I tried starting the car without the plastic intake, the car wouldn't start, I'm assuming because the MAF was unplugged.
Wait, Which way do you have the coil packs plugged in? There are 2 plugs, 1 for each pack, If you have them plugged in backwards the coils will fire back wards.
The coils were labeled by the previous owner with R and L, I plugged the R into the pax side...I could try switching them around and see if that helps. Knowing how my car was mistreated, I wouldn't be surprised if the previous owner labeled them incorrectly.
If they are labeled R and L, I would bet they are labeled in respect to how you see them from the engine bay. Check a haynes manual and match up the wiring colors with which cylinders those colors signal. Or just swap and see what happens.
I checked the spark plugs by grounding them. Neither the third or first spark plug sparked, which means neither banks of coils are doing their job. I've been trying to reverse the coil plugs but I've tried for hours to unplug the plugs, but they're so far back in the engine bay it's near impossible for me to release them. Those release tabs don't do a very good job of releasing. I'm definitely getting fuel though, as I can smell gasoline after I crank it for awhile. (and there isn't any gasoline on the floor, lol)
If you cannot get them unplugged swap the plug wires. I am not sure which but from the factory one of the plugs should have blue tape on it. I think it goes to the passenger side.. Ill find out definately monday but just switch the plug wires to fire as if the coils are plugged in backwards
I do believe one of the plugs has blue tape on it. Lemme know when you figure out for sure which way it goes. Even if they are reversed though, would it really not let the car spark at all?
one coil is supposed to fire 1-3 and the other one 2-4 so that says that one of them is broken or not plugged in correctly. even if your timing belt was off they'd still all spark
The way you wrote the spark diagnosis part it sounded like only 1 and 3 werent sparking. If none of them are sparking then you're probably not getting a CAS signal. check for fuel too.
The crank angle sensor on a NB is fairly dummy proof to install. The air gap is a wide margin. If you can have a buddy help you verify spark on all four cylinders and firing in the correct order. If the timing was way off you would have no compression. Since this is a recently rebuilt motor I would check compression if you havent already. Fuel pressure is there if you can smell gas and odds are the engine is flooded pull the plugs see if they are covered in fuel if so put a small bottle cap of atf down the the spark plug holes to bring compression back. New motors take a while to fire up the first time. Dont worry man you'll get it going. Hope this helps any more Q's feel free to ask.
If you have inj. sending fuel then i would think it would be a crank or cam sensor... also means your ecu is reading the signal... double check grounds make sure they have a clean surface and making good contact... if you can get your hands on another set of coils i would swap them out...
Took it to a shop to diagnose the problem. They found it that it was indeed the crank sensor. I had checked it before and it seemed to be fine...I have no idea what they did to fix it. The air gap seemed exactly the same. I am also going to have to get some new spark plug wires. I didn't know it before but the wires that the previous owner put on the car are NOT intended for a Miata at all. Also, I think the shop stole my intake manifold support brace...it was on before I took it there lol. I'll have to go get that back. Thanks so much for the help guys! She runs great, she was idling funny and not holding revs (stalling at a stop) for the first few miles, but now everything's golden except I've got a small coolant leak I haven't been able fix. But that's for another thread. Oh, and the RB header + Springfield Dyno exhaust creates beautiful noises. I highly recommend the header, I can't wail on the car yet (break in period) so I can't tell you what my butt dyno reports, but the fitment was great, the quality is top notch, and it looks and sounds beautiful.
One more thing: my car spits fireballs when it after-fires now
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