99 Miata Engine Replacement

Popped a CEL on the way to work. Pulled the code and it looks like my wire extension for the rear O2 sensor failed somewhere along the line. It's reading a steady 1.2v regardless of what is going on, threw 'voltage high' code. It wasn't that was initially, so I'm guessing the vibration or heat messed with the wiring somewhere. Going to fish it back out and see tonight.
 
Well, leaving my work parking lot, the Miata just suddenly shut off, and won't refire. It cranks, I have full electric power, but just won't fire.

I'm leaning toward a fuel problem, though what specifically I don't know. My boss gave me a ride home, headed back up there with my wife and the 8 (and tools/gas) to see if I can solve it. I didn't get any stumbling before it that would suggest running out of fuel, and the gauge reads 1/4 tank remaining. Granted, it could be 1/4th of water, but if I did have that much water in my tank, I'd expect problems before now, considering it's heavier than gas and I've driven 110 miles since the engine replacement.

Fuses and pump are my next two possible options.
 
Since I have full electrical power and it cranks fine, it isn't a ground or battery/alternator problem, leaving me with fuel delivery or spark creation after the alternator.

With my tools, I will be able to verify spark and fuel pump.

Just found another possibility, the crank angle sensor, which (considering where it is and how it's mounted), I could see the possibility that the bolt loosened up and it finally drooped downward around the bolt, leaving the physical distance it needs to be in (to the crankshaft pulley) and thus killing spark and fuel (same way a disconnected e-shaft sensor kills our spark/fuel). Will be the first thing to check. Also have a 2nd sensor from my original engine that I will bring with me.

After that, on to the fuses. If those show fine and still no start, then verify I'm getting ignition, then getting fuel. If I'm getting ignition and fuel and it's cranking fine, then I will have a running engine :)

Not even a cough of trying to fire tells me there isn't a mid-way failure, like a dying coil or clogged filter. It's a simple and complete interruption of one or both.
 
My rear O2 failing harness shorted out and blew the engine 15a fuse. Took an hour and 4 fuses to figure that out.
 
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good work dude! i was hoping to go to the auto x on the 10th but i have a work party that afternoon....
 
If the only thing is the PS delete I wouldn't worry about CSP and run as STR, unless you beat me then I will complain! If you are not planning on running at any National Events who cares the P/S delete and motor mount isn't going to make that much of a difference. If R-Comps are in your future then CSP is the class but staying on Streets then STR is fine.


Should be able to make it to Renegade next weekend (9/10), probably the last 2 events too.

Need to examine the rule book to see where I will even class as now :)

Edit:
Since I'm not sleeping at the moment anyway, was poking through the rules. Modifications are:
- Motor Mount upgrade (STR legal it looks like)
- A/C Delete (appears to be stock legal? There is a clarification for Stock in the Appendix, but says nothing about STR, and first reference in the main rules is in Street Prepared)
- Power Steering Delete (Only mentioned in Prepared, so only Prepared legal?)
- Removal of CA spec header cat and upgrade to Jackson Racing header (appears to be STR legal, if it's a 'conversion', which the only point I could see being a sticking point is if someone objects to where I ran the rear O2 sensor wiring, as it is apparently different than OEM 49 state legal, or that I don't have the FED sticker under the hood. I am emissions compliant in all new england states)
- Upgrading OEM cat to high flow cat (appears STR legal. Visually they look identical, so I'm sure it meets the 'same size and location' rule. Still emissions compliant, no codes, no codes hidden)

Plus the cat back and front sway bar that I know is stock legal.

So does the power steering delete put me into Prepared? 99's were possible with a manual rack I believe (even if insanely rare), so I'm guessing I would have to convert to that original trim across the whole car to be STR legal. Including that impossible to find manual rack. I'm going to expect that it's actually a disadvantage for tight Renegade courses. Enjoying it quite a bit for the street though.
 
Yeah, likely just running Renegade in the foreseeable future. Discussed it with Marc, and while I am technically not legal for STR, the items to get legal are all improving the performance through weight reduction (leather seats, Bose audio, power windows and locks etc converting to a completely base model), getting the Manual rack (which is again a performance improvement), and finding a FED emissions sticker for the hood.

It was possible to buy a 1999 Miata from the dealer with no PS, though PS was defaulted on every possible package, so it would have had to be a barebones one. So if anyone complains, then they would be complaining that I am not as competitive as I could be (because of ~10-40lbs of added weight). The other parts of those packages that matter (diff, wheels) are upgrade legal in STR.

The whole "letter of the law" vs "spirit of the law" debate :)

I'm not going R-comps, and long before I mod up everything else to get STR competitive I will shift to not being legal for STR anyway. I'm not building for a class, I'm just building for what I want to drive. I just don't want to be flagrantly flaunting a rules violation.
 
If I remember right, power steering and A/C were actually options from the factory but not really options. I did some research and everything I came up with on the '99 said that those two things were considered options and not "standard equipment". Just like 6speed said... Any package added it on, but you could technically get a '99 Miata without either from the factory.

It's like paint on cars that is an option but really isn't an option.
 
Yeah - Just running with Renegade I don't see a problem, nobody is really going to care. If you run with NER then you will definely have to run according to your upgrades. Run awhile in STR, make your improvements then get R-Comps and go CSP.

JUST DON'T BEAT ME!(sad1)(sad1)(sad1)

Yeah, likely just running Renegade in the foreseeable future. Discussed it with Marc, and while I am technically not legal for STR, the items to get legal are all improving the performance through weight reduction (leather seats, Bose audio, power windows and locks etc converting to a completely base model), getting the Manual rack (which is again a performance improvement), and finding a FED emissions sticker for the hood.

It was possible to buy a 1999 Miata from the dealer with no PS, though PS was defaulted on every possible package, so it would have had to be a barebones one. So if anyone complains, then they would be complaining that I am not as competitive as I could be (because of ~10-40lbs of added weight). The other parts of those packages that matter (diff, wheels) are upgrade legal in STR.

The whole "letter of the law" vs "spirit of the law" debate :)

I'm not going R-comps, and long before I mod up everything else to get STR competitive I will shift to not being legal for STR anyway. I'm not building for a class, I'm just building for what I want to drive. I just don't want to be flagrantly flaunting a rules violation.
 
Yeah - Just running with Renegade I don't see a problem, nobody is really going to care. If you run with NER then you will definely have to run according to your upgrades. Run awhile in STR, make your improvements then get R-Comps and go CSP.

JUST DON'T BEAT ME!(sad1)(sad1)(sad1)

Go ahead and beat Bob. I love to hear him whine.
 
I think beating Bob will entirely depend on the rain content of the track :)

The first SCCA this year showed how good these street tires are in the rain.

I will be there for Renegade tomorrow, so we will see.
 
Whinning! I would rather call it a form of high pitched annoying voice of displeasure.

To which you have elevated to a high art.

I think beating Bob will entirely depend on the rain content of the track :)

The first SCCA this year showed how good these street tires are in the rain.

I will be there for Renegade tomorrow, so we will see.

Good luck. Just don't let Bob in the car with you.
 
I didn't beat Bob.


However, I did let him ride for 1 run.

He didn't make me run for any cones while I was working, though, so I'll let him pass this time :)
 
Mike -

The car sounded and appeared to run great. Nice Work! Oleg is the one to watch right now, he is driving great and putting down some fantastic times. This pass Sunday (Porsche Club) I believe he was 8th in Raw Time against all those porsches. He beat the crap out of me! I felt like Bruce when I beat the crap out of him.
 
Thanks. I did get that one misfire during the runs, but it hasn't been repeated. I also have some light load valve rattle still, nothing is making it go away, including various oil weights. Nothing severe, but enough to bother me a bit.
 
So, this engine might be toast already.

Miata.net thread on it: http://forum.miata.net/vb/showthread.php?t=434865

Basically, the Mid Ohio trip brought to my attention that my Miata is burning a quart of oil every 300 miles. Not 800 like I thought at Mid Ohio, which was still high. It was consistently 300 miles on the trip to MD and then back home to RI. Did some digging for info, and then pulled apart the UIM/LIM, and it's quite a bit more oily than I would expect (they were completely clean when I finished the replacement). Might have bought an engine with failed piston rings. Don't know what I am going to do about it yet. Going to keep driving it for the immediate future, switch oils and additives and such to see if I can reduce consumption, but the near future is uncertain.
 
If I replace it, I can join the "3 engine club" on rx8club.com, but with my Miata.

[ironic]Doing the rotary swap would net me more power, more reliability, and less oil consumption.[/ironic] :)
 
wow mike, i'm sorry to hear this. i know how hard you worked t get that thing up and running.....any idea if the seller willl stand behind the motor?
 
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