OptionXIII

If I were you I'd re-do those mounts somehow. Miata engine mounts are hardly known for strength and it looks like you welded on the backside of a metal plate with rubber bonded on the other side. I wouldn't think that is good for the rubber.

ajay842

The welding instructor dunked the mount in water several times while welding it. Not good for the weld but it kept from melting the rubber.

That's the only mount like that and it's the stock Starlet mount. The others I have poly bushings and steel tubing for.

ajay842

I also put the starlet radiator in it and let the engine run for awhile. I needed to flush the coolant anyway. It's nice to see the car shake as the engine idles.



So all the welding from now on is mine.




It's cramped by that motor mount.










Anyway, today was finally the day. I was able to drive it.

I finished the trans mount, welded the driveshaft, finished the clutch, bled the brake and clutch, and a bunch of little things.

It's fun to drive, really fun to drive. It's way too loud though, I need to get some more tubing on it and quiet it down a bit. I was wearing some ear muffs and it was still too loud in the cab.

Otherwise first gear is hard to get traction in(it was wet though) and second gear hooks pretty good. Got up to highway speeds, 5th gear about 3k rpms and there wasn't any obnoxious vibrations. (Guess my driveshaft jig worked) Couple of small ones but they were there before .

Anyway, time for pics.








Welds weren't as good as I wanted, but my welder was acting up and that's the best I could do. (It hasn't broken yet!)

I fixed a bunch of vacuum leaks, coolant sensor (ecm thought it was -40C!) and alternator plug and went for another drive. About halfway through my driveway the engine starts bucking acting like it's starved for fuel.

Eventually I realized the afpr is failing(?) If I ran the pump it would hold fine for a few seconds at 58psi, then make a strange noise and the pressure would start to drop and hover around 10 psi.

I towed the car back home and took the afpr apart. The diaphram wasn't tore or anything. I put it back on the car and tried it, held fine at 58psi for atleast a minute.

Not sure if it really is bad or not?

Maybe there was a peice of crud stuck in there holding it open?
Seems like it was a clogged filter, hasn't happened since.

I've been messing around with it trying to fix little problems. I put the starlet wiring back in and now I have taillights again. I also welded some more exhaust in so now it's tolerable, still loud but not near as bad.

Also grabbed a video of running and pulling in the garage.








And before you say anything, yes the brake lines are going to be moved, no the radiator is not staying, and no, the vice grip battery is staying. It's called a quick release battery terminal.




Alright, diagnosis time.

2 issues right now.

Surging idle
If I unplug IAC problem goes away and idles fine around 850 rpm.

When warmed up, engine revs to 2k and back to 1k. Repeats this behavior.
I took a vacuum gauge and I am getting 20 in/lbs at idle with the iac unplugged (to get steady idle)

Scanner shows 9% throttle when no throttle is applied. TPS shows clean sweep from .5 volts all the way up to 3.8 volts. (??? off maybe)

Surging revving
If I unplug TPS, this problem goes away.

When idling or driving (when driving it bucks) if you press the gas less than 1/4 throttle and hold it. Revs will hold for a second and drop to around 1k, and then back to before.

ajay842

Sorry, totally did not mean to double post.

I'll use this crap post to update, turns out the high idle was caused by the neutral switch. As soon as I plugged it in, nice closed loop idle.

ajay842

So I've been driving it around lately, so far so good. Some little kinks I'm working out but the engine wants to live.

There's one problem that's a headscratcher, randomly, if I get on it and get up to 4-6k it'll peter out and lose power. Sometimes it really pulls, and others it peters out. I believe the fuel hardline is 5/16, possibly not enough flow at higher rpms?

Other than that I put a muffler on it, Wix Miata fuel filter, and a brand new Denso Miata radiator in it.

ajay842

Just found the build thread section, sorry I posted this in the wrong section. If a mod could move this to the correct build thread section, that'd be great.