ddwelch

Whelp, I picked up a 99 10th Anniversary this past weekend. First Miata I have owned. Been into the Honda scene for ever will my daily for the past 11 years, and my 97 Type R for the last 4 years. I really enjoyed the Miata on the drive home, probably 60 miles. Had some usual used car features like slight vibrations at highway speeds, torn back window in soft top, wear in the interior, etc.

Finally got it home.


Basically the only body damage besides faded clear coat patches.




Milage.


Engine bay.


I peeped under the car as best as I could when inspecting it. Could not really see much due to ground clearance. However, was assured "the car does not have any leaks"... After first night in garage.


No biggie. Will address leak, and in the mean time monitor oil level and carry extra oil in car. Drove the car out to work today, and was planning on taking car to DMV for VIN inspection and registration. Until the car decided not to start at work. So 2 days into this the car leaks, and left me stranded at work. Lol, slightly frustrating but I will pull through. In the mean time I will leave you with the badge number.


Been checking out the forum for a few weeks since deciding that I wanted one of these roadsters. Great place, and looking forward to providing more content of my new (to me) 99 Miata.

Monk

iTrader: (3)

I love a good 10AE.
Did you figure out why it didn't start?

ddwelch

No not yet. I have been so busy at work, which is 30 miles away that I just had to leave it and drive my other car. I plan on taking my truck and trailer tomorrow to pick it up, and then mess with it once I get home. I did stop today and try starting and did confirm fuel pump is not turning on.

Chiburbian

iTrader: (1)

ddwelch

Thanks for the suggestion. I just got the car back home today, and i will start tinkering with it after work and on the weekend.

ddwelch

***Update below picture after I had made this post.

So as mentioned by Chiburbian, I swapped out fuel relay with a new one from Orileys. I also verified main relay (big green relay) in the under hood fuse box worked by plugging it into my friends miata. His fired up just fine with my relay.

Still doing research since these cars are new to me. Any suggestions I should also look into, specific grounds maybe. My friend said to check the ground on the metal bracket that runs front to back next to drive shaft, and ground connection being near the rear differential (picture of mine referenced below). This ground was tight, as he experienced a lose connection there previously that did not allow the car to start.


****Update, found an article about jumping the fuel pump relay which I did from diagnostics box inside the engine bay on driver side. I did get 12 volts to the fuel pump, plugged it it, fuel pump primed when turning key to on position, and car actually started as well. Car will not start with out the jumper in the DIAG box. This was the guide I was following: https://www.miata.net/garage/fuelpumpdiag.html

However, it does not specify what it means when fuel pump does turn on while using jumper. It just mentions that the fuel relay and connections is good, but not the cause of the issue. Any suggestions while I continue to look for more info online? Thanks

Monk

iTrader: (3)

I was going to suggest that you do that, but I forgot.
You need to replace your maf.

ddwelch

Thanks for the suggestion. I will try to find one from a buddy to try out before buying a new one and hoping it works. I will update when that happens.

SpartanSV

AFAIK AFM preventing the fuel pump from functioning should be 1.6 only.

If you have a multimeter start by confirming you don't have power at the pump. Work back from there.

ddwelch

I also forgot to add that I also did steps 6a-6c from the guide https://www.miata.net/garage/fuelpumpdiag.html. I get the 12v from the other two wires (not the blue/red or light green) as mentioned in 6a. Moving onto step 6b I get constant continuity to ground from light green wire while having key in the on position, even when not having the key in the crank position at all. Does this mean a relay else where is staying shut, incorrect signal from AFM, or worst case potential short somewhere in line?

Moving onto step 6c I also did that check, and I do not see any voltage from green wire to ground when turning key to crank position. I think this is being caused from the constant grounding I am seeing in step 6b.

SpartanSV

Main relay supplies power to one side of the coil in the fuel pump relay. The ECU is suppose to provide ground on to the other side of the coil, via the green wire, to switch the relay and power the pump. Any time the green wire shows continuity to ground the relay should be triggering and powering the pump via red/blue.

Check for power at the red/blue wire when the fuel pump should be on. That would be either while cranking or check for a short pulse when the key is cycled on. Have the fuel pump relay installed in case it wasn't obvious.

ddwelch

@spartan Sorry if I missed it, but I do not have 12v at pump. I took my main relay and tried it on my buddies NA and his car fired right up. So then I decided to swap out the fuel pump relay with a new one, and that did not give me the 12v. From my understanding jumping the FP and GND in the diag box sends the 12v through the fuel pump relay, and onto the FP. Which it does (I think that meant my relay was good).

I am seeing both the 12v at the terminals from the main relay.

I did mess up when measuring the continuity to ground on the LT Green wire... I had jumper wire in diag box when measuring that. Took jumper out and no ground signal from ECU.

ddwelch

This thread is exactly the same issue I am seeing, but there was never a resolution posted.
https://forum.miata.net/vb/showthread.php?t=313147

SpartanSV

K so the pump runs when you have the jumper in? Then yes the ecu isn't supplying ground to trigger the relay. I would measure at the ecu next. Pin 3N light green.

ddwelch

Update!

I would not say I fixed it, because I did not actually measure or swap anything that caused it to work. In the link posted 2 threads above someone asked, what happens when you start the car with jumper? Which I thought was a very good question. I went out started car with jumper, pulled jumper and car continued to run. Turned car off, cranked over again and viola! It started finally with out the jumper. Maybe sometime in the next couple days I am going to throw original fuel pump relay in to actually verify if that was bad or not. Right now I am on new pump relay and it seems to be working as it should.

I appreciate everyones input, and eager to start driving this beast as intended.