Okay, so I'm trying not to freak out. Earlier today, I was doing a freeway pull in my '99 single-turbo FD either 4th or 5th gear, low boost, I think around 1.2 bar. I'm not precisely sure where my boost controller cuts out, but my car died with no bang, no noises, and no cloud of smoke. Now it cranks but won't start but the compression sounds good. It's acting like my Fiat did when I had a crank/cam error. The AFR was around 12, the crankcase oil level was good, the temp was just over 80°C, and I was premixed a little over 1:100. I haven't tested anything because this happened as I was on my way out of town for a 7's Day event. Any help would be greatly appreciated.

 

Motors don't always blow in a grand fashion. Sometimes they die just the way you described. Do a proper compression test and go from there. Troubleshoot just like any other car: air, fuel, spark

 

I hope you are aware that for year '96 and newer, Mazda changed the mounting order of the ignition coils. This can result in mechanics hooking up the spark plug leads and/or coil harness in the wrong order.

Although this may result in rough running at low speed, at revs around 6000 , or higher, engine detonation can occur.

 

Yea once I get home I will.

 

This thread has some discussion of the coil position issue:

https://www.rx7club.com/3rd-generati...1169041/page2/

 

When I get home I'll throw a bore scope in it to check out the internals too.

 

Did the car sit for a long time recently? Did you just fill up?
It is remote, but you may have bad gas. And now maybe you are flooding the motor.

 

I don't thing it's hooked up backwards but I'll check.

 

so i compression tested it and compression is decent but all 6 faces were equal so i have less anxiety now lol. I had just gassed up with gas from the Costco and premixed but also just got my Sohn adapter so it probably had a fair bit of premix in the fuel lol. it hadn't been sitting for more than a few days because i took it to a car show like the Sunday before this happened.

 

We spend some time troubleshooting my friends Version 3 RHD. Swapping in TPS, ISC, MAP etc.

The car could not hold idle and would stall out as soon as you took the foot of the gas.

He reported to me yesterday that they discovered water had gotten into the front relay box.

(it had been mounted upside down, when a single turbo set up had been installed.)

Car runs fine now.

Also he swapped out his older generation Power Fc for a newer Haltech.

 

You used a proper rotary compression tester, right?

 

i used a regular compression tester but zip tied down the release button and recorded it because i didn't have access to a proper one but i could see all 3 pulses individually on the video, i want to upgrade ecu's that's just a rabbit hole i cant afford right now.

 

"zip tie down the release button". I have not heard of that hack. Seems like a simple solution.

 

sometimes you got to work with what you got lol XD

 

Does the car have stock or aftermarket coils? I ask because if it has an aftermarket setup you could have had the fuse for the coils blow resulting in an ignition cut.

You've tested compression and thinks it's okay. Check for spark and fuel, if the coils are fine your fuel pump could have died.

 

Our big issue was we overflooded the car. And everytime we did a deflooding (12 times) we still over flooded the car. That is why we went with removing the ISC and letting the engine suck in a ton of air. As there seems to be some redundancy in the fuel pump wiring circuit, when we started the deflood process, we unplugged the fuel pump harness connector at the fuel pump end. To avoid over-leaning the mixture, once the car started, the tech used his hand as a ISC valve until we could get the ISC valve back on.

My injectors may have been leaking and thereby contributing to the flooding. I subsequently got the injectors refurbished (C$550). They were tested to be running at 65%.

When you crank the engine is there a lot of fuel smell in the exhaust?

 

I posted this elsewhere recently, but here we go again:

 

yea spark is next i forgot to mention in the chaos of everything but i am getting fuel pressure to the rail, i finally have use for the fuel pump switch that the previous owner installed XD. i got stock coils but ill go through and check everything.

 

not really and the afr reads good for idle after start. ill run through the deflooding procedure a few times and turn it over with no plugs and the pump off to try to get out any excess fuel thats in the housings.

 

After so many attempts to start, we figured the engine was hopelessly flooded. Hence the drastic action.

Coils could show some spark, but the spark might be weak.

Remember my warning about the hook up order of the stock coils for newer FD.

After trying many things, we decided to give the gas a sniff. Very little gassy smell.

Changing out the entire tank and purging the bad gas in the system then became the first step toward getting the motor restarted.

(The bad gas possibly came from Cherry Point....where does Costco get their gas?)

 

If you don't have spark, proceed to check continuity on the wires for the crank angle sensors. If you're not getting a signal to the ECU it won't output spark.
I just spoke with another FD owner over the weekend whose car was dead after two years of storage. He diagnosed it as a no spark issue that was caused by a broken wire at a CAS connector, other owners have experienced similar issues.

 

Correct....we rcently had a no-spark issue that required re-pinning all the connectors at the CAS....problem was intermitant making it hard-to-find....30 yearold connectors often ware out.

 

i havent checked spark yet my dad was gonna help crank it while i check for spark but he tripped and messed up his ankle so he spent most of the day at the hospital getting it looked at so while i was waiting for him to get done i made some models of Keisuke's FD that i got this last weekend. i havent had any hard times starting the only weird thing its done is sometimes after i come to a stop after cruising it doesnt want to idle so i have to give it the tiniest but of throttle.

 

ok so update it doesnt have spark. also my coils were hooked up correctly from what i saw.

 

ok egi fuse has continuity figure thatd be my next check lol