I was just running up to the store, got in my car. It started fine, as I was driving, it bucked a bit, like it was going to die, and then ran okay for a little bit longer.. then it shut off. I still had power to my stereo, lights, etc. I pushed it home the few blocks I had made it, and now i'm stuck.

When I crank it, it starts normally, but as soon as I stop cranking the engine, it dies. It does this every time.

Things I know:
It's not the AFM, or at least, it's not the fuel pump switch on the AFM.
Fuel pump works. I can hear it running when I jumpered the check connector.
It's not the battery. The battery cranks it every time, but I have it on the charger now to give it a break.
When it's cranking, the engine sounds normal.
I'm guessing I have spark, as you can definately hear the engine firing when you're cranking.
There are no fuses blown in the engine bay, and the timing is good.
The car ran normally up to this point. It was rather sudden.

Guesses:
Maybe my plugs are defective? (3 week old NGKs)
some sort of key cylinder switch broke/is defective? You can almost pull the key out while the engine is running, if that helps..
???

I'm have NO idea what it is, but I'm pretty sure it's electrical... Please help!

Thanks

 

you sure the fuel pump is still running after you crank the engine?????? Just a thought, but is your ignition switch F'd up and its turning the car off after you let go of it????

 

I already tried cranking it with the fuel pump jumper by the AFM... it made no difference.. crank, crank, crank, vroom, die. every time.. . good thought, though

 

No codes???

Any change while wiggling the ignition switch around? If you have a bunch of keys on the keychain, try it with only one key in the ignition...

 

is there a way to get codes on an S4? I'll check the FAQs... I've tried starting the car about (literally) 40 times... I don't think I can wiggle the switch any more, and I don't have taht many keys on the keychain I'm glad you're here, though, Wayne I need to buy you a beer or something sometime...

 

Wonko, for shame...You don't have the LED setup in the cabin? I think the writeup is on the TEAMFC3S.ORG site. They come in VERY handy considering how often our cars crap out on us

OK, don't burn the starter up, man...Where do you want to start the troubleshooting?

Mmmm, beer

 

I'd still check spark, just to be safe.

 

You just put everything back together, didn't you?

Take a quick look around the engine bay at all of the harness runs, make sure no wiring is chaffing on the engine or any other metal. What kind of shape is that rear rotor housing ground in? Check the security of all of the electrical connectors...

Did you take the plugs off of the ECU during the rebuild?

 

Status report:

Parastie - I pulled all 4 plugs, and turned the CAS by hand to watch the spark.. good spark from all of them.

Wayne - Most of the harness is disconnected, and zip tied out of the way (anything to deal with emissions), Besides double checking the rear ground last time i had the UIM off, It's also reinforced with a piece of 6 Ga wire, so it has to be grounded well

I just had the ECU inside to take a look at it.. it seems like it's good on the inside, no cracks or bad connections that I can see from a casual inspection, no signs of water or corrosion.. I'm on my way out back to make sure it was plugged in tight..

I'm searching through teamFC3S's site now to try to find the diagram for the LED...


Thanks guys

 

It's been so long, I can't remember the exact place place I found that writeup. I have it at home, but that does you no good until I get there at midnight tonight

Hell of a writeup though, I'd like to shake the guy's (or guys') hands who wrote it. This is one of the most important "mods" you could do to your S4, IMO...

 

Double check the AFM connector. A large vacuum hose that popped off will do the same.
I had to chase a fricken problem awhile back after putting the motor together and it wouldn't run. The vacuum hose to the brake booster popped off.
Jumper the yellow connector at the passenger tower and listen for fuel.
It's probably something stupid. Drink a beer and take it slow. Does the tach bounce when you crank the engine?

 

Hey, here it is. I finally tracked it down from links provided on Hugues's site...

http://www.teamfc3s.org/info/article...odes/main.html

 

Wayne - Luckily, my geek abilities have come through again and I happened to have the equipment at home to build this puppy... There's no codes being thrown, however. That's a little bit annoying, it would have been nice (but too easy) if I had know something specific

And yes, I had just gotten the car really running well last week.. The engine was up to par, I had just gotten new shocks and springs on it, took it autocrossing and beat a miata in the rain.. .It was going good.. Was....

boosted1205 - It's not like an AFM problem.. I did have a defective AFM a while ago, what happened with that as that It would start up, run for about 4, 4.5 seconds (with throttle control), then die out. I'm definately getting fuel through the lines, I can feel it pushing through when I jumper that test connector.

The tach does respond normally...

I'm going to see if I can dig up the video cam and record this, might make it a bit more clear..

 

How long has it been since the fuel filters (the inline and the sock on the pump) were replaced?

 

Wyznewski - The inline fuel filter was changed within a year ago.. right before I rebuilt the engine last november. I have no idea about the sock. I can tell you the pump is cycling it through the fuel rails though, you can feel it in the fuel lines if you press down on them..

Here's the video, sorry if it drops frames or anything, it was taken with a poor-*** quality webcam on my POS 366 PII Toshiba Tecra...

http://home.pct.edu/~ebeaar09/outside.avi

Hope this helps diagnose it.

Thank you guys for all your help. I have to go work on a computer for now, sO I probably won't be back for a while, i'll try any suggestions here when I get back if I have the energy, or tomorrow.

Thanks again

~Aaron

 

On the contrary, now you know a big list of things that it's probably NOT

 

wonko, how do you know its not you afm. i have bought parts starters alternators afm and everything else you could think of and had them go bad within a week. (i fix cars alot). even if it is activating your fuel pump if the air fuel mixture is not correct that thing will not run. i would also check the ignition switch. you said that when you stop activating the starter that the engine stops running and thats when you change the position of the ignition switch. i would start with the ignition switch thats probably you best bet.

 

Yeh, bad AFM would probably run a bit longer than that.

Just crap off the top of my head...

The second coil in the circuit opening relay is bad (the one that's energized by the AFM door switch)- jumper the center B/W and Br wires/terminals on the bottom of the relay to test this...

Are any warning lights coming on at all?

CAS wiring- I don't know, that's a stretch...

Vac leak- big one...

Tire pressure in the rear passenger side?- just kidding...That's about all my remaining brain cell can spit out at this point

 

I have no clue. Aaron, if you need parts again, I have an 87 base parts car now. I don't think it's the AFM, since the one I sent you was good. After you crank, does eveything stay in the "On" position(Stereo, logicon, lights, etc.)

-Ian

 

This is gonna sound rather dumb, but is there an air leak somewhere? The symptoms you are decribing are very similar to what mine were when I blew out my ghetto intercooler pipes. The car would do its damndest to start but as soon as I stopped cranking it died. Check all of the hoseclamps and such along the intake side and make sure they are nice and snug. Just my $.02, I know its a dumb solution, but it took me 2 hours 1 day to figure out.

 

Hahahaha I know about that happening. I spent about 3 hours looking over so many different things, but it turned out I just blew off my vacuum line. The hose clamps that come with the car are crap. Easy fix, but I spent all my time looking at everything else that could have gone wrong.

 

jb55555 - I'm fairly certain it's not the AFM, as I jumpered the fuel pump switch and, tried to crank it, no difference, and it's a fairly new (to me) known good one that I got from MolotovMan.. Wayne just suggested checking the coil fired by the AFM switch.. i'm going to check that.

Molotovman - I'm thinking it's key cylinder, but I'm not sure how to check it yet... Everything does stay on though, when I let off the key.. lights, stereo, main engine relay, etc, etc, etc... I may need to hit you up, It COULD be my ECU, I think.. but I don't see how it suddenly died...

Wayne - I know my wheel bearings are shot... I have them on order, would that be close to having low tire pressure? I know the CAS is working, as I teste dthe spark plugs by manually turning the cas, so I'm pretty sure that's out. I'll check the coil when I get home tonight.

jdmsuper7 - I'm pretty sure it's not an intake/vacuum leak, as it happened suddenly, and 20 seconds prior it was idling at a solid 800. It's not turbo so I know I didn't blow out an intercooler pipe or anything..

I'll be checking things out on when I get home tonight, sometime after 8 PM EST.. I'll post then and let you guys know how I make out.

Thanks again!

 

hey sounds kinda like what was happening to me when the hose in the vacume sensor developed a large crack in it.. the car would start up run fine for 1 or 2 sec.. then die!

sounds like your is running for less.. maybe the line just popped off.. mine was still getting vacume i guess just not enough..

i guess just something to check..

also i don't know if you already tried since it doesn't say anyways but check your key cylinder with a voltometer and see if IGN 1 and IGN 2 stay on when you take it off START

I hope you find what's wron Aaron!

Frank

 

hey wonko what did you figure out the problem to be cause i have the same one and it isnt the brake booster like i thought so what was it for you.

 

DemonRX-7 - To be honest, I haven't had a chance to really play with the car since my last post. It's been nuts here! I'm hoping things settle down as finals are over very shortly. I was just arranging to get a new (well, used) ECU and CPU shipped in, and I found one for cheap online today, so I'm hopefully going to get that rockin' soon.. Other than that, I don't know what to tell you... sorry ;(