my interesting predicament
 

i get to right to the point. my car will start rev to 1000RPM then die. no matter what i do, every time it will rev up then just die. i use my fuel cut it will do the same thing. and it will start just fine, but rev then die.


this is what i have done so fair:

fixed all wires going into the ecu. (so like any mods that were done from about 10 inches away from the ecu, everything is now stock)
tried a few diff ecu
tried different coils
new plugs
new spark plug wires
new fuel filter
new fuel pump
played with the bac valve a bit
charged the battery
and a few more

but anywise. i need help. any other ideas on what it could be? HELP!

MAF... make sure there is a small black rubber hose connected to your intake tubing (big black tube). if it's not connected, the car will start, rev, die. Maybe your MAF sensor is bad?

yea i have checked the maf seems to be alright.

but ill see if i can find another one to use..

yea i would try to get another one out of a runnin FC, cuz thats what they do when you unplug them .....UMMMM BAHHH, that has to be it

Sounds almost exactly like what happens when the fuel pump switch in the AFM dies. Try this for me once: on the passanger side shock tower, somewhere underneath the pressure/boost sensor, there's a yellow, two-socketed connection in a black rubber housing. short that out once. when you turn the car to "on" you should hear the fuel pump.. er... pumping (it will be a whirrring sound in the engine bay). Try starting the car. If this is the problem, then your AFM is bad, start looking for a replacement.

^ "Jumper" the 2 prongs in the yellow connector on the passenger side strut tower with a paper clip, wire, or a piece of solder with the ignition in the ON position. Check the resistances on your AFM. The test is in the FSM.

yea i have dont the yellow 2 prong trick already

currently working on the maf. ill let you guys now. thanks for the help!

maf is fine.. could it be the crank angle sensor?

If the MAF is fine perhaps it's just a massive vacuum leak?

all the vac lines are fine aswell :(

Um... I hate to say this.... You're really not going to like this. In fact, just scroll past this post.



This sounds like the same problem I was having that caused me to get pissed off enough to rip out all of the factory wiring and install a MegaSquirt.


the ONLY thing that I could come up with was that the primary injectors were somehow shorting out or something, causing them either never come on (after the initial crank injection), or to flood out. but I never had too much backfiring with it (mostly ruling out B), and I never actually got a good way to rule out A. It would reliably turn over and rev, EVERY time i turned the key. Good luck with your diagnostics. I'll try to help as I can.

yea i am thinking its the harness aswell

really dont want it to be. but i cant think of anything else it could be.

either the AFM has been messed with (the cap is missing and the screw tampered with) or the AFM switch internally has died or you have a big leak in your intake duct, once the vacuum has stabilized the leak takes flow away from the AFM and the pump switch closes.

another possibility is that your fuel cut switch is faulty.

Did the pump stay constantly runnnig?

yes it did.

Basic troubleshooting for non-running engine...

It's either fuel or spark.

Troubleshooting spark is easy.
Pull spark plug wire from spark plug end and place it close to a known ground point.
I use the strut tower studs, since it's convenient.
Pop the black rubber cover for the top of the struts and place the spark plug wire ends nearby.
It helps to have a friend.
One person crank the engine, while the other watch to see if they are all sparking.

Fuel is a bit more involved.
WARNING: YOU WILL BE SPILLING GASOLINE SO KEEP ANYTHING FLAMMABLE (i.e. throw away the cigarette) AWAY - if you have been checking spark as described above, make sure the reinstall the spark plug wires appropriately!
Since only the primary fuel injectors fire, you need access to them.
You got a turbo?
The intercooler and upper intake manifold have to come off - there's no way around it.
Secure the primary fuel injectors to the fuel rail - I used nylon wire / zip ties or lengths of wire laying around.
If you don't secure them, they will pop off and shoot fuel all over the place once the fuel pump primes! :(
Once secured, remove the two bolts that hold the primary fuel rail in place.
You might have to also remove the upper / secondary fuel rail, as this helps to reposition the primary fuel injectors so that you can see them shooting fuel out the ends.
Crank the engine and you *should* see alternating squirts of fuel from the fuel injectors.
If you don't, you know it's a fuel problem.


-Ted

right on. i panned on taking a look at my fuel injectors today. so ill try that aswell.

thanks for the info.

I know you've checked the MAF, but how about its connector? Mine was slightly loose, recently, and had exactly the same symptoms as you described.