idle bouncing...

try starting the car with the IACV pipe blocked off on both sides and see if that makes a difference. If it behaves better change out the IACV with new one. dont bother trying to clean it.

 

i would try a different ecu, or a different tune, and yeah that is wierd for it not to have the light.

 

also make sure the ecu plug is tight

 

also could be a bad or faulty fuel pump/FPR. Check to make sure everything works ok, and that fuel pressure is at 42 psi

 

The only ECM's with no light that I know of are 97-98 blacktop ones. Those ECM's cannot be chipped either to my knowledge. Who rom tuned your ECU and what is the code on it?

 

its code 62 with no dio light, can anyone else verify if this would be a problem or not.?

im going to try and swap out my entire fuel rail and regulator.
question, with the nismo fpr, if i remove the vacume from it..what should happen? motor dosent seem to respond at all...

 

its code 62 with no dio light, can anyone else verify if this would be a problem or not.?

im going to try and swap out my entire fuel rail and regulator.
question, with the nismo fpr, if i remove the vacume from it..what should happen? motor dosent seem to respond at all...

No, your ecu sounds like the one I pulled from my car (redtop 62) when I fried a 12v terminal and had an electrician jump the burnt connection. I had no led light so he just soldered in a new led light and I got my error codes and everything just fine after that.

If you remove the vacuum line from the regulator at idle (no boost) and you have the tb port capped off (so there's no vacuum leak), you should notice nothing since the fuel pressure is set at 43.5 psi and increases only with boost. Your fuel pressure would not increase past its set point, and thats all.

 

i just received a set of 550cc injectors i will swap them in, along with a fuel pressure gauge to check if the nismo fpr is working.

but i was thinking long and hard... Idle Air Control
how can i test for a bad IAC? makes sense right? could a bad IAC cause these problems?

plz keep ur brains thinking for me..

 

Holy shit! did you not read my post?

 

a fp gauge is crutial to dial in your nismo fpr.. that could be why its dumping fuel in. do you have a walbro fuel pump?

 

on the nismo fpr, (and almost all fpr's) backing the screw out is less pressure right? cuz its always been all they way out.. yes i got a warbro

joel- sorry man, i don't know why i didnt read ur post..., just prof that im loosing my mind... im just going to pinch that line closed, if their is no change then the IACV isnt working right?

 

you might have to remove it and plug it with something as the hose is pretty stiff usually and you wont get a tight enough seal.

pull the hose of the cold piping and block it with your palms or use a cork or something. Make sure you block both the hose and the flange openings.

If the idle steadies (may be a little high though) then replace the valve with a new one. Otherwise its something else.

 

question, why would it stabilize? dont u think if i blocked the IACV, and it was faulty the motor wouldn't respond.

--THINK IM GETTING CLOSER, the fuel pump doesnt go on at all... i started testing wires. when i ground out the body harness's Black w/pink striped (fuel pump relay) wire the pump turns on.. but never shuts it self off. (switched relays, same problem, pump wont turn on..) checked fuses ok, what color is the power wire going to the pump?

i check all my injectors.. no leaks, got a fuel pressure gauge hooked up.. set my FPR to 42 (just with key on) nismo regulator worked but very sensitive adjustment.

I WILL send some one 15 bucks if they come up with the answer to my problem.. (via paypal)

 

If you pull the vacume line off the FPR the idle should dip a little. If it's not responding then check the FPR and your vacume connection to it (make sure if you put your finger over the line you feel suction).

After that, my bet is on the ECU although I supposed the IACV could be at fault as well.

 

check for boost leaks, make sure your bov isnt stuck open either.

Is your ecu plug tight?

The wire that powers the fuel pump is black/yellow

Did you try a different ecu yet?

Is your IACV screw opened up all the way? Check that

Will the car stay running if you open the throttle?

ecu gives the fuel pump ground, ecu also shuts off the fuel pump, soooo if you ecu is messed up or the plug isnt tight it could cause this to happen.

also check all your grounds for the engine harness and ecu

 

-no leaks, good vacume
-IAC is working ( when i pinch the hose closed the car stumbles and dies out)
-The car stays alive, no problem, and rev's up nice! just runs PIG rich (10.0) with fuel dumping out the exhaust, stumbles at idle.
-ECU plug is tight, and perfect.i have a known bad ECU i plugged that in still no pump came on. (just a shot in the dark)
- i noticed when i turn the key on, i get no power to the pump BUT i do hear it make 1 small "thump" sound..i get 10 PSI of fuel pressure at the line.. can this be my problem?>!@!@!!????? doesnt make sense how low fuel pressure would make a car run rich.
it is a known good fuel pump. im getting no power to the pump, only power to the level sender..good fuses and relays...

aaaaaaaaaaahhhhhhhhhhhhh im loosing my mind...

help?

Chris

 

try putting a known good ecu in it

you will only have power to the pump when key is on and only for 3 seconds unless the engine is cranking, then you will lose power to it.

You say you have good fuses and good relays, did you check the wiring for the pump?

do this, give the black/yellow wire 12v just hook it straight to the battery, and give the pump ground anywhere you can, its ok if it runs constantly for testing purposes.

I would make sure your ecu is getting power and actually turning on also.

Make sure you wiring is all good from your initial swap.

its wierd that you say it runs, but the fuel pump isnt turning on. Then how the hell does it run lol

 

i no, its very odd..
im a perfectionist everything i do has to be done the right way. so no wires are rigged together.
-i can turn the pump on by grounding out the black and pink wire (with my test light) on the brown body harness (the one used with the swap)
i kept it grounded and the pump stayed on.. pumping 42lbs. then started it up... nope same out come..10.0...

 

is the maf grounded right try grounding it then ungrounding and see what happens if it clears up the dumping or not did for me. i had it grounded forever got a retune ecu then ungrounded and it worked fine. i had the same kinda problem u did seems like at least..

also its hard to understand u hows the car stay alive and rev if the fuel pump doesnt work ?

 

i think he means the pump comes on when the engine is started. so the ecu is tell the pump to come on just the ignition isnt telling it to prime? no clue. but are you serious? you ungrounded your z32 maf? the ground to the chassis?

 

yeah i know what your talking about, that one ground wire on the MAF, some people say ground it to the chassis others say connect it to the harness ground. i think its port C on the z32 maf. these maf sensors are stupid like that... its worth a check.. ill pull it apart tomorrow. I ran a ground to the chassis by the way...so u want me to just pull it off?

as for the fuel pump problem.. lol... im f*cking clueless,

aaaaaaaaaahhhhhhhh i miss my car....


thanx guys, keep my brain thinking..

chris

 

It's a problem with the MAF. Either bad MAF or bad MAF wiring.

Get it fixed and I'll give you my PayPal addy.

 

Agreed^^^^^^

Sounds like the maf is the only thing you havent really fucked with....

This thread is just another reason why i love using standalonez! Fuck all the extra wiring and fucking mafs!!!!

 

just checked all my MAF wiring (for the 3rd time) and tried a different z32 maf (thats number 5)
Same effect,
tried disconnecting maf ground.. no difference.. im gunna try and get a new ECU...

 

After you realize that it actually is a problem with the MAF or MAF wiring I expect to collect on that $15.

Oh and here is a quick test for you. Start your car. When it is idling unplug your MAF. Did the idle change? I bet you it doesn't which signifies a bad MAF or bad MAF wiring.

 

It's a problem with the MAF. Either bad MAF or bad MAF wiring.

Get it fixed and I'll give you my PayPal addy.

wow dude obviously u cant read and are in need oh 15 dollars badly i had posted above you about the maf so ur a lil late and u cant just say its a problem with the maf, fix it and give ur ass credit! get the fuck outa here ! your unbelieveable

 

ahhh, i drove the car, put about 10 miles on the motor, it was FINE for one entire day.... its not the wiring

then started crapping out... yes i understand it sounds like a MAF problem. but i been through 5 MAF sensors!!!!!!!
is there a chance 5 maf's could be bad.? Yes.. but 3 of them are known to be good and are running in cars right now..

 

I love the response when offered a reward of $15 haha.

I just read over your original post and thought about it. You say there's no fuel pump sound when you first turn the key, and for the first 20-30 seconds the car runs pretty darn lean. Then it suddenly goes pig rich then dies.

Try this: Have someone stick their head in the trunk, and put their ear against the fuel pump assembly. When you turn the key to "on" it should be on for a few seconds, just to pressurize the fuel lines. If it doesnt go on, something is wrong (i'll get to that). Then start the car and have him listen to when the fuel pump actually DOES turn on fully.

Because from what you describe, It seems that initially the car is running super lean from essentially residual fuel pressure in the fuel system. The ECU is trying to compensate for that by running the injectors at 100% duty cycle, so when the fuel pump actually does turn on, it floods the heck out of the motor and you eventually sputter and die.

The fix (if this is actually what is going on): Fuel pump relay could be old and dying, the fuel pump itself could be old and dying, the fuel pump switch on the internals of the ECU could be faulty, or the wiring/ground could be bad. OR it could just be a REALLY messed up fuel map, which switches from super lean on cold start, to super rich when warm, but check the fuel pump stuff first.

 

-I never said the car dies, it doesnt die at all.. it stays alive and revs perfectly. But at idle it runs PIG rich dumping fuel out of the tail pipe. (lots of smoke) and a 10.0 a/f ratio and all my plugs foul out (dry fouled)
-the fuel pump puts out 42psi, when the motor is running,

THE REAL FIX... I NEED A KNOWN WORKING ECU. (if that works then ima send myself 15 bucks)

this is how my maf is wired by the way..(as of now)
http://srownersclub.com/faq/faq_mafs.asp

 

I know this is gonna sound dumb but have you checked your alternator voltage, one more thing maybe bad ground on ignition coils.(maybe weak spark)No ,I dont need the money...

 

hold on gangster chris read the 3rd post down from the beginning of this thread.

try an ecu posted by me

let me know if it fixes it, dude i could tottaly use 15 bucks.

 

we could all use the 15 bucks, but i can find an ECU, to check with.
looks like im stuck getting an ebay one..150 bucks.. damn it..