luna_c666

its on the engine if you read above...

you got any of those ecus lying around??lol

anyways you guys, will the ecu still give out a reference voltage if the ground on the engine is disconnected?

JCurry

iTrader: (6)

where exactly on the engine?? also wat will cause grounds to fry?? like make all the insulation melt off??

thanx

luna_c666

c'mon, man, read the thread...its on the rear rotor housing on the em harness, two bolts I think but its up there, and about your second question, START YOUR OWN THREAD man...this is my problem that has nothing to do with wires frying, at LEAST let someone answer my question before asking another. Not trying to be rude, but I need help on MY car, it's been under for 3 months! Do you own leg work and don't hijack my thread with dumb questions that have already been answered or have nothing to do with my thread..

luna_c666

I'll try this again...

will the ecu still give out a reference voltage if the ground on the engine is disconnected?

HAILERS

Probably not. You don't have to go to the top of the engine and the rear rotor. You can go to the small plug of the series four ecu. Look at the black gnd wires on 3A and 3G. Follow them up the harness. They come together about a foot or less up the harness. Solder a new wire to those gnds where they come together. Attach the other end of the new wire to the bracket that holds the ecu down. That should be enough to gnd the ecu. Key ON, go to a brown/white wire on the boost sensor or afm plug. See if there is four or five volts there. No vdc? Bad ECU. Personally I'd disconnect all five sensors and try looking for the voltage. It's possible one of the sensors is shorted to gnd somewhere.

Probably a bad ECU. It's not that easy to say for sure it's the ecu from this end of a computer with no engine/car in sight. This is just a personal opinion and the knowledge that if the ref voltage isn't being made by the ecu, that the ECU won't work. No way I'm going to depin my gnds on my cars to find out if the ref voltage will be there with no gnds on the ECU. Basic instinct says no.

For the others.....................the ECU gnd on a series four is on top of the REAR rotor housing and about three inches to the left of centerline. One bolt holds two black wires on a ring terminal.

4-5 volts on the brown/white wire of the PRESSURE/BOOST sensor is a good sign. You have no spark. Well ohm out the cas FROM the ECU like the FSM says to make sure the cas wiring is good and check each of those cas wires at the ECU plug to make sure they are not shorted to gnd. That good? Then check for batt voltage at the black/yellow wires at the small white plugs at each coil Assy. Got that? Should have sparked. PUll the cas out or get a spare cas and connect it to the harness. Key ON. Spin the cas bottom gear. The coils should cause the sparkplugs to fire AND the primary injectors to click. Still no spark and no injector clicking? Got me as to why not. If the wiring rings out from point to point and the wires are not shorted to gnd it should have sparked/clicked. Try another ECU. Still bad? I'm out of decent ideas other than it has been found that sometimes the afm will cause the lack of spark if there is a internal afm problem. So you'd just pull the plug off the afm and have a go with spinning the cas bottom gear with the key to On again to see if that helped. By the way, the engine SHOULD start with the afm plug off. The afm has zip to do with Starting. Now keeping the engine running is another thing. You NEED that afm plug on to keep the engine running. IF you tried the above things and they did not cause sparking of the coils.......write your own thread about your problem and maybe someone will try to help you on Your own thread. I'm out of ideas with no car in front of me.

silverfdturbo6port

iTrader: (26)

i dont know i do know that the engine harness is groundedto the block and i have a extra ground comming off the block to the firewall

HAILERS

Your really not catching on. The ECU electronics are powered by a black/white wire and a blue/white wire going into one of the plugs. The electronics INSIDE the ECU also need a ground. Those grounds come out the ECU plugs and mate on the top of the engine.

I'm talking about the electronics INSIDE the ECU box needing a gnd. Put an extra gnd cable b/t the muffler and wiper motor would do as much as adding a extra cable to the firewalll to the engine.

Or how about this. You put the battery in the car. You only connect the positive cable to the battery. You don't connect the negative cable to the battery. Now you go turn the key to START or any other position. It ain't a gonna do a darn thing when you do that. Even if you have a extra gnd going to the block/firewall etc.

I'm not getting thru about this. On to better things to do other than this. Bye.

platinumyama32

ive got a perfectly fine N327 if you need it

luna_c666

Awesomeness dude. What do you want for it?

luna_c666

BTW, thanks for running off someone who was helping ME...
HAILERS: I KNOW WHAT YOU ARE SAYING MAN!
THAT"S WHY I PONDERED MY LAST QUESTION AND I'M WITH YOU ALL THE WAY!

platinumyama32

pm'd ya

silverfdturbo6port

iTrader: (26)

thank you hailers very much sorry for the confusion adn sorry for butting in this thread i figured it all out fine now thank you all

luna_c666

Yay! Forum is back up...
I have an update guys, thought I'd keep you posted for archive's sake. I got a new ecu, tried to fire it up and nothing. Checked ref volage at the boost sensor and there was none, unplugged the AFM and it started right up. Turns out that my 88 style air flow meter was gummed up and stuck closed, once it frees up it runs fine, but after it heats up it gets sticky again and it has hard-start rough idle problems. If anyone knows whether this will burn my new ecu up let me know please before I do that, and if anyone has a spare afm I'm in the market.
Thanks guys!!