I'm totally confused
08-01-2010, 01:49 PM
#1
Intrawebz Wizard
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Join Date: Feb 2009
Location: Vernal, UT
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I'm totally confused
This Z is being extremely odd. I fixed what I think is wrong with the harness but now the ECU wont ground the relay to the coil anymore. the wire is fine all the way to the ECU and the ecu is no longer putting codes out other then the ok code. I jumped the relay myself and the z misfired and blew TONS of black smoke.
Do I have a fried ECU or a grounding issue from hell? or something else entirely?
EDIT: I just checked all the grounds. ECU engine everything. their all fine! So is the ECU fried???
Do I have a fried ECU or a grounding issue from hell? or something else entirely?
EDIT: I just checked all the grounds. ECU engine everything. their all fine! So is the ECU fried???
Last edited by BlueKitsune; 08-01-2010 at 01:56 PM.
08-01-2010, 02:41 PM
#3
Intrawebz Wizard
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EGI and IGN coil Relays are not being triggered by the ECU even tho the connectors, relay, and wires to the ecu are fine. ECU has no fault codes. when I ground the relays manually the engine runs but stumbles, searches for an idle, will not go over 2K rpm and will die if throttle keeps being held down, and smokes black smoke like mad.
the ecu harness is "ok" with no shorts or opens in it tho its a rats nest now. and the PTU MAF, CAS, coils, injectors are all ok.
EDIT: Just tested the fuel pressure. 50 PSI peak (first second on and cranking) 41 PSI when off and its being held.
the ecu harness is "ok" with no shorts or opens in it tho its a rats nest now. and the PTU MAF, CAS, coils, injectors are all ok.
EDIT: Just tested the fuel pressure. 50 PSI peak (first second on and cranking) 41 PSI when off and its being held.
Last edited by BlueKitsune; 08-01-2010 at 02:56 PM.
08-01-2010, 04:14 PM
#4
Intrawebz Wizard
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pins 10 20 50 60 107 108 and 116 are grounded properly. and i checked them many times. along with any items they connected to with the ground. So The only thing left that I can think of is the ECU is bad but not tossing a code.
08-01-2010, 04:44 PM
#5
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What I mean to say is, WHAT WAS THE CAR DOING TO PROMPT YOU TO INVESTIGATE ANYTHING AT ALL?
Was it simply not running at all? Was it running like ****? What?
It sounds like the car simply wasn't running, but I'm not going to start doing any diagnostics until I know what the hell the symptom was. I don't care what diagnosis you've already done, yet. lol
Was it simply not running at all? Was it running like ****? What?
It sounds like the car simply wasn't running, but I'm not going to start doing any diagnostics until I know what the hell the symptom was. I don't care what diagnosis you've already done, yet. lol
08-01-2010, 04:51 PM
#6
Intrawebz Wizard
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I said in the first post. But, it wont start unless I ground the coil and egi relays so their on. after its running it is constantly searching for an idle speed, along with smoking black smoke. Then if I use the gas it with either nearly die and catch itself or outright die. but it will never go over 2K rpm.
Sorry. my brain is a bit fried I've been working on this Z for 6 hours straight.
Sorry. my brain is a bit fried I've been working on this Z for 6 hours straight.
08-01-2010, 05:01 PM
#7
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You NEVER said it would not start, you said
and
Do you know any local Z owners with similar specifications from whom you could borrow their ECU for a test? That's a lot of things wrong to be caused by anything smaller than the ECU, so I'm inclined to say it could be the ECU itself.
and
Do you know any local Z owners with similar specifications from whom you could borrow their ECU for a test? That's a lot of things wrong to be caused by anything smaller than the ECU, so I'm inclined to say it could be the ECU itself.
08-01-2010, 05:34 PM
#9
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Go to TwinTurbo.NET, select Pages, then Members, then Directory Search. Look for people in Utah, make sure to ask it to return the date of the last login. Find any members who have been recently active and email them to see if they can swing by to test their ECU in your car (or vice-verse).
The ECU really isn't throwing any codes with those symptoms?
The ECU really isn't throwing any codes with those symptoms?
08-01-2010, 06:47 PM
#11
Intrawebz Wizard
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turns out the owner had a spare. but it was an NA one... we tried it and the car started and idled fine. so yes it is the ECU. I'm not looking for a new ECU. Anyone got one for less then $500....
PS: no I wont drive on the N/A ECU
PS: no I wont drive on the N/A ECU
08-01-2010, 07:22 PM
#12
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Good boy.
Email Specialty Z or ZTuner and see if either of them can either send you a chip to swap into the NA ECU (not 100% sure if this is the best route, as it may still not be able to make proper use of the TT's 3-speed fuel pump - ask about this) or will accept the NA ECU as a core on an upgraded TT ECU.
SpecialtyZ.com
ZTuner.com
Email Specialty Z or ZTuner and see if either of them can either send you a chip to swap into the NA ECU (not 100% sure if this is the best route, as it may still not be able to make proper use of the TT's 3-speed fuel pump - ask about this) or will accept the NA ECU as a core on an upgraded TT ECU.
SpecialtyZ.com
ZTuner.com
08-01-2010, 07:26 PM
#13
Intrawebz Wizard
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Well before I go buying the wrong ECU I should give the full specs of this Z
1990 300ZX 2+2
auto trans, JDM Twin Turbo swap
Auto to 5 speed swap.
If the full pump has been changed, I have no clue w/o pulling the pump to check. so I'm betting its still using the stock n/a pump. idk if they changed the harness either. but i noticed the harness has 2 out of 3 prongs on the TPS plug and the TPS itself has all 3 prongs.
1990 300ZX 2+2
auto trans, JDM Twin Turbo swap
Auto to 5 speed swap.
If the full pump has been changed, I have no clue w/o pulling the pump to check. so I'm betting its still using the stock n/a pump. idk if they changed the harness either. but i noticed the harness has 2 out of 3 prongs on the TPS plug and the TPS itself has all 3 prongs.
08-01-2010, 07:57 PM
#15
Intrawebz Wizard
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Alright. Thanks!
Now to install an oil cooler, fix the reverse light switch, fix the knock in the suspension somewhere. install an electric fan or 2, and fix that DAMN detonation sensor! the n/a ECU thew the code for it.
Now to install an oil cooler, fix the reverse light switch, fix the knock in the suspension somewhere. install an electric fan or 2, and fix that DAMN detonation sensor! the n/a ECU thew the code for it.
08-01-2010, 07:59 PM
#16
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FYI regarding the detonation sensor, it's often the harness, so make sure to replace that as well.
What kind of suspension knock?
And electric fans don't work well on the hot-running Twin Turbo... you're best off with the belt-driven fan.
Good luck.
What kind of suspension knock?
And electric fans don't work well on the hot-running Twin Turbo... you're best off with the belt-driven fan.
Good luck.
08-01-2010, 08:21 PM
#17
Intrawebz Wizard
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The front passenger side makes a weird knock like something is loose every once in a while.
And I cant get to the bloody harness. Unless I pull the intake or something. thats why I put a 1K ohm resistor across the contacts with the detonation sensor. but that apparently didnt work.
And I cant get to the bloody harness. Unless I pull the intake or something. thats why I put a 1K ohm resistor across the contacts with the detonation sensor. but that apparently didnt work.
08-01-2010, 08:48 PM
#18
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I was never a fan of the resistor trick... I just grounded the bitch out when I had trouble with it.
http://twinturbo.net/nissan/300zx/FA...ges/sbfix.html
And the click could be the king pin... I had the same problem (does it happen during low-speed turning?).
http://twinturbo.net/nissan/300zx/FA...ges/sbfix.html
And the click could be the king pin... I had the same problem (does it happen during low-speed turning?).
08-01-2010, 09:07 PM
#19
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lol interesting trick. but someone already deleted the actuators and put in a manual boost controller ( I know I know but it wasn't my idea and I told them to change it)
It happens randomly at best but It does seem to happen with low speed turns.
It happens randomly at best but It does seem to happen with low speed turns.
08-01-2010, 09:15 PM
#20
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Decreasing the boost is not all that happens... you still don't want it retarding the timing (which reduces power), so the sensor/harness either needs to be replaced or grounded out to prevent it.
08-01-2010, 10:26 PM
#24
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I'm argued out for the day... this happened on TwinTurbo.NET earlier (summed up on ChicagoZ.com):
http://www.chicagoz.com/forums/showp...0&postcount=14
http://www.chicagoz.com/forums/showp...0&postcount=14
08-02-2010, 04:01 PM
#25
Intrawebz Wizard
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Well I figured out the ECU issue. It was a Mine's Motor Sports Creator modified ECU with a 93 TT Auto prom in it.
the owner chipped it with an ebay 90 TT Manual prom.
Thankfully the old prom was saved and I'm going to send it off to get the prom switched back.
the owner chipped it with an ebay 90 TT Manual prom.
Thankfully the old prom was saved and I'm going to send it off to get the prom switched back.
