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Help diagnose what went wrong

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Old 12-16-2009 | 11:25 AM
  #101  
NismoPick's Avatar
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How would you know it's "lacking torque" if you haven't floored it? Obviously easing onto the throttle isn't going to give huge amounts of torque.

Also... on a turbocharged motor, a straight dump pipe is about as good as it gets for exhaust. You want ZERO back pressure after the turbo.

And a 3k break in is way too long...

Easy for 500mi, do oil change.
Easy for 500 more mi, then you are good. Oil change @ about 1500 mi to synthetic.
Old 12-16-2009 | 12:32 PM
  #102  
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dude your a *****!!!! lol. it is NOT THAT LOUD. and also, you can give her some juice after its up to temp and a few miles of normal driving. still wouldn't go full throttle. after 500 miles you can give it WOT a few times, like through a first gear pull or a second gear pull. but you don't want continuous WOT on it. remember to change the oil frequently (i did 500 mile intervals till i hit 1500 now i'll be going back to 3k then maybe switch to synthetic) and use conventional oil. after 1500 miles i will give the fudger full throttle as long as i want. if you baby an engine to much during break in it might last 300k but it won't make as much power as if say you gave it quick minor beatings periodically through the break in. Hell you could do a motor break-in doing nothing but WOT and it'll work AMAZING but it won't last long. gotta compromise. don't be a puss basically. and 3k is way overkill for a break-in period. just remember the oil and to let it warm up before driving. fresh engines shouldn't be driven cold.
Old 12-16-2009 | 12:37 PM
  #103  
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w0rld's l0ngest m0t0rswap
 
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Originally Posted by snwbrderphat540
dude your a *****!!!! lol. .
stop internet-bullying me.... ;P yeah i'll break it in good enough, but its got some pretty weird popping when i decelerate, and i have to adjust my AFR, but yeah right now its able to go up and down the street but boy it sure is lacking that umf
Old 12-16-2009 | 07:50 PM
  #104  
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my car popped allllllllllll the time while letting it engine brake. its common in any car with a full exhuast/lacking an exhuast. hell mine would sometimes make a fun backfire with a neato flame and set off a car alarm if you pushed it really hard then let off real quick (its the random mix of AFR the car isnt expecting mixed with the open downpipe situation) once i got an exhaust on that, it did it no more.
Old 12-18-2009 | 10:13 PM
  #105  
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i just want to say: driving has never kicked so much *** DDD
Old 12-19-2009 | 01:35 AM
  #106  
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what does that mean?
Old 12-27-2009 | 09:58 PM
  #107  
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w0rld's l0ngest m0t0rswap
 
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i seem to be having an issue with the '76 tachometer and my 82 ignition coil. I had the tachometer running a few times (although it would read around 400 rpm more ) and now its not sending any signal. I figured I should replace the resistor and what i can gather is that I want a 6.8k ohm resistor (http://www.zhome.com/rnt/L28conversion/engine.html) or a 2.5k resistor (from a thread i was reading by mhinrichs who has done the identical swap. Anyways, what the hell is it?? Should i just try 2.5 and then 6.8? the fsm for the 260 says "This tachometer is a voltage trigger type" which to me might as well say "娱乐、体育、文化和社会新闻,并提供电邮及即时通信服务。主要服务北美"

oh and i made some pretty sweet IC mounts this weekend!
Old 03-04-2010 | 08:06 PM
  #108  
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so i've been getting about 2 miles per gallon with my new swap and now i have run into another problem:

My oxygen sensor is reading lean at .20 volts at idle, with throttle still no change at all.

I spent 2 hours adjusting one 2 teeth on the AFM in each direction 18 teeth and testing each one, consequently i found that 18 teeth (yes eighteen) richer gives me really nice power but still a .20 reading. Then i accidently left the 02 sensor out and i still got a .20 reading from the ECU. wtf???
I have tested this narrow band sensor using the propane torch method and it does reach .9 volts and taking away immediatly leans it out to .1 v

SO! Those are the facts. I have tested continuity from the 02 wire to the ECU and it reads 100% continuous, and I have even tried 2 different ECUs with the same exact results. So, gentlemen what do i try next?

Could CHTS give me lean readings? What else should I be testing? I have done a resistance test in boiling water with the CHTS and it passed, but I have yet to check continuity to the ECU...I'll do that tomorrow...

in the meantime im gonna go trip on alice in wonderland 3D
Old 03-04-2010 | 08:09 PM
  #109  
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if the CHTS goes bad you get a very rich mixture. and how are you getting a lean reading when you claim to be getting 2 miles per gallon? which is totally impossible the car would run like **** if it was able to use that much fuel.
Old 03-05-2010 | 02:48 AM
  #110  
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Originally Posted by snwbrderphat540
if the CHTS goes bad you get a very rich mixture. and how are you getting a lean reading when you claim to be getting 2 miles per gallon? which is totally impossible the car would run like **** if it was able to use that much fuel.
i dont know!!!!!! that's the thing!! its so mystifying that somehow my mileage is 2mpg and i'm reading .20 across all the AFM settings!!!

If the 02 tests good, and the continuity to the ECU tests good how is it getting a reading of .20v across über rich AFM settings???
Old 03-05-2010 | 09:12 AM
  #111  
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Okay does it makes sense: if the 02 sensor is saying lean then the computer will rich the mixture, and if it keeps reading lean then it will keep enriching the mixture, right?

i got it: the ECU is running in open-loop. Why is it stuck in open loop??

Last edited by thetremendousti; 03-05-2010 at 10:12 AM.
Old 03-05-2010 | 11:33 AM
  #112  
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Solution:

Jack up radiator cap. Park new car under it.
Old 03-08-2010 | 11:04 AM
  #113  
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i felld offa mai trike
 
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^so win.
Old 03-16-2010 | 11:10 PM
  #114  
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WELL 8 months later:

Oil in my water. Again.

I've decided to sell whatever I can of this cursed car. I mean I rebuilt the goddamn engine, I don't know what else could I be doing wrong. I think there is a crack in the block by the 3 & 4 cylinder oil passage. I was thinking of locktiting the head bolt's threads but that would only delay the inevitable. Anyways...It really is a shitty feeling. I'm making a list of parts that I could possibly sell and then idk what to do with this shell, Z's were fun...sort of...
Old 03-17-2010 | 12:07 AM
  #115  
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very hard to crack a block. i'd suspect the head if anything.

hey what kinda pistons did you use again? n i forgot, were they forged or cast?
Old 03-17-2010 | 12:28 AM
  #116  
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just cast. yeah the stock head i got had a corroded head bolt hole, and also the head bolt was corroded. also the inside of the cylinder walls (3 & 4) were oddly corroded but i flex honed them out. The head I had on just now was decked mirror flat so i dont know, and i dont want to know i just want to get this off my hands
Old 03-17-2010 | 12:49 AM
  #117  
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its kind of ironic though, first i had oil in my water, now its water in my oil. no milky-ness just distinct coolant in the top of my head (right as you take VC off) its not too mixed either...
Old 03-17-2010 | 08:15 AM
  #118  
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parts car!
Old 03-17-2010 | 09:13 AM
  #119  
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Damn!!!! I woulda took those pistons otherwise. Jerk
Old 03-17-2010 | 09:28 AM
  #120  
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Before you give up on the car, do more tests. If I were you, I'd rig up some kind of pressure kit & test the cooling system for leaks.

If you do part it out, I got dibs on the injectors!
Old 03-17-2010 | 12:07 PM
  #121  
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ill take your interfooler setup.
Old 03-17-2010 | 12:11 PM
  #122  
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he sounds like he has givin up so everyone shut up!



n sell me your front mount setup. oh yes oh yes...

btw what sorta intercooler is that. im sure the piping/couplers/and clamps are generic. but no big, hope you didn't completely skimp on the intercooler. if so i'll take just the piping. please and thank you.
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