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Pretty sure my car is possessed by evil demons


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11 replies to this topic

#1 Hondasucks

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Posted 22 May 2013 - 10:21 PM

So I started poking around my car (87 GL turbo), looking for anything obvious, found one of the injector bolts was broken off on the driver's side. Got the broken bolt out and replaced the injector seals on that side, still ran like rump roast. So I poked around some more, and found that the intake boot had come off the turbo, so I stuffed it back on and tightened the clamp, and in doing so discovered that it had a huge crack in it, right above the clamp. So I dug through my parts shed and found a good boot, was off a flapper door style MAF equipped car, but since it's shorter it works better with my cone air filter anyway. Made sure it wasn't cracked and put it on, got it all tight and all the lines hooked up, and it still runs like rump roast and has a funky idle. 

Compression is good, timing is good (both valve and ignition) alternator output is good and steady (The voltage gauge does jump around when the blinkers are on, etc.. but the voltage at the alternator stays steady, and this car has always done that as long as I've had it)

 

Cylinder #4 misses at idle (Was both 2 and 4 before I replaced the injector seals)

It does run better than before, and it goes like a scalded dog when it's cold but once it warms up it falls on its face unless I keep my foot out of it. Under higher boost (7+ lbs) it will start to cut out (Feels like the ignition shuts down for like, 1/2 second or so, about the only way I can describe it, occasionally it will backfire out the intake but seems to not do it anymore since I replaced the tube) but if I keep it under 2-3 psi it seems to be fine, and it has plenty of go off-boost. I've got a few theories:

 

1) it's got a bad knock sensor (I haven't tried putting a resistor in place of the coolant temp sensor to see if the problem is related to the actual temperature of the engine, or if it's related to what the computer thinks the temp is) and it starts dumping garbage data when it warms up, causing the computer to pull timing

 

2) It's leaning out, causing it to detonate, causing the computer to pull timing

 

3) It's got carbon deposits or a hotspot in the cooling system, and the excess heat is causing detonation, causing it to pull timing (Doesn't run hot or make noise or anything gauge wise)

 

4) Bad MAF sensor?

 

I'm not quite sure how to test the knock sensor without a scope, and I'm not about to just bypass it and have it be #2 or #3 and I melt a hole in a piston, but the knock sensor looks like a whole barrel of monkeys to replace... Might have to just pull the manifold next time I'm in Albany and replace all the vacuum lines and such (I did this when I put the new engine in my SVX, found like 3 cracked vacuum lines under the manifold... Tempted to just put the old engine back in [Nothing wrong with it, the guy I bought it from had a shop replace the flex plate, and they replaced it with a 4 cylinder flex plate, which shredded on the freeway, picked up a 60k motor for $100 and thought I'd just throw it in, turns out it has a dead hole... So now I gotta pull that one back out, replace the timing belt, water pump, and seals on the old motor, and drop it back in... And I can't do that until I finish the body work on dad's Mustang so we can sell it.. Ugh, too many projects, not enough time!  :banghead:  :banghead:  :banghead:

 

 



#2 TOsborn

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Posted 23 May 2013 - 12:29 AM

Regarding your knock sensor, unplug it and see if the problem persists.  Theoretically it doesn't have to be installed for the car to run, as all it does is pull timing when it senses a knock.  Try unplugging the sensor by the bellhousing, probably don't unplug the whole knock control unit.

 

Also, if your interested, I found this page very helpful when I was researching how EA82T knock sensors work, lots of good information:

 

http://www.ausubaru....ead.php?t=11260


Edited by TOsborn, 23 May 2013 - 12:47 AM.


#3 djellum

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Posted 23 May 2013 - 12:46 AM

assuming that you checked spark and ignition condition, did you check fuel pressure and/or flow?



#4 scoobiedubie

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Posted 23 May 2013 - 09:48 AM

If either of the 2 boots between the intake manifold and the turbo, have loose clamps, it will fall on it's face when it warms up.  The boots will get soft with heat, and allow the pressurized air to escape.



#5 ivans imports

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Posted 23 May 2013 - 10:16 AM

perty shure all subarus are posesed by the devel in you right foot !



#6 ivans imports

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Posted 23 May 2013 - 10:18 AM

check feul preshure reg those years were bad for rusting out the inside of regulators and not making enuff preshure also check timing

#7 AKghandi

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Posted 24 May 2013 - 02:08 AM

I had the same issues, I have a video from when it was doing it, i started with the CTS,then the intake boot, then the MAF, and that fixed it. You'll want to ignore my talking as I was still trying to figure out what was wrong with it, this will mainly be to see if your car is doing the same thing. It was a real head scratcher, took me around a month to figure it out.

 

this was when it was just starting to do it, it slowly got worse and worse till it would just barely drive. 

 

Mine was very sensitive to leaks, i actually had to seal my intake pipe with RTV

 

 

 

http://www.ultimates...-of-assistance/

and this is the thread from then.



#8 Caboobaroo

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Posted 24 May 2013 - 11:09 AM

Andrew, give me a couple weeks to get back down there. I have a spare EA82T MAF in my toolbox plus some other bits to try. I will be down this weekend but doing other stuff, might have time to chat.

#9 Gloyale

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Posted 24 May 2013 - 12:25 PM

Andy I've got a slew of EA82t parts.  Spider intakes, set of new injectors, MAFs, ECUs, CTSs, etc...

 

Let me know.  I missed your PMs last week.  Are you gonna be down this week?



#10 Hondasucks

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Posted 26 May 2013 - 10:09 PM

Won't be down this weekend but will be down next weekend. I've checked the fuel pressure, put a gauge on it, ran the hose up under the edge of the hood and duct taped the gauge to the windshield and drove it, fuel pressure was spot on. 

 

As for unplugging the knock sensor, it's an 87 car with an 88 engine, the knock control is built into the ECU instead of being the separate module like the older cars, and the knock sensor is buried under a sea of PCV lines, I have thought about unplugging it though... Russ and Austin looked at it today and Russ was pretty convinced it's the coolant sensor, and since it's $15 and mine is corroded to hell, even if it doesn't fix it, it definitely needs one.



#11 ivans imports

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Posted 28 May 2013 - 09:27 AM

To check knock senser gentaly tap on block next to senser with a bar and see if idle drops if so knock senser is working



#12 Caboobaroo

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Posted 29 May 2013 - 03:22 PM

I also think that collapsed lifter on the #3 intake valve isn't helping either...

Try unplugging the MAF and see if it runs better. My roommates 1UZ swapped 4Runner had a bad MAF and it was causing all types of run ability issues. He unplugged it, ran better but ran real rich, as the ECU now had substituted it's own value in for the MAF.
Worst that might happens is the gas mileage is worse then it already is but might drive better.




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