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strangest symptoms, ea82T 1988


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so its starting, but not staying running,   ive got the timing set correctly, belt and distributor,  20 degrees btdc with the green test connectors. every sensor is oem, all the connections have been cleaned, so.. could this be bad ecu?

i just tore the distributor apart and cleaned the pickup wheel (it was dirty) reassembled and its still having the same issues

https://cdn.discordapp.com/attachments/794993406040211477/803799186386452500/video_2021-01-26_17-29-57.mp4

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Charge light is just the field flash circuit of the alternator and indicates if the voltage potential is higher at the battery or at the alternator. If they are the same (battery charged and alternator operating) then the light goes out because there is no potential. Doesn't matter either way for operation of the EFI - the EFI can operate down to about 5v and as high as 16-17v by design. The ECM has to be live when cranking and in the case of a marginal battery and considering starter motor draw you may be down to 8v or lower and the EFI still must function and trigger the injector. 

You need to determine if you are losing fuel, spark or air when it dies. 

Your problem isn't likely to be the ECM - at least you shouldn't jump to that old cliché right off the bat and blame the computer. In the end it might be the case but you have a LOT of homework to prove that before you can confidently call out a bad ECM.

GD

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k, charge light was the belt was loose, fixed that.  and now i can get it to run with the mass air flow sensor unhooked, Ive re gone over all the connections, double checked the timing, checked the injectors to see if they are still firing, seems like it. when the mass air is plugged in the car looses all will to run and dies,  i dont think its dirty as i have burned threw a whole can of mass air flow cleaner on it while it was off of the car

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Unless you can read live data with a Subaru Select Monitor, or you happen to know the conversion from MAF voltage to grams/second, you are left with checking the MAF input voltage, output voltage (at MAF and at ECM), grounds, and of course everything else - like the ignition system. One of the many problems with these old systems is they have basically zero support and that can make troubleshooting difficult. As I have previously mentioned - you need to move to a standalone that can handle your "mods" and also removes the black box barrier to proper troubleshooting. Not to mention deletes expensive and difficult to source components like that MAF. 

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# 1  #3                                #2 is soaking wet and looks like it hasn't fired once.  #1 looks good, #3 looks like it started to fire. #4... wow, just wow

#2   #4

photo_2021-01-26_21-49-28.jpg

Edited by turbodog
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33 minutes ago, Crazyeights said:

What is the compression in all 4 cylinders? Is the valve timing correct? As I recall once you install the inside timing belt you have to turn the engine one full revolution before installing the second belt. A cylinder leakdown test would also give us some useful information.

compression isnt the best, but ironicly the ones with the best are not poping, 150 psi in #2 and 130psi in #4 yeah i did the cam timing,  at least i remembered how to do that,  lol

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What came of the mass air flow sensor “lead” that you had? You haven’t fully ruled this out. 

Also see if you can find a trouble shooting table that references engine runs with MAF disconnected. 

Long shot, but in our 2000 VT Holden commodore V6, it was gutless to drive at one point. Pulled the MAF/pressure sensor (I forget what it was exactly) and it would run ok, not all power was there but you could drive it easily. 

The issue turned out to be the fuel pump dying. Dunno how the sensor disconnect trick changed anything. Car ran awesome after the pump replacement. No random stalling, no stuttering or loss of power issues with load or acceleration. As I said, long shot with it being the fuel pump - could be an electrical issue at a joint that’s got high resistance or an issue with the fuel pump relay. 

Some easy things to check out there anyway. 

Cheers 

Bennie

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6 hours ago, el_freddo said:

What came of the mass air flow sensor “lead” that you had? You haven’t fully ruled this out. 

Also see if you can find a trouble shooting table that references engine runs with MAF disconnected. 

Long shot, but in our 2000 VT Holden commodore V6, it was gutless to drive at one point. Pulled the MAF/pressure sensor (I forget what it was exactly) and it would run ok, not all power was there but you could drive it easily. 

The issue turned out to be the fuel pump dying. Dunno how the sensor disconnect trick changed anything. Car ran awesome after the pump replacement. No random stalling, no stuttering or loss of power issues with load or acceleration. As I said, long shot with it being the fuel pump - could be an electrical issue at a joint that’s got high resistance or an issue with the fuel pump relay. 

Some easy things to check out there anyway. 

Cheers 

Bennie

thanks,  ill look into it some more,  this is frustrating,  ive never came across this kinda problem before

 

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Welcome to the EA82T. And this is why there are none left. They are - compared to the simpler engines like the EA81, and even the EA82 without the turbo - unreliable and troublesome and it takes a concerted effort to fix and maintain them. In my opinion anything fuel injected that is 25+ years old needs a standalone. We use LINK ECU's. 

Maybe you would have more money for a standalone if you didn't spend money on mods that accomplish nothing. Just sayin. 

MegaGarbage works terrible on Japanese applications in general. Doesn't handle most Japanese style triggers and too much timing drift and screwing around with circuits and serial communications. Absolute trash - we remove them constantly due to poor (literally and figuratively) installations when they just can't do what the customer wants.

I think the EA82T is just likely beyond your skill set and patience. The fact that you can't communicate with the factory computer makes them a really tough diagnostic problem. 

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3 hours ago, GeneralDisorder said:

Welcome to the EA82T. And this is why there are none left. They are - compared to the simpler engines like the EA81, and even the EA82 without the turbo - unreliable and troublesome and it takes a concerted effort to fix and maintain them. In my opinion anything fuel injected that is 25+ years old needs a standalone. We use LINK ECU's. 

Maybe you would have more money for a standalone if you didn't spend money on mods that accomplish nothing. Just sayin. 

MegaGarbage works terrible on Japanese applications in general. Doesn't handle most Japanese style triggers and too much timing drift and screwing around with circuits and serial communications. Absolute trash - we remove them constantly due to poor (literally and figuratively) installations when they just can't do what the customer wants.

I think the EA82T is just likely beyond your skill set and patience. The fact that you can't communicate with the factory computer makes them a really tough diagnostic problem. 

GD

yep, i know this engine is trash.  the ecu is trash.  but the money i spent was just in hoses, so... show me a standalone thats under $140

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so, my dislexia strikes again, and i got the fire order wrong, though it didnt solve the whole issue,  it ran great for a minute with the mass air plugged in... then it died again, and wont run with it plugged in.   CEL says code 22 and that says knock control circuit?

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3 hours ago, GeneralDisorder said:

 

Maybe you would have more money for a standalone if you didn't spend money on mods that accomplish nothing. Just sayin. 

 

also, ive undid all the "mods" you said were dumb, if you didnt notice, its reverted to 100% stock as im diagnosing it

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Knock circuit ! Must be the time for it. I run a monitor on mine , Voltage reader in dash from diagnostic wire. Thought baby was a little retarded at times, noticed reader indicating knock - reading 2-4V just off idle. I disconnected whole thing at dizzy ( as you can with Series One ) and just keep revs below 5000 and all fine. With previous FWD set up, different engine , still Series One, I never heard knock even with added boost

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