N/A motor ran on T Ecu, now no start on N/A Ecu

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fngearhead
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N/A motor ran on T Ecu, now no start on N/A Ecu

Post by fngearhead »

So, I swapped the N/A ecu back into my N/A swapped Turbo wagon. I flipped the cam and crank wires to match the N/A setup. Car ran on the Turbo ecu, not great, but it would start and drive. Now, it just spins over and won't start. I don't hear the fuel pump running when the key is first switched on. No fuel smell under the hood either. Any idea where to start looking? Maybe this ECU is junk?
1989 Cherokee-lifted, locked and beat up
1991 Legacy L 5MT AWD with EJ20G swap SOLD... and rolled :(
1993 Turbo Wagon resurrected with '95 WRX guts
Jessekrs123
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Re: N/A motor ran on T Ecu, now no start on N/A Ecu

Post by Jessekrs123 »

Check your fuel pump relay. It's the green one way up under the driver's side dash.
2015 Subaru BRZ
1993 Subaru Legacy Sedan 5 Speed FWD Green (EG33 swap in progress)
1984 Subaru BRAT Tan
fngearhead
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Re: N/A motor ran on T Ecu, now no start on N/A Ecu

Post by fngearhead »

So, I determined the fuel pump wasn't running on the N/A ECU I had. Pumped fine on the turbo ECU. Apparently, a bad ecu then. I got another ecu from a used parts place. Car fired right up but seemed to have a significant miss at idle. As it warmed up idle smoothed out and seems perfect. Try to rev it while in park and it stumbles, misses and backfires. Can't get over 2000 revs. Two things concern me: AUTECS MAF talking to JECS ECU (no CEL), and I gave it a few revs immediately after first startup. Wondering if I screwed the learning curve, so I pulled the ecu fuse for the night and will try again tomorrow.
1989 Cherokee-lifted, locked and beat up
1991 Legacy L 5MT AWD with EJ20G swap SOLD... and rolled :(
1993 Turbo Wagon resurrected with '95 WRX guts
Legacy777
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Re: N/A motor ran on T Ecu, now no start on N/A Ecu

Post by Legacy777 »

Is the MAF the correct MAF for the ECU you're using?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
fngearhead
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Re: N/A motor ran on T Ecu, now no start on N/A Ecu

Post by fngearhead »

Currently running AUTECS MAF and AUTECS ECU. Car seems happier, but still won't rev over 2000. We got a TPS code from the latest ECU, so swapped another TPS in, but no change. I guess its time to start tracing wires and see if there's a break somewhere. Yesterday, TPS code would go away while giving it a bit of throttle and come back at idle. Junkyard parts are plentiful and cheap around here, but its time to stop tossing parts at it.
1989 Cherokee-lifted, locked and beat up
1991 Legacy L 5MT AWD with EJ20G swap SOLD... and rolled :(
1993 Turbo Wagon resurrected with '95 WRX guts
fngearhead
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Re: N/A motor ran on T Ecu, now no start on N/A Ecu

Post by fngearhead »

The car is running on its 3rd N/A ecu. The one that came with it had a dead fuel pump relay control port. Still getting code 31 after tinkering with the wiring on both ends of the TPS system. Also noticed I have nothing in pin B48 16. Its listed as non-turbo atmospheric pressure sensor in a couple of pinouts that I'm referencing. The bottom of B48 connector has obviously been opened before. The fold out lock is a bit boogered. Car currently idles perfectly, but won't rev beyond 1500-2000 without popping and backfiring.
1989 Cherokee-lifted, locked and beat up
1991 Legacy L 5MT AWD with EJ20G swap SOLD... and rolled :(
1993 Turbo Wagon resurrected with '95 WRX guts
Legacy777
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Re: N/A motor ran on T Ecu, now no start on N/A Ecu

Post by Legacy777 »

What is an autoecs MAF? The JECS based non-turbo ECU's require a JECS MAF sensor. If you're not running one, you need to be.

The atmospheric pressure sensor on the non-turbo ECU's is internal to the ECU. You will not see any connection on that pin.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
fngearhead
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Posts: 221
Joined: Tue Nov 09, 2004 9:29 pm
Location: Dillon, CO
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Re: N/A motor ran on T Ecu, now no start on N/A Ecu

Post by fngearhead »

MAF has an AUTECS label on it. ECU is AUTECS as well. I have a JECS MAF and ECU too, but got same results. I'm going to peak under my dash and match wiring on the wagon to mine. Someone has had the TPS related ecu connector open several times on the wagon. That's the only code I'm getting now and makes sense with perfect idle and horrible higher revs.
1989 Cherokee-lifted, locked and beat up
1991 Legacy L 5MT AWD with EJ20G swap SOLD... and rolled :(
1993 Turbo Wagon resurrected with '95 WRX guts
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