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Engine A ton of codes

  • Thread starter Thread starter Andresquintana.mma
  • Start date Start date Aug 2, 2021

Andresquintana.mma

Active Member
Nov 28, 2014
207
21
28
Aug 2, 2021
#1
  • Aug 2, 2021
  • #1
I was trying to get another mustang running and swapping parts back and forth, then got the bright idea to disconnect everything and tape it up to spray the engine bay and put new wire loom (it does look a lot better) but now the car won’t start sometimes and if it does start has very poor throttle response and will die on me. Ran thru the cranks but doesn’t start check list have spark at coil have spark at number 5 I know it said to check number 1 I will do so if needed. It was just in a lot more convenient place, have a fuel pressure gauge on when I put the key on it reads 39. So maybe the injectors aren’t firing? Or I must be missing something I triple checked the distributor and I was able to time it to 14 degrees. Not sure if I missed the compression stroke. Triple checked firing order as well. Can’t think of to much else. Maybe the spark plugs are no good? It sat for a while and is low on gas I’m going to grab some gas now but I ran codes and here they are. I know there’s a lot to fix for sure but it ran great before.

KOEO
63
31
81
82
85
87
84
KOER
98
63
Any help would be greatly appreciated and one problem I have for sure is my fuel pump runs constantly. I can hear it pushing the gas thru the lines to the rail.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,226
17,911
224
Massachusetts
Aug 4, 2021
#2
  • Aug 4, 2021
  • #2
Code 63 is that your TPS is set too low at idle. It should rear between 0.5 and 1.25 volts.


Code 31 is your EGR sensor
Code 81 and 82 are the smog pump solenoids
COde 85 is your charcoal canister
Code 84 is EGR

COde 87 is fuel pump primary circuit failure. The fuel pump lost power while the engine was running. Check fuel pump relay, check inertia switch, wiring to/from inertia switch, red wire going to inertia switch for +12volts. Check the other side of inertia switch for +12 volts.



WHat year is this car? ANd if it's an 86-88 is is mass air swapped?
 

Andresquintana.mma

Active Member
Nov 28, 2014
207
21
28
Aug 4, 2021
#3
  • Aug 4, 2021
  • #3
Mustang5L5 said:
Code 63 is that your TPS is set too low at idle. It should rear between 0.5 and 1.25 volts.


Code 31 is your EGR sensor
Code 81 and 82 are the smog pump solenoids
COde 85 is your charcoal canister
Code 84 is EGR

COde 87 is fuel pump primary circuit failure. The fuel pump lost power while the engine was running. Check fuel pump relay, check inertia switch, wiring to/from inertia switch, red wire going to inertia switch for +12volts. Check the other side of inertia switch for +12 volts.



WHat year is this car? ANd if it's an 86-88 is is mass air swapped?
Click to expand...
I had checked tps and it was like 1.1 or 1.2 not far off adjusted it to .98, I don’t have an egr or smog so that’s good. My charcoal canister broke a while back and never got a new one. I know it vents fumes from the gas tank. Would it cause any problems not being there?

ok I will jump on fuel pump. I need to have that fixed for sure. Thanks for the how to on the fuel pump. When I’m checking the wiring to inertia switch is it just key on?

the car is an 89 4 cylinder conversion with mass air.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,226
17,911
224
Massachusetts
Aug 4, 2021
#4
  • Aug 4, 2021
  • #4
Fuel pump constantly runing is a sign of a ECU failure.

disconnect the ECU and test continuity from pin 40/60 to pin 46. You should have it. If not, the pin 46 trace could be burned. You might also want to inspect the capacitorea

Verify your o2 sensor harness jumper is set correctly for your transmission and ECU (manual or auto are pinned differently)
 

Andresquintana.mma

Active Member
Nov 28, 2014
207
21
28
Aug 4, 2021
#5
  • Aug 4, 2021
  • #5
Mustang5L5 said:
Fuel pump constantly runing is a sign of a ECU failure.

disconnect the ECU and test continuity from pin 40/60 to pin 46. You should have it. If not, the pin 46 trace could be burned. You might also want to inspect the capacitorea

Verify your o2 sensor harness jumper is set correctly for your transmission and ECU (manual or auto are pinned differently)
Click to expand...
I have another fox that I can swap the ecu. I think it’s an a9p and I have a standard transmission in there. I’ll test ecu right now. I will check the continuity on current ECU now.
Is the jumper with the wire that loops around in the same connector?
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
Aug 4, 2021
#6
  • Aug 4, 2021
  • #6
Andresquintana.mma said:
I have another fox that I can swap the ecu. I think it’s an a9p and I have a standard transmission in there. I’ll test ecu right now. I will check the continuity on current ECU now.
Is the jumper with the wire that loops around in the same connector?
Click to expand...
Standard as in manual? A9P is for auto.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,226
17,911
224
Massachusetts
Aug 4, 2021
#7
  • Aug 4, 2021
  • #7
The jumper is on the o2 sensor sensor harness normally under the MaF. You really need to pay attention to how it’s pinned as improperly pinning it will fry an ECU.



usually the issue is mixing and matching harnesses in non-original cars where harnesses are sourced from other cars.

here’s how to repin the harness

Electrical - O2 harness repin

This thread is a HOW-TO for the process of repining the o2 sensor harness to match ECU/Trans, in the event the car is swapped. Please do not ask me what the harness should be repined to. The information is out there in an easy google search. Step one. Remove the o2 sensor harness from...
www.stangnet.com

do not put another ECU in until you verify and check for voltage on pin 46. Constantly running fuel pump is a symptom of a fried ECU.

the o2 harness jumper should match the ECU, and the ECU/o2 should match the actual transmission in the car
 
Reactions: Boostedpimp and General karthief

Andresquintana.mma

Active Member
Nov 28, 2014
207
21
28
Aug 4, 2021
#8
  • Aug 4, 2021
  • #8
Mustang5L5 said:
Fuel pump constantly runing is a sign of a ECU failure.

disconnect the ECU and test continuity from pin 40/60 to pin 46. You should have it. If not, the pin 46 trace could be burned. You might also want to inspect the capacitorea

Verify your o2 sensor harness jumper is set correctly for your transmission and ECU (manual or auto are pinned differently)
Click to expand...
How do I test continuity on the ECU? I pulled it out and put my meter on ohms I believe. It’s like the horseshoe. Then you put positive and negative together I got 1.5 and that’s what it’s supposed to be when you test the ECU. But where do you put the positive and the ground? To each individual pin?
i checked my ECU And it’s actually a D3D which I believe it’s a 5.0 auto computer.
 
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