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Topic: Bad ECM? (Read 19620 times) previous topic - next topic

Bad ECM?

Reply #75 –
The O2 sensors are needed for adaptive learning and fuel trim. Don't delete them if you can help it. Especially since your car is not stock. It will run poorly with no O2 sensors connected.....
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Bad ECM?

Reply #76 –
^Indeed. I've got a catless BBK x pipe, and the FIRST thing I did when I took it out of the box was to put some used, but tested good O2's in it.


Funny thing is though, in my Mounty, despite the lack of O2 inputs, there's still no CEL. It does work...comes on every time I turn the key to on, with engine off...
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

Bad ECM?

Reply #77 –
Alright. I have a BBK off road H pipe. I got o2s pplugged into the bungs, just not plugged into the harness right now. Soo, I guess I'll throw my original automatic speed density o2 harness back in.
1988 Mercury cougar XR7- 302 bored .030 over, gt40p heads, F303, AlexsParts spring and seal kit, explorer upper and lower intake, 70mm tb, maf conversion, 75mm maf, fenderwell cai, 24 lb injectors, T5 conversion, bbk h pipe, Slp lm, 3.73 rear, 4 wheel disc conversion, 5 lug conversion. :D :D

Bad ECM?

Reply #79 –
I found this link to an excerpt from another O2 discussion on corral. http://forums.corral.net/forums/11151822-post16.html This made me think more along the lines of putting the speed density harness back in because I am using the factory speed density eec harness. And like those diagrams between the 93 stang and 88 cat/bird from Softtouch, pins 43, and 29 are both utilized. So I'm thinking I'll be alright.

So I did go over today, fired her up, adjusted timing to 12 degrees btdc with spout connector out, and then adjusted fuel pressure to about 39 lbs. I shut the car off tightened down the dizzy hold down, plugged spout connector in, hooked up fpr vacuum line, and fired her up again. Computer was holding timing right around 12 degrees. After she warned up, idle came down to about 800 rpm or so. I shut her down. Let sit for 10 minutes or so, fired back up, let her idle a few minutes, then shut down again. I did this 3 or 4 times prolly, to make sure she'd start. then I tried to start and she just cranked. Didn't even try to fire. So I pulled the plug off the coil and layed a screwdriver across the shock tower to hover an inch over the coil terminal. I cranked and it sparked once, then nothing. Just cranking. No spark. I did still have fuel prime and pressure though. So I'm back to the drawing board when I get over there next.

As for the no check engine light, that's because I put the bulb in the spare bulb check engine light spot. So I put the bulb in the right side check engine light slot and now I have the light on all the time.so I'll pull codes again when I get over there next as well.
1988 Mercury cougar XR7- 302 bored .030 over, gt40p heads, F303, AlexsParts spring and seal kit, explorer upper and lower intake, 70mm tb, maf conversion, 75mm maf, fenderwell cai, 24 lb injectors, T5 conversion, bbk h pipe, Slp lm, 3.73 rear, 4 wheel disc conversion, 5 lug conversion. :D :D

Bad ECM?

Reply #80 –
Quote from: FOX-XR7;446342
So I'm back to the drawing board when I get over there next.

.



that repair only in my opinion should not have been so robust because you at this point would have wanted it to fail in the same location again,, ,as in encourage it to if it were going to fail.

the thinnest wire possible was better than the large jump.

I hope the eec broke again in the same spot if the eec is again bad.

this thread sucks for you but interesting either way,, good luck!  keep up the good work to.

Bad ECM?

Reply #81 –
Here's an update for everyone. I went over to the shop today, and I first put the original O2 sensor harness back on. Then I decided I would check codes. I performed a koeo test and got 2 codes. A code 24-ACT low, and code 95-Fuel Pump Circuit Problem. Then the continuous memory had 1 code. Code 11-system ok. I then tried to fire it up. It didn't work, just cranked. I was stumped. I stood there for a minute, got back in the car, this time, I realized I had forgotten to push the clutch in for the past few times since it wouldn't start. So I pushed the clutch to the floor and she fired right up. Haha, silly me. Hopefully all is well. Just need tires, windshield, inspection, and paint. Then I'm good to go. Thanks for the help guys.
1988 Mercury cougar XR7- 302 bored .030 over, gt40p heads, F303, AlexsParts spring and seal kit, explorer upper and lower intake, 70mm tb, maf conversion, 75mm maf, fenderwell cai, 24 lb injectors, T5 conversion, bbk h pipe, Slp lm, 3.73 rear, 4 wheel disc conversion, 5 lug conversion. :D :D

Bad ECM?

Reply #82 –
Quote from: FOX-XR7;446645
Here's an update for everyone. I went over to the shop today, and I first put the original O2 sensor harness back on. Then I decided I would check codes. I performed a koeo test and got 2 codes. A code 24-ACT low, and code 95-Fuel Pump Circuit Problem. Then the continuous memory had 1 code. Code 11-system ok. I then tried to fire it up. It didn't work, just cranked. I was stumped. I stood there for a minute, got back in the car, this time, I realized I had forgotten to push the clutch in for the past few times since it wouldn't start. So I pushed the clutch to the floor and she fired right up. Haha, silly me. Hopefully all is well. Just need tires, windshield, inspection, and paint. Then I'm good to go. Thanks for the help guys.


It cranks without depressing clutch but doesn't start?? Never heard of that one...

It's not supposed to crank unless clutch is pressed...

Bad ECM?

Reply #83 –
Quote from: TurboCoupe50;446666
It cranks without depressing clutch but doesn't start?? Never heard of that one...

It's not supposed to crank unless clutch is pressed...
Sorry. Forgot to mention that when I converted to stick, the used pedal box I got didn't come with the pigtail for the clutch starter switch. So it'll crank with clutch out. I never got a pigtail or wired it up with blade connectors.
1988 Mercury cougar XR7- 302 bored .030 over, gt40p heads, F303, AlexsParts spring and seal kit, explorer upper and lower intake, 70mm tb, maf conversion, 75mm maf, fenderwell cai, 24 lb injectors, T5 conversion, bbk h pipe, Slp lm, 3.73 rear, 4 wheel disc conversion, 5 lug conversion. :D :D

Bad ECM?

Reply #84 –
so,, long story short,, because we are attempting this today.

specifically on the 1988 tbird stock harness..................(which is a unique animal).......

when going to mass air conversion, can we simply follow Eric's mass air write up?  ,, which does not mention any warnings pertaining to 02 sensors or wiring issues?
 

Bad ECM?

Reply #85 –
That is correct. No warnings with O2 harnesses. I can say I am currently using my stock 88 SD o2 harness with a mass air conversion and a mass air computer, and I don't have any o2 codes with engine off. Haven't checked codes with engine running yet. But so far so good.
1988 Mercury cougar XR7- 302 bored .030 over, gt40p heads, F303, AlexsParts spring and seal kit, explorer upper and lower intake, 70mm tb, maf conversion, 75mm maf, fenderwell cai, 24 lb injectors, T5 conversion, bbk h pipe, Slp lm, 3.73 rear, 4 wheel disc conversion, 5 lug conversion. :D :D