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Ford EFI gurus, need help with O2 problem

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Old 11-20-2018, 05:49 AM
  #26  
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Hmm, if you have an 87 harness/ECU, did you splice in the MAF, or are you running speed density? What code is your ECU?

I hear you on the FiTech, I have a 400 hp setup in my basement. I was holding it for a future project, but this one is really pissing me off.
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Old 11-20-2018, 07:32 AM
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I’m running speed density and the ecu is a DA1.
ive put the car away for winter. Out of sight and out of mind. Lol
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Old 11-20-2018, 08:39 AM
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That explains a lot, speed density is much less forgiving of any changes, and the ECU is not as good for helping diagnose from what I have read. Lots of good info on stangnet.com regarding ecu issues.
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Old 11-24-2018, 12:19 PM
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Updat on my issues. Installed the OEM 19lb injectors with matching OEM MAF. Surprise, it started right up and idles great. Blipped the gas, perfect response. Then got out of the car and realized one of the injectors was leaking and dumping gas everywhere. Looks like the problem is my MAF. Searched and found a 93 Cobra ECU with matching 70mm MAF tuned for 24 lb injectors, snatched it up. Reinstalled the 24s, waiting to get the new MAF and ECU. Hoping this issue will now be behind me.

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Old 11-24-2018, 02:25 PM
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Originally Posted by jrmotorsports55 View Post
Updat on my issues. Installed the OEM 19lb injectors with matching OEM MAF. Surprise, it started right up and useless great. Blipped the flags, perfect response. Then got out of the car and realized one of the injectors was leaking and dumping gas everywhere. Looks like the problem is my MAF. Searched and found a 93 Cobra ECU with matching 70mm MAF tuned for 24 lb injectors, snatched it up. Reinstalled the 24s, waiting to get the new MAF and ECU. Hoping this issue will now be behind me.
Your autospell garbled this up a bit, but it sounds like it runs fine with with stock injectors and MAF? Why not stop there and call it a day? A leaky injector can be remedied pretty easily.
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Old 11-24-2018, 02:37 PM
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Lol, fixed it. Going with 24s, as projected output with my heads/cam/intake is more than 19s can support. Should be in the 330-350 hp range.
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Old 11-25-2018, 12:30 AM
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Wow, that’ll be sweet. Looks like you’re back on track.
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Old 11-25-2018, 08:18 AM
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Yeah, fingers crossed . Should know next weekend once I have the new parts.
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Old 11-26-2018, 09:39 AM
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For some reason, I could never get my "F-cammed", Twisted Wedge headed, GT40 intaked, 24 LB injected, 70mm throttle bodied Mustang to run correctly using all brand new 93 Cobra ECU and MAF meter. It ran MUCH better with a stock 1989 ECU and a 76mm C&L MAF meter (which uses the stock MAF electronics) fitted with the proper sized 24 LB sampling tube. This combo even worked well with 8psi of Paxton boost. This was back before anyone was doing custom tuning and everything was "bolt-on".https://www.americanmuscle.com/cnl-76maf-8693gt.html
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Old 11-26-2018, 10:27 AM
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Ugh, not what I want to hear. Well, already ordered the Cobra parts, i’ll give it a shot. Kinda funny, many say to stay away from C&L. All seems hit or miss. Update to come once parts are in.
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Old 12-01-2018, 01:00 PM
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Wohoo! Very happy guy here. Installed the Cobra ECU and MAF, fired right up and ran smooth. No more stinky exhaust. Let her get good and warm then ran KOER test, no more 41 and 91. I do now have 44 and 94 (thermactor and air diverter), but that is not surprising as I don’t have any of the smog stuff installed. Also pulled code 13, idle low, so i’ll have to bump that up a bit. Very happy at the moment, BIG issue off the list.
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Old 12-01-2018, 02:13 PM
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Frickin amazing.
Code 13 could be a vac leak. If no leaks and base idle reset then probably IAC, but those are cheap. I'm betting resetting the base idle will ****** that one anyways
Congrats.
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Old 12-01-2018, 02:28 PM
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Yeah, the idle just needs to be reset, it is high from my manual adjustment of the base idle when it was running rough.
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