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Topic: Fighting a high idle...HO swap related (Read 5892 times) previous topic - next topic

Fighting a high idle...HO swap related

Reply #60
Quote from: TheFoeYouKnow;388449
You should borrow a 60-pin breakout box and check what your o2's are reading.

Just thought of this......since I had help reassembling everything the o2's may have been installed into the wrong sides...I'm guessing the O2's are side specific, right?What are the wire colors for each side??

Maybe my mom installed them incorrectly.............DOH!!!  ;)
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc crap.  14.05 @ 98mph with launching too low and shifting too high.

Fighting a high idle...HO swap related

Reply #61
Quote from: Dan B.;388459
Just thought of this......since I had help reassembling everything the o2's may have been installed into the wrong sides...I'm guessing the O2's are side specific, right?What are the wire colors for each side??

Maybe my mom installed them incorrectly.............DOH!!!  ;)

Yes the O2's are side specific.
From the 88 EVTM: Right= DG/P wire.  Left= DB/LG wire.

You should figure out why you are seeing 6v on the TPS sense wire. If this is not a false reading by the meter, it is the first thing you have to fix. No error codes should be considered valid.
Check with a different meter.
Check a 1.5 volt flashlight battery and see what the meter reads.
The O/W wire on the EGR position sensor, Map and TPS is the 5v reference voltage from the EEC. Check it to ground, then check it to the SIG RTN pin in the self test connector. Are they the same?

Fighting a high idle...HO swap related

Reply #62
Will check the O2's when I have the car lifted for the puel pump swap.

Checked TPS voltage this AM with the stock ECM in place and using a new volt meter.....it read way low (.5v).  Of course, it was set from the DA9 ECM.  So I reset the TPS to .9v.  Ran a full sweep and it went smooth, maxed out at 4.5v.  Also checked the pigtail ground with a volt meter.  It was grounding through the wires but not through the eyelet against the body so I cleaned that up and reconnected.

Reinstalled the DA9 ECM, TPS read way high and fuel pump ran constantly.  Stuck the stocker back in and TPS was fine and fuel pump cycled properly.

I also found a single orange wire sticking out of a wrapped harness around the rear of the intake in the area of the EGR.  It looked cut off.  Any clues??

I reread the entire thread this AM and still have one or two things to check out but thinking it's an ECM issue since things are reading fine with the stock one.
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc crap.  14.05 @ 98mph with launching too low and shifting too high.

Fighting a high idle...HO swap related

Reply #63
It might be the ecm if it reads fine with the old one, however, if you haven't checked ground on pins 20,40,60 and sigrtn, you don't know if its ungrounded because of a wiring problem, or an internal issue.a wiring problem (like the ecm ground near the battery, check resistance and connection here!) Which could burn up the computer. It can also cause problems with turning the fp relay on and off.

Good luck, but I don't think. There is anything else I can tell you.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Fighting a high idle...HO swap related

Reply #64
How do I check ground on the pins??
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc crap.  14.05 @ 98mph with launching too low and shifting too high.

Fighting a high idle...HO swap related

Reply #65
The orange wire is likely the o2 ground wire which should be on one of the intake bolts. I would say the DA9 PCM is bad or not correct for the wire harness,
Ken Collins, BadShoe Productions
How To Videos specializing in Ford powertrains

Fighting a high idle...HO swap related

Reply #66
I have that orange wire also, and like you, it is connected to nothing. On 88, as far as I can tell from the EVTM, it's not used on 5.0.  It seems a little late to ask, but how high is your idle?  I just found out that while I thought my idle was high, it wasn't, my digital tach was just wrong.  I figure it's because the stock 5.0 had a different firing order, but that's just a wild guess.

 

Fighting a high idle...HO swap related

Reply #67
Quote from: TheFoeYouKnow;388951
......how high is your idle?  I just found out that while I thought my idle was high, it wasn't, my digital tach was just wrong.  I figure it's because the stock 5.0 had a different firing order, but that's just a wild guess.

It's around 1200rpm.  With the IAC unplugged it will settle right at 800 and with the stock computer I can get it right also.  But plug the IAC in with the DA9 and it goes high.  Right now I have several items going on and I'm tired of it.  I need to replace the fuel pump and check the DA9 to see if it is toast or not.  There's a local guy that's a wiring whiz and rates are very reasonable.  I'm going to try a few more things on my own, if nothing is fixed after that; it's going to him.
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc crap.  14.05 @ 98mph with launching too low and shifting too high.

Fighting a high idle...HO swap related

Reply #68
Quote from: Dan B.;388459
Just thought of this......since I had help reassembling everything the o2's may have been installed into the wrong sides...I'm guessing the O2's are side specific, right?What are the wire colors for each side??

Quote
I also found a single orange wire sticking out of a wrapped harness around the rear of the intake in the area of the EGR. It looked cut off. Any clues??

I reread the entire thread this AM and still have one or two things to check out but thinking it's an ECM issue since things are reading fine with the stock one.

Read the following thread concerning your o2 sensor harness and whether or not it's reading the wrong banks.  http://www.foxtbirdcougarforums.com/showthread.php?21560-White-10-pin-connector...

As far as the orange wire, it's been pretty much determined that they are redundant in the Cougar/Tbird wire harness and therefore not needed (or even hooked up from the factory) due to the o2 sensor harness in these cars having the grounds built in.  There were apparently different engine harnesses and HEGO harnesses in the Stangs.

Check the following post for the pictures that were removed from the thread I linked to.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!