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Discussion Starter #41
Ok, car is running back to normal again. Idle is 850rpm instead of 1400-1600rpm now. I am assuming the computer was just needing to relearn itself after cleaning the IACV and driving it for about 20 miles through all kinds of different speed seemed to fix it. Now onto to the dyno tune!!!

Can anyone please tell me what I should gap my Autolite 3924 plugs too before my dyno tune?

Thanks
 

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Ok, car is running back to normal again. Idle is 850rpm instead of 1400-1600rpm now. I am assuming the computer was just needing to relearn itself after cleaning the IACV and driving it for about 20 miles through all kinds of different speed seemed to fix it. Now onto to the dyno tune!!!

Can anyone please tell me what I should gap my Autolite 3924 plugs too before my dyno tune?

Thanks
.044 to .050 would be good.
You could probably go a little bigger since you're running msd ignition.

I wouldn't go any bigger then .054
 

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Discussion Starter #43
Ok, now it seems if its not one thing its another. Coming home from work yesterday sitting at a red light the car starts doing the damn 1400rpm idle again. I shut the car off and turn it back on and it idles at normal 850rpm now and holds.

I get to the mustang shop to talk to the guy who sold me the stang' he was pretty busy of course working on other peoples cars at the end of the so that he could go home. i told him about the idle issue and he told me the car simply needs a tune. He said a tune would fix on all my little problems. I also told him that those were not the stock 19lb injectors that were on the car and he said he knew and he put the 21lb injectors from a 2003 Mustang GT on there with a 73mm MAF and stock 5.0 MAF sensor. So my MAF housing is good at 73mm becasue I have a 70mm throttle body but the sensor is calibrated for 19lb injectors and not 21lb injectors.

I am assuming this is my major issue here on why the car doesnt have the power its supposed to have, esepecailly after changing the BBK air fiilter and new fuel filter. I am have dnyo tune appt for the end of september which will give me enough enough time to save for the aluminum DS and short shifter.
 

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He said a tune would fix on all my little problems.
Keep in mind that a tune won't fix hardware issues. There are any number of issues that a tune most certainly WON'T fix. I would advise to make a serious effort to trouble shoot your current issues before taking it to the shop.
Are you getting any codes?

I also told him that those were not the stock 19lb injectors that were on the car and he said he knew and he put the 21lb injectors from a 2003 Mustang GT on there with a 73mm MAF and stock 5.0 MAF sensor. So my MAF housing is good at 73mm becasue I have a 70mm throttle body but the sensor is calibrated for 19lb injectors and not 21lb injectors.
It isn't the sensor alone that calibrates it. With the C&L meters, you need to match the housing, the sample tube, and the sensor.
You very well could have the correct sample tube for 21's. Have you checked what sample tube you have in the MAF housing?
 

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Discussion Starter #45
The car isn't throwing any codes. Sorry I am new to this but what is a sample tube? When I remove the MAF its just a round block of metal with the little wires hanging on the inside and the connector attached to the top. I measured the round opening of the MAF housing and inside to inside was 73mm. The sensor itself has the "Ford" serial number for the stock 5.0 sensor, the original one that came with that car.
 

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The car isn't throwing any codes. Sorry I am new to this but what is a sample tube? When I remove the MAF its just a round block of metal with the little wires hanging on the inside and the connector attached to the top. I measured the round opening of the MAF housing and inside to inside was 73mm. The sensor itself has the "Ford" serial number for the stock 5.0 sensor, the original one that came with that car.
Attached image - The MAF on left is a C&L, and shows the sample tube. The MAF on the right is stock for fox bodies.

If you have a C&L with no sample tube, then you will want to fix that...
If it has a sample tube, it should be color coded on the flat end, or measure with calipers. You should be able to confirm for your application on C&L's site.
 

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Discussion Starter #47
I will take a look at it and report back. Thanks for the help guys!
 

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Discussion Starter #48
Took the car out for a spin over the weekend and the car shut off 3 times on me while coming to stop within 2 miles. Every time I pushed the clutch in, the RPM's would dip real low then shoot back up. It would only do this when I have the A/C turned on but won't do it with it off.

I checked my IACV and unplugged it while the car was idling and the idle did not change at all, stayed at a steady 850RPM. Does this mean it is bad?

Would the IACV cause my motor to shut off while the A/C was on coming to a stop?

---------- Post added at 07:19 PM ---------- Previous post was at 07:06 PM ----------

The car also has started the hanging high idle for the past 2 weeks. I would come to red light and the RPM would not drop below 1400 RPM so I would have to shut the car off then crank it back up because it was so damn loud and people are looking at me crazy.
 

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Discussion Starter #49
Anyone?
 

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Discussion Starter #50 (Edited)
So after replacing the spark plugs today Autolite 3924 and I gapped them at .049 and changed the oil as it seems my oil keeps getting black every 500 miles.

I wanted to try something out so I let the car stand still at idle while I turned the AC on to rev it a little then the car would die. Without the AC on the car would not die but hold a stead 800 rpm.

So I disconnected the IACV and with the AC on I gave it a few quick revs and the same thing happened again the car died. So I plugged the IACV plug back in with AC still running and gave it a few quick revs the and rpms droped really low about to die then 5 seconds later it did die.

So my solution is the IACV is bad since its not holding a solid idle under engine loads such as the AC.

Any thought?
 

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still no codes?
I would try cleaning the air valve. Brake cleaner works, just get it dried out when done

Did you ever confirm the MAF?
What ecu did you have? Confirm no chip?

Might try setting idle another 50 rpm higher...
 
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