PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

what the hell is causing this restriction with my tune???

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Old Jun 26, 2007 | 11:10 AM
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Default UPDATE! what the hell is causing this restriction with my tune???

For some reason Im getting a restriction in my upper RPMs and with this restriction, my dyno tuner is not able to lean the motor out at all. My A/f from 4900 starts at 12.9 which is good, but just starts getting richer & richer till we shut down at 6900 which then the A/F is 11.7??

My tuner said he has pretty much "zero" fuel being added up top. but for some reason its stuck at 12.3 at 6500 where I make peak power. Heres my setup.

forged 347 11.25:1 comp.
AFR 205s
G5X4
90/90 setup
new style 85mm MAF with 3 to 5 wire adapter
75mm LID
28.8lb injectors
3" duals with X pipe into borla "S type" mufflers
Kooks 1 3/4 headers
asp U/D pulley

thanks for any help.

Last edited by 30th t/a; Sep 8, 2007 at 10:17 AM.
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Old Jun 26, 2007 | 11:27 AM
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Post up your tune so we can take a look.

If your VE, MAF and PE tables are in line (and tuned) then it has to be an adder table giving you more fuel.
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Old Jun 26, 2007 | 11:53 AM
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Is this with MAF enabled?

Take a look at your IDC. What is it up top?

....also,I know this sounds stupid but has PE Modifier vs RPM table been set?

Last edited by Violatorno1; Jun 26, 2007 at 02:11 PM.
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Old Jun 26, 2007 | 03:31 PM
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Sounds like the Catalytic Over Temperature is still left on.

This comes in around 5k and will drop the A/F of the car to some very low values.

Have him/her level the PE table values to what they are at for 4800 all the way out to 8000 and turn the COT Off.
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Old Jun 26, 2007 | 03:32 PM
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All restrictions can be found 1 of 2 ways.

With the MAF chart the signal and see if it levels off.

Watch the MAP reading. A progressively decreasing MAP reading while at WOT (to something like 85 kPa) indicates an inlet restriction.
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Old Jun 26, 2007 | 03:58 PM
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datalog your "commanded airfuel ratio"

you will have 1 of 2 problems.

Too much airflow coming into the motor, vs what is real.

commanding richer than you want.

Ryan
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Old Jun 27, 2007 | 12:27 AM
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i got 10 bux on you're out of injectors
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Old Jun 27, 2007 | 06:03 AM
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Originally Posted by RedHardSupra
i got 10 bux on you're out of injectors
I'm with you. That's why I asked what IDC was reading.
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Old Jun 27, 2007 | 07:54 AM
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Wouldn't being out of injectors make him go lean?

He is saying that the car is going rich.
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Old Jun 27, 2007 | 08:44 AM
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Originally Posted by NoGo
Wouldn't being out of injectors make him go lean?

He is saying that the car is going rich.

I think their reason is that if the injector goes to max Duty cycle they would go static and stay fully open.

I still think its an adder somewhere or the VE and/or the MAF is out of whack.
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Old Jun 27, 2007 | 11:16 AM
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Disable COT (Cat over temp) , it's in the fuel table .
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Old Jun 27, 2007 | 11:35 AM
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Originally Posted by New Era Performance
Disable COT (Cat over temp) , it's in the fuel table .
first thing that popped into my head, but I doubt a pro tuner would miss that.
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Old Jun 27, 2007 | 11:45 AM
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Originally Posted by Frost
first thing that popped into my head, but I doubt a pro tuner would miss that.
oh yea, cause most pros are so detail oriented
i've seen them miss all tables other than PE and call that tuning, so this is actually a minor thing
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Old Jun 27, 2007 | 12:00 PM
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Like said before, check the map readings to see if kpa drops off. Also check CAT overtemp.

As dumb as this sounds, make sure your throttle blade is opening all the way. When I put my 90/90 setup on the holes in the cam of the throttle body were in different spots than stock and my blade opened only about half way when I had the pedal to the floor. If you have tcs on your car there's an adjustment in the throttle cable. It's a little square that you can open and adjust the length of the cable.
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Old Jun 27, 2007 | 02:05 PM
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Originally Posted by 30th t/a
90/90 setup
new style 85mm MAF with 3 to 5 wire adapter
75mm LID
Hmm, that is interesting.

Post up the log and tune file so we can better advise.
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Old Jun 28, 2007 | 06:36 PM
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COT and or injectors
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Old Jun 28, 2007 | 07:28 PM
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This is funny, up to 17 post with ideas, suggestions and thoughts, but no feed back from the original poster,
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Old Jun 28, 2007 | 07:57 PM
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yeh where is he at?? i have run into MANY cars that the cat over temp hasn't been turned off, and people raise questions from that, wondering why their car is rich. between that and the IDC......
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Old Jun 30, 2007 | 08:38 AM
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Originally Posted by kbracing96
This is funny, up to 17 post with ideas, suggestions and thoughts, but no feed back from the original poster,

he's lurking around. probably lookin' for another dyno.
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Old Jun 30, 2007 | 09:06 PM
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I don't see ant COT, but I do see Catalytic Convertor Protection Enable/Disable under Cat Convertor in EFIlive. Is that what's being referred to?
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