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Please help!! Dont understand

  • Thread starter Thread starter blackstallion89
  • Start date Start date Aug 19, 2007

blackstallion89

New Member
Aug 18, 2007
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Aug 19, 2007
#1
  • Aug 19, 2007
  • #1
I have an 89 GT 5.0 Stock bottom end with a B-303 cam. Car has been running excellent until recently when I added a BBK cold air kit with a granatelli mass air meter w/ cold air tune. I also installed a Holley 70 mm throttle body along with a 70 mm egr plate. I installed some yellow top 24 pd injectors and I ordered the granatelli tuned for 24 pd injectors. The intake is a stock 5.0. The problem im having is that the car idles fine and revs excellent as long as your not in gear or when the clutch is pressed. But when you are in gear and on the throttle wide open the car starts hesitating and misses at wide open throttle. The throttle also kind of sticks when you give it gas. And it has no problem in the linkage but its like it kind of hangs and falls slowly. I dont understand what it could be so any advice would be greatly appreciated.

Ive already adjusted the tps setting to the .9 range but havent disconnected the battery would this help?
 

NKau

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Dec 15, 2001
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Jefferson, WI
Aug 19, 2007
#2
  • Aug 19, 2007
  • #2
I guess check and be sure you don't have any vacuum leaks around your throttle body first. Not sure if it applies to the Granatelli units, but some mass air meters like to be 'clocked' a certain way. Loosen the clamps that hold the cold air intake tubing to your MAF, and try rotating the MAF to a different position and see if anything changes.
 
8

86bluecobra

Advanced Member
Dec 20, 2004
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Aug 19, 2007
#3
  • Aug 19, 2007
  • #3
number one would be to check the codes.
 

RYC CUKR

Founding Member
May 19, 2002
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Orlando
Aug 19, 2007
#4
  • Aug 19, 2007
  • #4
Like 86 said pull the codes and see what you have there.

Personally I think that the injectors are way to big for a mostly stock car. 19s are good up to 250-270rwhp. I have also heard lots of guys that have probs with the 24s wanting to run rich even when used in the proper application. Keep in mind this is not from personal experience but rather from hanging around here for the past few years.

If you don't get anything on the codes I would go back to the 19lbs and stock MAF and keep the BBK on and see if that helps with the problem. If it doesn't then pull the BBK and put it back stock and see if the prob goes away. Then add in the 24s and MAF with the stock air box and keep adding stuff until your problem reoccurs. At least then you have an idea of what mod is causing the issues.
 

88mouse

New Member
Apr 18, 2007
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Mooresville nc
Aug 19, 2007
#5
  • Aug 19, 2007
  • #5
Im with RYC the injector are way to big for your set up. Try puting the stock injector and meter back on it. Keep the 24's and meter untill you get some heads and intake.
 

blackstallion89

New Member
Aug 18, 2007
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Aug 19, 2007
#6
  • Aug 19, 2007
  • #6
thanks for the help guys i'll read the codes tommorrow and see whats gong on
 

blackstallion89

New Member
Aug 18, 2007
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0
Aug 20, 2007
#7
  • Aug 20, 2007
  • #7
Codes

These are the codes as follows:

KOEO
35, 85,29, 35,63, 66

I couldnt get the codes for koer with the code reader i have so i may have to do it manually.

Note: The smog stuff was removed before I got the car so it still has the egr plate and the egr sensor is still plugged in but none of the other lines such as the ones on top of the egr plate have not ever been hooked up.

Hope some one can help me using this information before I go through the trouble of starting to take it back apart.

Thanks ahead of time.
 

jrichker

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Aug 20, 2007
#8
  • Aug 20, 2007
  • #8
blackstallion89 said:
These are the codes as follows:

KOEO
35, 85,29, 35,63, 66

I couldnt get the codes for koer with the code reader i have so i may have to do it manually.

Note: The smog stuff was removed before I got the car so it still has the egr plate and the egr sensor is still plugged in but none of the other lines such as the ones on top of the egr plate have not ever been hooked up.

Hope some one can help me using this information before I go through the trouble of starting to take it back apart.

Thanks ahead of time.
Click to expand...

Code 29 - Vehicle Speed Sensor (VSS) is an electronic sender mounted on the speedo pickup gear on the trans. It works the cruse control for both 5 speed and auto trans cars. The VSS is used to tell the computer to speed up the idle as you slow to a stop. This helps keep the engine from stalling when you slow down for a stop sign or stop light.
Check to see if the electrical connector is plugged into it. Clean the connector & contacts with non flammable brake parts cleaner prior to replacing the sensor, as that may fix the problem. The sensor cost is under $30 and it is easy to replace.

Code 35 EVR - EVP sensor signal is/was high – Bad sensor, or possible missing ground for EVR circuit. With the power off, measure the resistance between the black/white wire and battery ground. You should see less than 1 ohm. Check the same black /white wire on the TPS and MAP sensor. More than 1 ohm there and the wire is probably broken in the harness between the engine and the computer. The 10 pin connectors pass the black/white wire back to the computer, and can cause problems.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

See http://fordfuelinjection.com/index.php?p=6 for more wiring help & 10 pin connector diagrams

Code 63 - Throttle Position Sensor (TPS) signal too low TPS . TPS out of adjustment, or 5 V VREF missing, broken wiring or bad connections.

Wire colors & functions:
Orange/white = 5 volt VREF from the computer
Dark Green/lt green = TPS output to computer
Black/white = Signal ground from computer

Always use the Dark Green/lt green & Black/white wires to set the TPS base voltage.

Use the Orange/white & Black white wires to verify the TPS has the correct 5 volts source from the computer.

Setting the TPS: you'll need a good Digital Voltmeter (DVM) to do the job. Set the TPS voltage at .5- 1.1 range. Because of the variables involved with the tolerances of both computer and DVM, I would shoot for somewhere between .6 and 1.0 volts. Unless you have a Fluke or other high grade DVM, the second digit past the decimal point on cheap DVM’s is probably fantasy. Since the computer zeros out the TPS voltage every time it powers up, playing with the settings isn't an effective aid to performance or drivability. The main purpose of checking the TPS is to make sure it isn't way out of range and causing problems.

The Orange/White wire is the VREF 5 volts from the computer. You use the Dark Green/Lt green wire (TPS signal) and the Black/White wire (TPS ground) to set the TPS. Use a pair of safety pins to probe the TPS connector from the rear of the connector. You may find it a little difficult to make a good connection, but keep trying. Put the safety pins in the Dark Green/Lt green wire and Black/White wire. Make sure the ignition switch is in the Run position but the engine isn't running.

Here’s a TPS tip I got from NoGo50

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks.

(copied from MustangMax, Glendale AZ)

A.) Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

B.) When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

C.) Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

D.) The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.

Code 66 MAF below minimum test voltage.
Insufficient or no voltage from MAF. Dirty MAF element, bad MAF, bad MAF wiring, missing power to MAF. Check for missing +12 volts on this circuit. Check the two links for a wiring diagram to help you find the red wire for computer power relay switched +12 volts. Check for 12 volts between the red and black wires on the MAF heater (usually pins A & B). while the connector is plugged into the MAF. This may require the use of a couple of safety pins to probe the MAF connector from the back side of it.

There are three parts in a MAF: the heater, the sensor element and the amplifier. The heater heats the MAF sensor element causing the resistance to increase. The amplifier buffers the MAF output signal and has a resistor that is laser trimmed to provide an output range compatible with the computer's load tables.

The MAF element is secured by 2 screws & has 1 wiring connector. To clean the element, remove it from the MAF housing and spray it down with electronic parts cleaner or non-inflammable brake parts cleaner (same stuff in a bigger can and cheaper too).

The MAF output varies with RPM which causes the airflow to increase or decease. The increase of air across the MAF sensor element causes it to cool, allowing more voltage to pass and telling the computer to increase the fuel flow. A decrease in airflow causes the MAF sensor element to get warmer, decreasing the voltage and reducing the fuel flow. Measure the MAF output at pins C & D on the MAF connector (dark blue/orange and tan/light blue) or at pins 50 & 9 on the computer. Be sure to measure the sensor output by measuring across the pins and not between the pins and ground.

At idle = approximately .6 volt
20 MPH = approximately 1.10 volt
40 MPH = approximately 1.70 volt
60 MPH = approximately 2.10 volt

Check the resistance of the MAF signal wiring. Pin D on the MAF and pin 50 on the computer (dark blue/orange wire) should be less than 2 ohms. Pin C on the MAF and pin 9 on the computer (tan/light blue wire) should be less than 2 ohms.

There should be a minimum of 10K ohms between either pin C or D on the MAF wiring connector and ground. Make your measurement with the MAF disconnected from the wiring harness.


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel pump, alternator, ignition & A/C wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Computer,. actuator & sensor wiring
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Fuse panel layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

Vacuum routing
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

Code 85 - CANP solenoid - The Carbon Canister solenoid is inoperative. Check vacuum lines for leaks and cracks. Check electrical wiring for loose connections, damaged wiring and insulation. Check solenoid valve operation by grounding the gray/yellow wire to the solenoid and blowing through it.
The computer provides the ground for the solenoid. The red wire to the solenoid is always energized any time the ignition switch is in the run position.

Charcoal canister plumbing - one 3/8" tube from the bottom of the upper manifold to the rubber hose. Rubber hose connects to one side of the canister solenoid valve. Other side of the solenoid valve connects to one side of the canister. The other side of the canister connects to a rubber hose that connects to a line that goes all the way back to the gas tank. There is an electrical connector coming from the passenger side injector harness near #1 injector that plugs into the canister solenoid valve. It's purpose is to vent the gas tank. The solenoid valve opens at cruse to provide some extra fuel.

It does not weigh but a pound or so and helps richen up the cruse mixture. It draws no HP & keeps the car from smelling like gasoline in a closed garage. So with all these good things and no bad ones, why not hook it up & use it?


The code 66 is probably what is hurting your performance.
 

blackstallion89

New Member
Aug 18, 2007
16
0
0
Aug 21, 2007
#9
  • Aug 21, 2007
  • #9
Fixed

Thanks for the help the problem was that the mass air sensor plug wasnt getting a good connection. After I fixed it the car smoothed out instantly now the main thing I see in the codes (KOER) is that im getting a code 41 saying im running lean. I have the 24 pound injectors, a 24 mass air, but stock regulator. Would that cause it to say that? Thanks again
 

cenok is family

15 Year Member
Jun 25, 2003
1,409
69
79
Norman, Ok
Aug 21, 2007
#10
  • Aug 21, 2007
  • #10
blackstallion89 said:
Thanks for the help the problem was that the mass air sensor plug wasnt getting a good connection. After I fixed it the car smoothed out instantly now the main thing I see in the codes (KOER) is that im getting a code 41 saying im running lean. I have the 24 pound injectors, a 24 mass air, but stock regulator. Would that cause it to say that? Thanks again
Click to expand...

get an adjustable fuel pressure regulator and take your car to get tuned. lean issue solved.
 
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