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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

Poor idle after full intake install

  • Thread starter Thread starter Dark01
  • Start date Start date Mar 6, 2020
D

Dark01

New Member
Mar 6, 2020
2
0
1
San antonio
Mar 6, 2020
#1
  • Mar 6, 2020
  • #1
hi I just finished installing sr performance CAI, sr performance 70 mm plenum/Tb and ford performance intake manifold. I been driving it all day and my problem is at stop lights when it starts to Surge crazy from 750 to 300 rpms. When I accelerate it runs fine. Also the exhaust sounds cammed when parked. Any help is greatly appreciated.
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Mar 7, 2020
#2
  • Mar 7, 2020
  • #2
Dark01 said:
hi I just finished installing sr performance CAI, sr performance 70 mm plenum/Tb and ford performance intake manifold. I been driving it all day and my problem is at stop lights when it starts to Surge crazy from 750 to 300 rpms. When I accelerate it runs fine. Also the exhaust sounds cammed when parked. Any help is greatly appreciated.
Click to expand...
Hi,
Sorry to hear. (3) quick questions..
1) What intake did you install from ford racing?
2) Did you also add an aftermarket MAF, or is that stock?
3) Did you hook up a Scantool and pull any codes? They may exist in the absence of a CEL. Showing an active CEL?
Once it’s verified there are no misrouted or damaged vacuum lines, and no intake leaks exist between the MAF and the TB, all wiring checks out as correctly landed and solid. Sensor adjustment and proper function is completed. Do you own a Scantool?
This is a useful checklist you should run through to catch issues with your idle “hunting”. Note: Tuning is generally performed to reprogram the EEC to work with aftermarket components added. In addition to allowing the new parts added to function correctly, it provides the power gains for best performance.
This is done once all proper component function is verified. The EEC is a learning Computer, but there are limitations to that end.

Troubleshoot IAC idle problems 1996-2004

Back to the basics. Check for blown fuses. Especially fuse F2.2 and F2.8 in the Central Junction Box (CJB 1999-2004 MY). Confirm key on power using a known good ground. 1999-2004 MY fuse panel schedule...
www.stangnet.com
1) Did you purchase a TB with a TPS installed, or replace it with your previous sensor? It must be checked for proper voltage output at idle, and WOT.
2) Verify your MAF sensor is clean and free of contamination by blasting is with CRC MAF cleaner. Pull your MAF sensor as the engine is running, if it stalls(or runs awful) it’s generally ok.
3) Hook a vacuum gauge up and see what the vacuum is at idle.

Once diagnostics are performed, nothing is found abnormal, depending on the intake used, Tuning is generally the next step. Once the EEC codes are posted, you’ve verified no vacuum leaks, wiring issues, etc.per above, a tune to integrate the new components into the EEC will allow for proper engine function, and yield the best throttle response, gains for the new components added.
Good luck!
-John
 
D

Dark01

New Member
Mar 6, 2020
2
0
1
San antonio
Mar 7, 2020
#3
  • Mar 7, 2020
  • #3
08GT500 said:
Hi,
Sorry to hear. (3) quick questions..
1) What intake did you install from ford racing?
2) Did you also add an aftermarket MAF, or is that stock?
3) Did you hook up a Scantool and pull any codes? They may exist in the absence of a CEL. Showing an active CEL?
Once it’s verified there are no misrouted or damaged vacuum lines, and no intake leaks exist between the MAF and the TB, all wiring checks out as correctly landed and solid. Sensor adjustment and proper function is completed. Do you own a Scantool?
This is a useful checklist you should run through to catch issues with your idle “hunting”. Note: Tuning is generally performed to reprogram the EEC to work with aftermarket components added. In addition to allowing the new parts added to function correctly, it provides the power gains for best performance.
This is done once all proper component function is verified. The EEC is a learning Computer, but there are limitations to that end.

Troubleshoot IAC idle problems 1996-2004

Back to the basics. Check for blown fuses. Especially fuse F2.2 and F2.8 in the Central Junction Box (CJB 1999-2004 MY). Confirm key on power using a known good ground. 1999-2004 MY fuse panel schedule...
www.stangnet.com
1) Did you purchase a TB with a TPS installed, or replace it with your previous sensor? It must be checked for proper voltage output at idle, and WOT.
2) Verify your MAF sensor is clean and free of contamination by blasting is with CRC MAF cleaner. Pull your MAF sensor as the engine is running, if it stalls(or runs awful) it’s generally ok.
3) Hook a vacuum gauge up and see what the vacuum is at idle.

Once diagnostics are performed, nothing is found abnormal, depending on the intake used, Tuning is generally the next step. Once the EEC codes are posted, you’ve verified no vacuum leaks, wiring issues, etc.per above, a tune to integrate the new components into the EEC will allow for proper engine function, and yield the best throttle response, gains for the new components added.
Good luck!
-John
Click to expand...

Hi thank you for responding, to answer your questions 1) it was the Ford performance intake manifold from lmr PI intake. 2) i reused the stock maf like the instructions asked for. 3) yes I used my scan tool to check for codes and pulled a air temp sensor high voltage code because the New cold air intake didn’t allow me to put that sensor in so it’s not even being used right now.
My biggest question is if a tune will fix all of my problems because I am 100% sure I put the intake manifold on right and the new plenum because I don’t hear any weird noises when putting my ear up to the engine and listening for vacuum leaks but I could be wrong. I made sure all vacuum lines were okay I also reused the throttle position sensor and kinda just put it on without knowing how to make sure it was accurate. I am also willing to get a vacuum gauge if it’ll tell me whether or not there is a leak. What tuner would you recommend I get? Bama or sct?
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Mar 8, 2020
#4
  • Mar 8, 2020
  • #4
Dark01 said:
Hi thank you for responding, to answer your questions 1) it was the Ford performance intake manifold from lmr PI intake. 2) i reused the stock maf like the instructions asked for. 3) yes I used my scan tool to check for codes and pulled a air temp sensor high voltage code because the New cold air intake didn’t allow me to put that sensor in so it’s not even being used right now.
My biggest question is if a tune will fix all of my problems because I am 100% sure I put the intake manifold on right and the new plenum because I don’t hear any weird noises when putting my ear up to the engine and listening for vacuum leaks but I could be wrong. I made sure all vacuum lines were okay I also reused the throttle position sensor and kinda just put it on without knowing how to make sure it was accurate. I am also willing to get a vacuum gauge if it’ll tell me whether or not there is a leak. What tuner would you recommend I get? Bama or sct?
Click to expand...
Hi,
What I normally do, if adding aftermarket parts to another’s, or my own car that works best & nothing is physically wrong with anything, I’m already preparing a tune while the parts are enroute.
Be sure you recheck the torque on your intake bolts, they have a tendency to settle slightly, make sure they’re to proper torque spec’s
You never want to flash a tune on a car with an active CEL on. When you install a new program, the tuner stores the cars stock VIN-specific factory program within, an error may occur if you try to go back stock at some point. Clear ALL codes before you install a new tune, know if they are something you need to repair.
You want the IAT sensor working, It’s a thermistor the motor uses to accommodate for temp & atm conditions, adjusting fuel tables & timing specific to the temp the air entering the motor is. You’ll need to get a grommet, and drill a hole.
I suggest going to the hardware store, H. Depot & locating a rubber grommet, the same thickness of the intake tube wall, use the same measuring device used to measure it. Sensor in hand so you know the fit it right, Remove the intake tube, drill a small hole in the new CAI about where it was before, in your old piping(measure the old holes diameter to have your grommet ID close,
You don’t want it getting sucked in, make sure it’s the right size grommet where inserting the sensor holds it in tight
Deburr it inside & out with a needle file, or other file-(no chips left, clean) check fit, lube the sensor/grommet with a tiny bit of hand soap, install.the grommet, then, the sensor.
It, alone may cause issues with mixture at different points if not connected.
A quick way to find out if leaks are present
is a small smoke generator, you’ll see the air get pulled in, or, spray a non flammable solvent, brakleen, slowly around all points the intake bolts use a little carb cleaner spray, I don’t suggest using flammable unless you’ve done it before & are familiar with just how little is needed, tiny little bursts with the small tube inserted into the nozzle, and are certain you have no plug wires arcing,
!!!Fire won’t just singe hair, you could go up in flames!!!! NEVER work alone, make sure the other person knows how to use a fire extinguisher and a slightly damp large towel in a bucket of water-eye protection, face shield. Grommet type pics below.
NON flammable brakleen evaporates fast, spray it around intake ports, and other lines, CAI, IF RPM’s suddenly change, you may have found a leak.
Go back to it in a few minutes & try again. It repeat, there may be an issue.
Your TPS has an signal output wire, and voltage in. Key off, pull the connector, put your multimeter on Resistance(Ohms). One lead landed to any engine or chassis area where there’s ground, secure/wedge it there, the other to the pin on the TPS. Cycle your throttle by hand, you’ll see the resistance change, now let it go.
You’ll do the same thing, but this time the meter set for DCVolts. You then push a pin through the. Onnector, or use the meter lead, and key on, engine off. You’re setting it at idle rpm’s (don’t need to touch the throttle) Shoot for around 0.75 VDV (3/4 of 1 DCV). Tighten the sensor, recheck
It’s a potentiometer, like a radio’s volume knob. Once you’ve checked, pull the pin (or lead out). Start the engine, it will make a difference being correct.
Tuning:
Simplest, most cost effective is buying a SCT REV-X Tuner from American Muscle, and BAMA has free tunes for life, as long as you own the car. Any tunes for parts as you add them. You request it, it’s sent to your WIFI, downloads on the tuner. Very easy, tuned are very good, yes, it would take care of your idle hunting, and give you some good throttle response and HP/TQ to boot.
Call AM and tell them you want.a RevX, or the SX4 Tuner (no real difference except layout, same functions) with free tunes for life. Your car is a 2001-GT, correct? Read the article about the tuner, below, you want them to create your tunes, so be sure you get BAMA’s “free tunes for life”, you have to request it. They also sell headsets & Cool air intakes, Combo’s, if you’re planning on gears, anyway. Best bang for your buck, getting 4.10’s, or 3.73’s. Not a huge difference in mileage, but the mechanical advantage of having lower gears really makes the car a different animal!
https://www.americanmuscle.com/x4-custom-tuner-9904gt.html

Grommet to do into CAI for IAT sensor....

Any questions, pls just ask!
Best
-John
 
Last edited: Mar 8, 2020
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