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  • 1996 - 2004 SN95 Mustang -General/Talk-

Hesitation under aceleration

  • Thread starter Thread starter Jdove97
  • Start date Start date Sep 12, 2018
J

Jdove97

New Member
Sep 12, 2018
2
0
1
1219 28th street as clevland tn
Sep 12, 2018
#1
  • Sep 12, 2018
  • #1
I have a 97 mustang gt that has a bad hestiton under acceleration. 4.6 car 4.9 scat stroker kit. Underdrive pullys 600 c.f. injectors an a 340lph fuel pump witch i just replaced. New egr valve, egr sylinod , tps, idleair controle valve , new belt tensioners an idler pully, spark plugs, plug wires, coil packs, the injectors are new. Fuel filter is good has a stage 3 clutch an t50 trans. Car idles perfect but when driving hestaties. Through alll the gears. Lost on what next step i should take. Fuel rail pressure is at 50psi
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Sep 14, 2018
#2
  • Sep 14, 2018
  • #2
Hi, Being OBD-2, do you own a decent Scantool to view Sensor outputs while running, or to do a Drive Cycle Data-log?Is It throwing any CEL’s, or does the CEL Flash when you’re under acceleration?
 
J

Jdove97

New Member
Sep 12, 2018
2
0
1
1219 28th street as clevland tn
Sep 14, 2018
#3
  • Sep 14, 2018
  • #3
Yes have a scaner an no its not Not throwing any codes
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Sep 15, 2018
#4
  • Sep 15, 2018
  • #4
It still may have Codes Pending in the CPU despite the fact it’s not yet turned the CEL.on. I have a 96’ & it’s had DTC’s pending, with no CEL...Plug in and Check, nothing to lose-right? Don’t have a Scantool that can do full Diagnostics, Drive Cycles, PID’s (W/explanatio) -Advanced Sell’s ACTRON’s that can do that & more, buy or Rent..
Did this issue just occur one day at startup, or did it start hesitating one day & became a little more prominent each time it was driven? Can you rev it up smoothly while it’s sitting~ does it hesitate only under a physical load? Need to at least establish when you first noticed the hesitation and what was occurring just before or when it was first noticed...
Try cleaning out your MAF Sensor with CRC TB Cleaner, look for cracked Vacuum lines and other leaks (ESP. TB Vac. line in rear) , weak; inconsistent Alternator output(Bring to Advanced Auto & Test) check it’s Connector & all Wires Terminated upon it- verify grounding is solid- on Alternator to Battery Gnd.to Chassis- CPU- Block,.., Abnormal Battery Voltage, Check CTS output, pull 02 Sensor & Clean; reinstall, check Fuel pressure & Flow, DPFE Sensor, Crank Sensor, Check CPU & other Connectors for High Resistance Connections or moisture- clean/reassemble w/Dielectric Grease. That include most things I’ve seen wreak havoc on that Genre’ of 4.6l GT’s, excluding all but one you’d replaced. Vague, if you have more info, it’s easier to help on this end...
If you run a drive cycle with your Scantool, you should be able to log all of every sensor’s operational Data and values - in the playback after the Test.. Good luck!_
 
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