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T-bird Tim
02-15-2006, 04:36 PM
I just put a ported supercharger and inlet plenum on my SC and put it in the tune shop for tuning and a chip. The car was running awesome when I first got it back but the last couple of days I have noticed a couple of issues. When I am just cruising along and punch the gas, the boost gauge immediately pegs out and the supercharger is screaming. The problem I'm having is that after this it takes one to two seconds for the transmission to react and gear down to take advantage of all the boost and added power. The tranny is only a year old and I checked the fluid and its full. Is there any adjustment needed on the throttle linkage that would alleviate this. Also when I'm slowing down, especially when turning to enter an on ramp or turn off; I get alot of hesitation when I mash the gas. It does that until I get it straightened out and get going down the road. Anyone have any similar occurances with a highly modified engine after tuning? I'm running 42lb injectors and a 255lph pump, fuel starvation maybe? Any help here would be greatly appreciated.

stocker 89
02-16-2006, 02:34 PM
Do it manuel . Try down shifiting into first before pressing the foot feed . DUH. Then shift up at the proper RPMS. This means red line. Double DUH.....

T-bird Tim
02-16-2006, 02:37 PM
Of course I already tried it that way, DUH. Anyone with any REAL suggestions?

David Neibert
02-16-2006, 03:29 PM
The delay in downshifting is a transmission problem. Assuming it's an AOD about the only thing you can do is to re-adjust the TV cable.

The hesitation is most likely related to the tuning that was done. A good tuner will road test the car to make sure there aren't drivability issues like your describing. What kind of chip/software was used to tune the car and did the person doing the tuning know an SC from a Mustang ?

Highly modded cars can have lots of driveability quirks, but with someone doing the tuning who is familiar with SCs they can usually be corrected in one tuning session.

David

RBH Racing
02-17-2006, 12:05 PM
Check your TPS. they can cause a number of shifting issues. best with an oscilloscope, but a voltmeter will do. Improper adjustment can cause delayed shift, harsh or slow downshifts, etc. etc.

.48V at idle and very near 5.0Volts at wot is going to be your two major checks. diagram looks to show a dark green/light green wire for reference return that you should check there with a good ground(battery -). best thing is to slide a needle down the wire at the connector until it contacts the actual pins inside the connector, and then test from the needle.

Ray

David Neibert
02-17-2006, 03:08 PM
Ray,

I don't understand how the TPS voltage can have any effect on an AOD. It's not electronically controlled...just rpms and TV cable.

David

RBH Racing
02-17-2006, 03:23 PM
The PCM uses input from it to alter shifts and shift schedule. Trust me...


Rough or Mushy 4-2 or 3-1 Shift

ROUGH OR MUSHY 4-2 OR 3-1 SHIFT


Incorrect engine performance.
Incorrectly adjusted Linkage.
Improper application of intermediate friction and one-way clutch.
Dirty valve body or sticking valves.
--------------------------------------------------------------------------
Erratic Shifts

ERRATIC SHIFTS

Improper fluid level.
Poor engine performance.
Binding or sticking throttle linkage.
Valve body bolts improperly torqued.
Valve body dirty or valves sticking.
Sticking governor valve.
Damaged output shaft collector body seal rings.
--------------------------------------------------------------------------

Note the incorrect/poor engine performance, Modifications can show the same symptoms as poor performance. Although not often listed or shown the TPS does affect the trans. It reviews vehicle speed, TPS, and MAF along with throttle valve to control shifts.

007_SuperCoupe
02-17-2006, 04:36 PM
The PCM uses input from it to alter shifts and shift schedule. Trust me...

Only on 94+ SC is this an issue. On '93 and earlier, there is NO PCM control over shift points. The tranny is NOT controlled by computer, but rather by TV cable.

T-bird Tim,
The hesitation could be the result of a vacuum leak. When you got everything back together it was probably sealed up good, but then after a few days (particularly on the IC/IC tube joints) some of those points can work loose just a tad, but enough to cause problems. This could also make it "appear" that your tranny is not engaging fast enough.

If the rpms don't jump a bit on the hesitation, then it is more than likely a tranny issue. If they do, then you've probably got a couple things working against you at this point.

What mods do you have that you consider your SC a "highly modified engine"? We need to get a bit more information from you before we can help you any more. Right now we're just throwing ideas out there that may or may not be in the right direction at all.

David Neibert
02-17-2006, 04:37 PM
The PCM uses input from it to alter shifts and shift schedule. Trust me...


Rough or Mushy 4-2 or 3-1 Shift

ROUGH OR MUSHY 4-2 OR 3-1 SHIFT


Incorrect engine performance.
Incorrectly adjusted Linkage.
Improper application of intermediate friction and one-way clutch.
Dirty valve body or sticking valves.
--------------------------------------------------------------------------
Erratic Shifts

ERRATIC SHIFTS

Improper fluid level.
Poor engine performance.
Binding or sticking throttle linkage.
Valve body bolts improperly torqued.
Valve body dirty or valves sticking.
Sticking governor valve.
Damaged output shaft collector body seal rings.
--------------------------------------------------------------------------

Note the incorrect/poor engine performance, Modifications can show the same symptoms as poor performance. Although not often listed or shown the TPS does affect the trans. It reviews vehicle speed, TPS, and MAF along with throttle valve to control shifts.


Ray,

Trust me !!

The AOD has no electrical connection with the rest of the car except for the speedometer signal, reverse lights and netural safety switch. There are no electronic controls for shift firmness, rpms, converter locking unlocking, shift mapping ect ect... That tranny is as dumb as a bucket of wet hair (that's why I like it).

David

T-bird Tim
02-22-2006, 01:43 PM
Thanks for all the input. I took several peoples advice and finally tried to adjust the throttle cable. Seems sometimes that the most simple things work. It runs great now, no hesitation when I punch it. Now to get rid of that pesky check engine light. As usual I can always come on here and get advice that works. Its good to have the support behind these cars. Once again thanks for all the help!