Car Wont Run With Tps

Christian Cornwell

Active Member
Aug 31, 2016
86
20
28
Upstate NY
So I recently swapped a 5.0 into my formerly v6 car. The motor came out of a 89 and it is all setup running on a computer out of a 95 GT. When I first got the car together I put on the throttle body that the guy gave me when I bought the motor which is presumably a 89 and through a few problems I ended up running the car for a little while without a IAC or a TPS. Now I know it isn't the best idea to do this but the computer has base values for all of these things and with my wideband I could make sure that the car wasn't running lean and trust me is was not running lean!! 5mpg at best and the wideband was always reading somewhere near 10.0 (the car didn't get driven much with that kind of gas mileage). Now that I have a quaterhorse with binary editor and eec analyzer I decided that it was time to go through and fix those things that I had just bandaided to get the car running since they were limiting the computer from determining load and letting the car add in more timing at cruising (atleast the TPS was). So the other day I went through and put a TPS on the car from a 89 GT that I bought at Autozone and the IAC from my v6.I calibrated the TPS and went to start the car and there was a bad sound coming from the IAC so I went through and had a new one of those for a 95 Gt ordered in. Tonight I put that on the car and went to start it and all the car will do is start and rev up to about 4k rpm then stall out on its own. I assumed that some other problem had just come up and checked fuel and spark and both were good so I disconnected the wires for the TPS. Because I'm using the fox throttle body on a sn95 I had to go through and wire the harness to the TPS since the connectors are different. After I disconnected the TPS the car started up and ran perfectly. I assumed that it must just be because of the computer learning that the throttle was always at the same position from the TPS missing so I reflashed the ECU to stock and tried it and no difference.

Really not sure what is going on with this one. I cant think of anything else that might be causing it. The TPS is new and the IAC is new. I verified that the TPS is reading correctly through binary editor and it reads that its at .99ish when nothing is pressing the throttle and it gradually climbs as I press the throttle so I don't suspect it being bad.

As always any help would be greatly appreciated as I am totally stumped this time and don't know what to try next other than a different throttle body and I don't really want to do that as I spent quite a bit of time making brackets and modifying my sn throttle cable to work with the fox throttle body.
 
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Christian Cornwell

Active Member
Aug 31, 2016
86
20
28
Upstate NY
After more thinking the only thing that I can come up with is that maybe the set screw is out of wack somehow making the computer upset. Can anyone take and count how many turns it takes to get the screw all the way in so I can get mine close. I tried it with my other mustang I just bought but it's a 95 and has a 95 throttle body where the car im having problems with has the throttle body from a 89.

I think tonight I might take the throttle body off my 95 with all the sensors and everything and try putting it on my 94 to see if that works. I know there's nothing wrong with that because my 95 is bone stock and runs perfect.
 

Christian Cornwell

Active Member
Aug 31, 2016
86
20
28
Upstate NY
So I just went through and tried what I mentioned above of putting the throttle body off of my 95 on and i ran into a problem. When i went to put the throttle body onto the car none of the bolts would line up. I know i read about using a fox style throttle body on the sn95 cars and i don't remember seeing anything about having to switch intakes. Maybe something is different with mine.

Here's a pic of the intake setup on the car maybe someone knows what year car its off and maybe that is where some of my problems are stemming from. I guess ill try to keep an eye out for a sn95 intake and throttle body and maybe that'll make some difference.

And yes i know that's the wrong intake plaque
upload_2017-10-5_17-37-3.png
 

Christian Cornwell

Active Member
Aug 31, 2016
86
20
28
Upstate NY
When I bought the motor the guy gave me the intake and said the 90° elbow was so it could be used on a sn but I haven't seen any others like it. I fabbed the blower up there when I built all the brackets just because it was the easiest spot for it
 

RioRed95Cobra

Active Member
Apr 7, 2017
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I kinda just went through all this, but the stuff was all sn95.. however.. I had to clock my s trim head unit quite a bit.. You may have to take the head unit off, take out the alan screws, and CAREFULLY rotate the unit so the outlet rotates towards the pass. side.. I don't know where yours is already set, but I had to move mine literally like almost 4 or 5 inches, they slide quite a bit.
 

RioRed95Cobra

Active Member
Apr 7, 2017
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20170313_210826.jpg
20170423_201111.jpg
Here is a shot of mine for reference.. (minus strut tower brace bc I was painting it lol)

Look how the vortech sat prior to me clocking the head unit

PS those are REAL 1968 ish Shelby covers.. and for sale. My 1.7 rr's were tapping the inside of the baffle (old style, different location) ever so slightly and I didn't wanna mangle real authentic pieces. So they sit in my closet.. Maybe someone could use em?
 
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Christian Cornwell

Active Member
Aug 31, 2016
86
20
28
Upstate NY
20170313_210826.jpg
20170423_201111.jpg
Here is a shot of mine for reference.. (minus strut tower brace bc I was painting it lol)

Look how the vortech sat prior to me clocking the head unit

PS those are REAL 1968 ish Shelby covers.. and for sale. My 1.7 rr's were tapping the inside of the baffle (old style, different location) ever so slightly and I didn't wanna mangle real authentic pieces. So they sit in my closet.. Maybe someone could use em?
Maybe I'm misunderstanding you but what would clocking the supercharger do to make a difference with the car not running right with the TPS?
 

Christian Cornwell

Active Member
Aug 31, 2016
86
20
28
Upstate NY
I did go out the other night and pick up a trick flow track burner intake for a good deal with a matching 70mm throttle body. I figure maybe a throttle body with a known good working IAC and TPS would make a difference.

That seems to be how it works though. Go to buy a throttle body off Craigslist and come home with an intake and a lighter wallet...