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Post SC install, car dies with throttle/very tough steering. Hmm?

  • Thread starter Thread starter 281pony
  • Start date Start date Nov 4, 2010

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 4, 2010
#1
  • Nov 4, 2010
  • #1
i installed a vortech s trim, 42# injectors. nothing more, nothing less engine wise. along the way until today, it had no serpentine belt. i started it a few times, barely revved it and all was fine.

today i put on the remaining pieces for my serpentine belt routing. consist of larger ps pulley, wp pulley, fms a/c delete which moved the ps up. thats it. belt was real tight with tensioner, needs to be as small as possible for clearnace.

car starts and idles as far as i can tell, endlessly. no issues there at idle with it dying. car idles low almost like its got a partial load on it however. like 650 rpm's. when i touch the gas, i get a hiss sound, fuel pressure increases and it drops rpm's. it drops rpm's and will die if i keep my foot on the gas, or it will recover and continue to idle.

we have tried the following to trace it; removed primary belt and sc belt, unplugged maf, solid fuel pressure, removed inlet tube for free flowing air completely around sc, no codes, i think thats it....

anyone got an idea? what could cause it to reject any throttle application like this? the steering is also VERY stiff. pump turns fine by hand, belt is definately tight but i even pulled the tensioner off and no improvment to steering feel. no obstructions or anything near any steering components.

 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 4, 2010
#2
  • Nov 4, 2010
  • #2
sorry if my post is kinda scatter brained. long day at work backed up by long night with car.

car idles normal now with belts off, i think it was just learning on initial start. fuel pressure stays at 36ish during idle. jumps to 40 and would continue if the car didnt fall on its face. remember this is at idle and in gear.

went over all vacuum lines and anything i touched during install. only thing left i can think of is my sct chip took a crap? i just had it started and revved it lightly as i said yesterday.

only thing i can conclude with the tight ass steering is the belt is just too tight. ps pump spins freely by hand with normal effort. still does not explain me having no throttle control.

time for sleep.. im exhausted and im not gonna get anywhere else tonight
 
K

knarf

Member
Apr 24, 2010
36
0
6
nj
Nov 4, 2010
#3
  • Nov 4, 2010
  • #3
I assume you have something to work with the 42's mad chip etc. I actually had similar problems the Sep being too tight gave me lousey assist and made the pump whine this was caused by the 3g I had installed which due the bigger case made the belt just a little too short even though I was able to force it on.
The hissing definitely sounds like a vacation leak. Mycar was udling a little low and icouldn't understand why when i'd turn the idle screw in the rpms would drop. I it wadnt until i found a vac line come off that I solved the prob. When I suspect a vac leak. Ill start the engine and spray starting fluid aroun d till I hear the rpms jump. Obviously you need to be very careful due to the stuff being verey flamable, no exaust spark leaks etc
 
1

1990_GT

New Member
Jun 29, 2009
41
0
0
Marysville Wa.
Nov 4, 2010
#4
  • Nov 4, 2010
  • #4
The reason your steering is stiff is because you put a larger pulley on the pump, when you did that it slowed the rpm of the pump down, now its not going to giving you as much assist. I bet you rev the engine up the steering will be mush softer.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 4, 2010
#5
  • Nov 4, 2010
  • #5
1990_GT said:
The reason your steering is stiff is because you put a larger pulley on the pump, when you did that it slowed the rpm of the pump down, now its not going to giving you as much assist. I bet you rev the engine up the steering will be mush softer.
Click to expand...

oh jesus christ.. i wish i had thought of that haha . ill bet your right.

went through everything, it ended up being the chip and the baseline tune on it. it was so rich that it wouldn't rev, and on the start up it was adjusted so that it would do that much.

it's a little rough to start now, i adjusted FP a bit and ill see how it does. gonna drive it later tonight when traffic is less.
 
8

89drop

New Member
Aug 30, 2009
175
2
0
Nov 4, 2010
#6
  • Nov 4, 2010
  • #6
1990_GT said:
The reason your steering is stiff is because you put a larger pulley on the pump, when you did that it slowed the rpm of the pump down, now its not going to giving you as much assist. I bet you rev the engine up the steering will be mush softer.
Click to expand...

that was exactly my thought as i was reading the post... keep us posted!
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 5, 2010
#7
  • Nov 5, 2010
  • #7
drove it about 15 miles tonight. the steering sucks, i think i'm actually better off with a manual rack. this steering feels tougher then with a manual rack.

so i will either give up my ps luxury, or end up doing the damn a/c dummy pulley. winter is coming and ill figure it out when i can actually drive the car.

now the car is chipless again, it has my bad surging idle back. very rich starts/kinda tough starts. so i'm going to try and get it to putt around as good as possible tomorrow. then hopefully have a good day at the dyno on saturday.
 
1

1990_GT

New Member
Jun 29, 2009
41
0
0
Marysville Wa.
Nov 5, 2010
#8
  • Nov 5, 2010
  • #8
What dyno shop are you going to use?
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 5, 2010
#9
  • Nov 5, 2010
  • #9
hp ranch.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Nov 6, 2010
#10
  • Nov 6, 2010
  • #10
With the big injector and large amount of fuel you are very likely to be fuel washing the cylinders...drive it as little as possible.

Why the larger PS pulley, I have never done that for any car?
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 6, 2010
#11
  • Nov 6, 2010
  • #11
Rick 91GT said:
With the big injector and large amount of fuel you are very likely to be fuel washing the cylinders...drive it as little as possible.

Why the larger PS pulley, I have never done that for any car?
Click to expand...

i have been trying to get it as driveable as possible before i leave for the tune. i only have a trailer if it breaks to save my ass. i will lower the fp a little more before i go. i guess i can try the chip once more with the baseline, he thought maybe it wasn't reading cause i needed to clean the connection.

the larger ps pulley is to help with clearance coming over the wp pulley. i got both a 93 cobra wp pulley and the v6 ps pulley. there is maybe 1/4" clearance now. i hope the damn belt atleast lasts me this trip before it starts to rub itself.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Nov 6, 2010
#12
  • Nov 6, 2010
  • #12
it drove all the way to the dyno, 70 miles each way. used just over 1/8th tank there. did very very well on the dyno, then i got 27 mpg coming home

ill post more info later in my talk thread.
 
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