Mustang Evolution Forum banner

Crap throttle response

2580 Views 55 Replies 11 Participants Last post by  BloodRedStang
I've noticed over the last couple weeks my throttle response is getting slightly worse, there's now a definate delay from putting the pedal down and the engine actually waking up...

Its got a stack racing CAI, just replaced the plugs a couple weeks ago.

Here's some symptoms I've noticed, I don't know how many of these may be connected.

Whining from around fuel door (pretty sure the pumps going)
Slight fuel smell after shutoff
Crap throttle response
Sometimes takes cranking it 20-30 seconds to get it to fire
Sometimes very noticeable vibration at idle unless I rev the engine, kind of feels like a miss.

None of this has really had any affect on the performance, mash the pedal and it'll get up and go.
1 - 20 of 56 Posts
Clogged fuel filter....swap it and see how well that 140 hp gets up and goes :D

If that $10 fix doesnt help id say time to swap the pump.
I was thinking that as well, figured id get some input before I started throwing parts at it.
And it actually feels pretty ballsy for just a 140hp lol

It won't be 140 for long though, turbo 4.2 splitport in the works :D trying to keep it dependable til the new engine and rear end are ready to be dropped in
Youd make more power on a turbod singleport from what the average is online. We hear these type of builds all the time so hope you stick with it. Keep us up to date.
Yea everyone wants to do it but hardly anyone keeps commited
really? I've heard talks of P/P single ports being better for boost but no real figures..
I, by all means, intend to go through with this build. ive found a junkyard by me that'll sell me the entire 4.2 from a 97 f150 for 225, if i go single port ill just buy a shortblock from them.
A buddy of mine has a holset turbo (60mm t4 I believe) he'll sell me for $50, if I go single turbo, I'll probably use that, if I go with twins, they'll be td05 turbos from dsm's.
does anyone know if they're are any known issues or downfalls with the 95 single port heads? I know the 95 3.8 blocks are crap..
That sounds like my old mustang.. I replaced fuel filter. Spark plugs injectors fuel pump and could never figured out why it felt so weak..
It doesn't feel weak though, thats whats weird about it. it hasn't lost any power, theres just a definate delay from hitting the pedal to the engine actually revving. like, if i hit the pedal hard real quick and lift my foot off, i can have my foot off the pedal before the motor actually revs...thats how crap the response is lol

let me rephrase that, it doesnt feel weaker than it actually is being a pretty much stock v6 lol
New plugs? What brand? Fords are picky when it comes to plugs.
It doesn't feel weak though, thats whats weird about it. it hasn't lost any power, theres just a definate delay from hitting the pedal to the engine actually revving. like, if i hit the pedal hard real quick and lift my foot off, i can have my foot off the pedal before the motor actually revs...thats how crap the response is lol

let me rephrase that, it doesnt feel weaker than it actually is being a pretty much stock v6 lol
Well it felt like lazy. I would step on the gas and it would take like 5 seconds to move
audioAl said:
New plugs? What brand? Fords are picky when it comes to plugs.
+1. Indeed very picky.
+1. Indeed very picky.
Yep, best plugs are the motorcraft copper plugs. Buying any of the fancy plugs does no good for us.....I know ive tried.
Plugs are motorcraft coppers lol
Replaced the fuel filter just now, and...wow! Lol the crap that came out of that thing.. I wanna say that that filter had been in there all 180xxx miles of life the cars got.

Throttle response is still kinda ehh, didn't drive it enough to see if the whining and fuel smell was still there, I'm going to go get some gas and drive her around here in a little bit.

I'm going to pull all the plugs tomorrow probably and regap them because I don't think we gapped them to the proper spec when we put them in.

But, so far, no bad vibration at idle, no sounds like a miss :D
good to know the filter has helped so far...it's always a worthwhile replacement
Indeed, thanks for the suggestion.. I tend to be kinda pessimistic with my stang (might be from what happened to my first stang, but that's another story lol) and assume the worst lol.
for the gas smell if it's still there check the fuel filler neck grommet at the tank...you would be surprised how many i order for customers for sn95s
Aha, didn't think to check that. The smell was definately coming from the rear end.
Smell seems to be gone, the whining is definately still there. Had the car checked at advance and its a 95 obd2 (I can use tuners :D) and the alternator is about to go.. its charging at 13.3-5 volts I guess.
So, the alternator may be the cause for some of the weird stuff I've had going on inside the car like on the dash and stuff..

But she's running a hell of a lot better.
Oh, found out I misread the box when I replaced my thermo and I put a 190 degree thermo in.. bout a 160 degree so that's next.

---------- Post added at 02:40 PM ---------- Previous post was at 02:36 PM ----------

Oh, side note, thought this was kinda weird..
Drove the car last night and it was about 50-55 degrees, throttle response was kinda sloppy..no biggy

Started her up today in 18 degree weather and it was great.. touch the pedal and the motors right there.. as it warmed up both outside and the engine itself, it started playing the same tricks.. I don't get it.
a 190 thermostat is normal for our car's isnt it? I replaced mine with a 180 and it runs nice and cool
1 - 20 of 56 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top