weird throttle or gas flow problem

[bluidvl]

when i step on the gas it kinda flutters a bit in all gears i have all new injectors,thinking fuel pump but not sure please help.it does not do it at wot,just at low speeds.anyone ever have this problem.

 

[88Stang331]

Try checking the TPS before you do anything drastic. Also if its not doing it at idle and is fine at WOT i would assume its not the fuel pump.

 

[RaceDvr50]

I agree, not a fuel problem. You might also check your timing, might not be advanced enough to come off idle nice. Also what's your setup like? I've seen engines with too much induction on top of stock heads stumble a bit. They catch a big breath of air and the heads cause a bottleneck. They usually run ok through mid and top end.

 

[bluidvl]

i have a stock mass air,65mm tb,headers,high flow cats,h pipe

 

[RaceDvr50]

Ok I think I'll rule out overinduction

 

[bluidvl]

this sucks cause i just got car back from shop what a nightmare that was hade to take car .needless to say the shop sucked and i was turned on to it by local speed shop dont know what they did but it didn't do it before it went there.

 

[RaceDvr50]

What were they supposed to be doing? This might help with the diagnostic

 

[bluidvl]

went from 75mm tb to 65 when i did that it started to idle funny tried to adjust tps but could not get it right.after 2 months yes 2 months in shop and several.things don like egr delete.new injectors,new distributor,i started thinking mass air well turns out resistor was bad. that was a 75mm for 19lb injectors.they replaced with new stock ford mass air.that was the last thing they checked after i said something to them .needless to say i got ripped off!!!!!!!!!!!!!!!!!!!!!!!!!

 

[RaceDvr50]

When you say you couldn't get the TPS right I don't quite follow you, you set it by voltage. Are you saying that the voltage wouldn't stabilize while it sat at closed throttle? If so the TPS is bad or is there some other way that you are trying to set it?

 

[bluidvl]

right idle is better now still stumbles a little but not to bad.put on underdrive pulleys and have idle issues now have to put on alt next

 

[jrichker]

Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.