newbie needs help!
06-14-2003, 06:48 PM
#1
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Join Date: Jun 2003
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Posts: 14
newbie needs help!
Hola people, name's Amy, from San Antonio, TX...</P>
Did a google search for mustang forums and it brought me here. Hopefully someone with some 5.0L knowledge can help me out. I have a '94 ragtop GT that's been driving really strange lately. Everytime I accelerate, the car jerks, like its not getting enough fuel or something. Anyone had this happen to them, or know what could be causing the car to react like that? I appreciate any replies!<IMG src=smileys/smiley1.gif border="0"></P>
06-14-2003, 09:11 PM
#3
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Join Date: Jun 2003
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newbie needs help!
When I accelerate uphill, or when I'm pressing on the gas to maintain a constant speed, the car jerks. It feels like the car's not getting enough fuel or something...hard to describe. Oh and the idle is kind of unstable. The rpm needlewavers slightly. </P>
I took it to the dealer, and the guy said that my ECU was not responding and that the car was in limp mode. They were gonna charge me $650 for the part and labor, but I decided on just buying a used ECU onlineand replacing it myself. Replaced the ECU today, but I'm sure it wasn't just that part that was causing the jerky movement. Any ideas?</P><edited><editID>n3rdgirl</editID><editDate>37786.8028009259</editDate></edited>
06-15-2003, 04:12 AM
#5
Join Date: Jun 2003
Location: Canada
Posts: 39
newbie needs help!
Hi Girl,</P>
Jerking/bucking/stumbling can be a number of things but I'll take a shot at it. I would say it's spark related, wires, cracked spark plug, etc. Do the night test, with the engine running open the hood and look for spark snap you'll hear/see it if it's there, also look for glowing blue around the wires run your fingers over the spark wires to check for it. found nothing? Second test is the mist bottle during the day open the hood and spray down the spark wires one at a time and listen for any change in engine rpm. Third test say the hell with it and replace the wires, plugs, cap and rotor. Watch out for the belt and that alt cooling fin during these tests. If you have a strong spark then look at the fuel system next change the filter and pick up a fuel pressure gauge $25 and monitor your fuel pressure, if the pressure is surging then the fuel pump is on the way out.</P>
hope this helps, Shane</P>
06-15-2003, 01:29 PM
#6
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Join Date: Jun 2003
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newbie needs help!
wow, thanks for the info, Shane!</P>
The only thing is I just had a complete tune-up about a month ago. plugs, dist. cap, rotor, fuel filter, fuel injection service, etc...then again, I didn't replace the wires so that may have something to do with it.... I'll definitely try those tests. Thanks.<IMG src=smileys/smiley4.gif border="0"></P>
06-17-2003, 05:35 PM
#7
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newbie needs help!
ok, I took it to a mechanic who "specializes" in Fords...and this is what he said...</P>
My spark plugs and wires are all aftermarket (bosch), and he's telling me that because they are not motorcraft, the engine isn't receiving the power correctly. (or something along those lines) Does that sound like a valid reason for the jerky movement?</P>
06-20-2003, 04:36 PM
#10
4th Gear Member
Join Date: Jun 2003
Location: B'ham, WA
Posts: 1,484
newbie needs help!
Yeah. Mind you I didn't put them in, but I had bosch platinum +4 plugs in my '91 5.0, and it ran well. I don't remember what wires were on it.
Even with 25% loss of compression on cyl # 6 it still put over 200hp to the rear tires.
Even with 25% loss of compression on cyl # 6 it still put over 200hp to the rear tires.