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92 SC4 jerking at high speeds HELP

Old 10-21-08, 03:14 PM
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snsrushing
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Default 92 SC4 jerking at high speeds HELP

I just did a full tune up at 169k, ( True Flow air filter, plugs, wires, PCV, coils, dist caps, rad. flush fill, serp. belt) because my SC was running like crap all the time, the last owners neglected it ( a-holes). Well I was getting on the freeway and I got on it a little and I noticed a jerking sensation. I leveled off at 70 and it was fine. I got back on it and took it up to 80 and noticed it jerking off and on. It seems like when I accelerate at high speeds it jerks. At normal driving speeds its fine, it seems like once it gets into 60+ mph territory it gets funny. What do you guys think? What can I do to eliminate some possibilities?
Old 10-21-08, 04:08 PM
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breakb
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might need a new MAF. it was doing that to mine at the lower speeds but when i was full on gasing it. replaced the MAF and it went away. still trying to figure another problem out, but a new MAF can't hurt. u can get one off ebay like $100 or if u find it on here cheaper.

i have a 92 sc4 as well.

Peace out
Old 10-21-08, 11:48 PM
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retrospexo
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you shouldn't be jerking at high speeds, that's dangerous. just pull over and keep your JP tissue box close by.

[sorry i couldn't resist ...I just saw the thread title briefly and, well... you know ]

But yeah, truth be told, I think it has to do with your air/fuel situation. If your MAF isn't the solution check your ignition coils.
Old 10-23-08, 12:41 PM
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breakb
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ok so i tired something else on my SC, there's a thread around about tweaking the TPS. tweaked it again yesterday and the jerking on the freeway almost went away. i have to try tweak um a bit more.

Peace out
Old 10-23-08, 01:55 PM
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snsrushing
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I think one of my cam sensor wires might be the problem. I was out messing with it and I noticed that it was resting on the belt I just had replaced. It had some frayed wires sticking out so I'm wondering if it might have been grounding out some? I'm going to take it out after traffic dies down
Old 10-26-08, 07:40 AM
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snsrushing
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Well it wasnt the cam sensor wire, I think it might be the fuel pump. Under normal driving conditions its fine but when you get on the gas like to pass it starts jerking. The MAF looked ok so I"m assuming the TPS should be in similar shape. I'll repost once I get it fixed
Old 10-26-08, 05:37 PM
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probably not the fuel pump... why do you say the TPS should be ok??? put a voltmeter on it and check it...
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