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Discussion Starter #1
Problem has been trying to pick up speed the way the 4.9 intends to. Not racing or nothing but I cant even try to go around a slow driver on the highway without worrying about being rear-ended because my car wont pick up speed when I choose. Its hard to explain but when giving it gas it wants to go but before it even tries it will back down try again back down until i just give in. Reminds me of when I'm below 5 gallons of gas and trying to merge onto the highway.( I gotta a bad tank ) But this problem is with a full tank. Doing my readings on here, some ppl suggest MAF or MAP or COMPLETE TUNE UP and fuel pump and alternator timing ( something like that ). I ran the codes and deleted them. E39 - E75 - E98, drove around for about 10 mins giving it some gas and the codes havent returned. What do you guys think?
 

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White Diamond '03 DHS (with DTS floor shift)
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Start by checking your fuel pressure. Tape the gauge to the windshield and see what the fuel pressure does when you try to accelerate.
 

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1926 Model T street rod, 2000 Jaguar XJ8, 1999 Corvette.
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Good idea. You need to do the basics. Does it downshift? is the fuel filter less than a year old? is the timing to spec? Have a muffler shop verify the cat converter and/or muffler are not plugged up.
 

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1992 Sedan Deville, 1984 Lincoln Town Car
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those codes indicate a VCC problem, VSS problem, ISC problem. Conclusion: your trans needs some tending to. Figure it out soon, it could get worse. check for codes on a regular basis to see if they come back.
 

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Discussion Starter #6 (Edited)
I really dont think it is the transmission causing it but I do know they go out around this time 130xxx...
I dont know about the downshift. I honestly cant remember if I added a new fuel filter when I got it
last summer. Without taking it to the shop what can I do for my transmission?
I should probably replace the fuel filter just in case, right? The cat converter should be
unplugged, the muffler too? I can unplug it myself, right? Also, how do go about checking the fuel
pressure and timing?

I drove it about 20 miles today and the E75 returned.
 

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White Diamond '03 DHS (with DTS floor shift)
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Fuel filter is a possibility if you are bogging down at high fuel demand. Likewise a clogged CAT. You cannot unclog it, though that is not a likely cause. Muffler will not cause this problem. Don't worry about the timing. Unless you messed with the distributor it is OK. You need to get a fuel pressure gauge and attach it to the service port on the fuel rail (looks like a tire valve). Tape the gauge to the windshield and see if the fuel pressure falls off when you get in the throttle. If it does, then the pump is failing.
 

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1992 Sedan Deville, 1984 Lincoln Town Car
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BINGO! The code E75 =intermittent speed sensor (VSS). It's located on the lower RH rear of the transaxle.

This is a permanent magnet that is probably time to replace or maybe just clean it. Metal filings can collect on there and make the trans go crazy.
You can see it by looking under the wheel well. It is bigger than an O2 sensor. It is aluminum and has 2 wires that go into it Purple and Yellow. it has an aluminum casing that is held down to the transmission by two 10mm bolts.

When the VSS drops out the TCC will release, which may seem like the transmission is slipping. If so, that's just another symptom of the VSS dropping out, not a transmission problem.

Find it, and either clean it or replace it because driving with it bad may damage your trans more seriously. It might still be okay if you take care of this problem right away.
 

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Discussion Starter #10
I just figured VSS stands for vehicle speed sensor but the one autozone pictures only shows a hole for one bolt.
 

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Discussion Starter #12 (Edited)
great site but it doesnt list the sensor... Do you think that sensor could be causing the problem, rancher?
Also, will the fuel pressure gauge hose come long enough to reach the windshield?

can you provide the part number for the guage? All i found was one for $130
 

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White Diamond '03 DHS (with DTS floor shift)
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I can't recall where I bought my gauge. A local place called Farm & Fleet as I recall. Check Walmar, Kmart, AZ, Napa. I don't think most come with a long enough hose. I lengthened mine. You can also buy an R12 refrigerant hose to replace the one on the gauge.

Not sure if the sensor will cause your symptoms, but with that code it needs to be replaced anyway.
 

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I just figured VSS stands for vehicle speed sensor but the one autozone pictures only shows a hole for one bolt.
Sorry, it does only have just one bolt on yours. Finally found the picture in my FSM . I would recommend just cleaning it first. Maybe you wouldn't need a whole new one if it solves the problem. It's pretty easy to get at.
 
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