Car Is Jerking..... Help

Spencer Sikora

New Member
Oct 23, 2016
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Whenever I'm crusing at any speed and I wanna give it some gas(push in the pedal just about half an inch) it starts jerking, its small, but still a problem....its small movements. I NEED HELP
 
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I give up. What model year Mustang are we dealing with?

Regardless of the model year, double check that the fuel rail pressure sensor (FRPS) or fuel regulator intake vacuum reference line is connected and leak free. Inspect the line for presence of raw gas.

Has the alternator been tested for excessive AC ripple? Has the battery been checked? This problem could be caused by a bad alternator diode. Don't cut corners here.

Does disconnecting the EGR valve vacuum line change the symptoms?
 
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I had the same problem as you and was told to go from the least expense to the most expense procedure when trying to fix the problem. It would jerk and hesitate but never throw a check engine light. I changed out the fuel filter first, I am glad I changed it, it looked like the original fuel filter and had black sludge looking stuff coming out the end that connects from the tank side. I cleaned out my air filter (K&N drop in filter) and still no change. I even changed out the spark plugs and checked the wires, still no change. I did some more research and found out for a 2003 MACH1 the COPs should be changed out around 90,000 or 100,000 miles. The current mileage on my car at that time was 135,000 miles. Had my mechanic friend look at my COPs and told me they look like the original that came with the car. I Sucked it up and changed out the COPs with Motorcraft COPs from EBAY. OMG big difference not only was my car miss-firing and jerking but didn't realize how sluggish the performance was ( this is my FIRST Ford Mustang and really had no base line on performance) before I changed out the COPs. It felt like I had a new tune in my engine and all I did was change the COPs. Before I couldn't go up a hill at 60mph in 5th gear without major hesitation and jerking during the rpm climb from WOT position. After the change I could be at 40 mph in 5th gear going up the hill in WOT and no bog, jerking or hesitation only steady smooth rpm climb. Let me know if my situation helps or you already changed everything out I mentioned above and still have the same results.
 
I had the same problem as you and was told to go from the least expense to the most expense procedure when trying to fix the problem. It would jerk and hesitate but never throw a check engine light. I changed out the fuel filter first, I am glad I changed it, it looked like the original fuel filter and had black sludge looking stuff coming out the end that connects from the tank side. I cleaned out my air filter (K&N drop in filter) and still no change. I even changed out the spark plugs and checked the wires, still no change. I did some more research and found out for a 2003 MACH1 the COPs should be changed out around 90,000 or 100,000 miles. The current mileage on my car at that time was 135,000 miles. Had my mechanic friend look at my COPs and told me they look like the original that came with the car. I Sucked it up and changed out the COPs with Motorcraft COPs from EBAY. OMG big difference not only was my car miss-firing and jerking but didn't realize how sluggish the performance was ( this is my FIRST Ford Mustang and really had no base line on performance) before I changed out the COPs. It felt like I had a new tune in my engine and all I did was change the COPs. Before I couldn't go up a hill at 60mph in 5th gear without major hesitation and jerking during the rpm climb from WOT position. After the change I could be at 40 mph in 5th gear going up the hill in WOT and no bog, jerking or hesitation only steady smooth rpm climb. Let me know if my situation helps or you already changed everything out I mentioned above and still have the same results.
Wow, I hope it's not misfiring. We changed the fuel filter and small difference, but still happens but is very small
 
Wow, I hope it's not misfiring. We changed the fuel filter and small difference, but still happens but is very small

How many miles is on the car and have you changed out the COPs yet. If you have high mileage and you never changed out the COPs, you probably need to assume that you need COPs. I spent only 200 on Ebay, but I had to buy the FORD MUSTANG TUNE UP KIT. It came with fuel filter, air filter, sparks plug, COPs, PCV Valve and oil filter all Motorcraft brand name. If you don't need all of that you can buy only the COPs for 400 - 500 and now you see why I bought the kit. That is why I got the box and plan on using all the materials except the air filter since I have K&N drop in air filter. Keep us aware what you do and what you use to fix the problem.
 
Whenever I get on it out of the hole it feels like it cuts off its a 96 gt I have not a clue what it is. it happens when it gets to about 4000 rpm


Please resist the urge to create multiple threads for the same thing. I can tell you right now that these symptoms are all related.

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