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Discussion Starter #1
Okay, heres how my morning drive to work goes. I start it up. The colder it is it seems the harder it is to start. After about 30 seconds whether it is still idling or I'm already headed down the road it starts bucking really bad with light pressure on the gas. If I give it more gas it still jerks but the exhaust makes the popping noise. If I floor it it will stop jerking and popping but it is slow to accelerate. Very few times when I have floored it, it would just start bogging down real quick. After about 15 seconds of it jerking really bad it may drive right for a minute and then start jerking but not as bad. And for the rest of the 30 minute drive it may run perfect and it may lightly jerk the whole time. It will start lightly jerking at any time, any rpm, and any gear. When I'm at idle and it is in this "mode" it idles around 650 to my normal 900 rpms and it shakes the whole car. It seems like most of the time if I'm driving and the car is running fine when I go to stop and let it idle for a sec the rpms will drop and it will start lightly jerking again as I go through the gears untill who knows when. It has been doing this for 2.5 years!!! It was really bad when I got it but I replaced the TPS, EGR vacume hose and IAT sensor. I have also just replaced the cap, rotor, plugs, checked ignition module, adjusted timing, checked MAF and cleaned it, checked ECT sensor, replaced thermostat and ECT sensor for dash, replaced pcv valve, looked at all wires and vacume hoses. Checked fuel pressure and it is perfect even when the car is jerking, cleaned IAC valve and tried to adjust it but it was already at the best setting. My oxygen sensors indicate rich and lean on both sides. It can change from running perfect to running like crap at the flick of a switch. When I replaced the spark plugs #8 plug had some oil on it like it was leaking through a valve seal. All others were perfect. Please give me some ideas as to what it could be!
 

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It could be something as easy as timing. Check your timing and see what it reads. Make sure if you adjust it, that you take the little plug thingy out to reset the puter. Its located right next to the distributer. Your timing should be around 12-16*. Or if you have stick, which Im assuming you do, your throw out bearing could be bad causing your clutch to chatter making the car "buck" Hope this helps and good luck
 

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Here's what I'd look at and/or do:
• Check the computer codes. This may lead you right to the problem.
• Replace as many of the under-hood hard (and probably old & brittle) vacuum lines as possible with ordinary rubber vacuum hose. One little vacuum leak can wreak all sorts of havoc, and replacing the old lines is cheap insurance. When you're done, you can use a length of leftover hose as a sort of crude stethoscope to check for leaks at junctions, trees, actuators, etc.
• Observe the engine running at night in a dark place to look for arcing from the plug wires. A light misting with a spray bottle may help you see voltage leaks.
• Clean and test the EGR valve. Use a hand-held vacuum pump to see if the needle moves easily, and that the diaphram isn't leaking.
• Observe the timing mark and see if it's rock-steady, or if it jumps around a bit. If it's a bit jumpy it may be due to a stretched timing chain or perhaps a failing Hall-effect sensor in the distributor.
• Use some electrical connector cleaner spray to clean the pins of the two ten-pin connectors located at the rear of the intake manifold. You might want to adjust the male pins or female sockets to get a tighter fit for better connections. A bit of dielectric grease on the pins couldn't hurt.
• Replace the fuel filter. It's pretty cheap and easy.
• Check the TPS voltage and adjust if necessary. It should be, IMO, between .990 and .996
Good luck, problems like this can be caused by sooooo many interrelated things. I'm sure there are a few more that I didn't think of, but most of these are solutions I've used over the years when I've had similar symptoms.
BTW, have you done compression and leak-down tests?
 

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Discussion Starter #4
I have checked my timing many times and never saw it jump. I did take out the spout connector. I have replaced the clutch with a Motorsport HD unit. I works great with my 4.10s.

Here are my codes:
172, 173, 176, 177- my oxygen sensors indicating I am running rich and lean.
542, 543-fuel pump wire shorted from battery to pcm and from pcm to fuel pump.

I don't think it could be the 02 sensors because of how quick after I start the car it starts messing up and i installed a fuel pressure guage and mounted it on the hood so I could read it while it was bucking and it was perfect. I have done the engine running test and it did not come up with anything. I have not performed a compression test or leakdown test. I don't know anybody that has one and I am too strapped for cash right now to buy one. I am going to try to clean the ten pin connector and check all vacume hoses real good.
 

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ever find out the problem? i have the same one and was wondering.
 
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