AODE cry for help.

Check your universal jopints very carefully. This may account for the noise and perceived shudder. Your loss of power is more likely related to engine performance. When was it last tuned? They do not require a lot of attention but, need someone who has a good idea what they are looking for when they have a problem. You may want to stop at one of the auto parts stores that offer free code retrieval to see if they can read your car and give you the exact fault code if any.

BTW, you aren't doing yourself or the trans any good by power braking. The fact it is smooth when power braking would suggest the shudder you describe is not in the trans. If you do power brake, you must be very careful to limit the duration and not overheat the trans which can happen very quickly this way.

Lugnut

Change your plug wires.

Rob

Thanks for the info, I will go down and change the the spark plug wires out right now. The car has, according to the OD 69,000 on it yep 69,000. The reason the original tranny (cause this one is used) went out is because previos owner's son did standing burnouts regularly and "blew it". Yes the EGR is clogged on the car becuase check engine light is on and the last owner said it was EGR. I have heard many horror stories about replacing it and have put it off. Engine was tuned up about 9,000 miles ago, meaning O2 sensors, filter, plugs etc but no spark plug wires. I will take this one step at a time starting from the cheapest fix: spark plug wires and will be sure to keep you guys up dated.

Once again thanks for the info, it is probably the best I have recieved since this problem occured 6 weeks ago.

DTECH

tra>> I am happy to have found this forum as the info seems to be coming from

While you are doing plug wires, remove the throttle body and clean the EGR ports. That is what plugs on those engines - not the EGR valve. (Different things) The EGR valve rarely gives a problem. The ports and DPFE sensor are a different story. They are also bad about fouling MAF sensor which can usually be cleaned. There are pics on the net on How-To clean. You should also check the vacuum tubes for the PCV whicle tend to plug or rupture and fail. Any/all of these things are minor but can cause major headaches.

Lugnut

This really sounds like an engine performance problem. How old are the spark plug wires? These cars will eat a set of cheap (less than about $75) wires in no time. This will cause a misfire under load. The clicking sounds like "spark knock" commonly caused by plugged EGR passages, another common problem on early 4.6 engines. A dirty MAF sensor can cause a severe drop in performance. Although it will often not cause a misfire, it's easy to clean and costs practically nothing to do. I'm going to go out on a limb and say that you likely have all 3 problems, considering the age of the vehicle. I would suggest a complete tune up (plugs, wires, and filters), clean the MAF sensor, and check the EGR system for proper operation. Don't use ANY form of Bosch spark plugs in this motor, they cause all sorts of driveability concerns in the

4.6 engine. Use Motorcraft copper or platinum spark plugs. Check for oil contamination in the spark plug wells from leaky valve cover seals. Because you seem to see a difference in the symptoms between Neutral and Park, have the TRS (Transmission Range Sensor) tested for proper operation. It is very likely ok but it is another possibility .

I replaced the spark plug wires and the shudder is 100% gone, I never had any idea that spark plug wires under load could give problems. I am so glad I did this I was looking at spending alot of money on a new tranny or parts. The tranny still gives a jerky 2nd gear shift and still won't down shift on a up hill load and the shifting sometimes feels like the tranny is confused, switch back and forth on the top and bottom end of 2nd gear gears and varying speeds. I think the fix as I have read is the Trans Range sensor. But before I do this is will tend to the MAF sensor and EGR passages in TB Thanks for the great info this is the best car forum I have found yet.

lugnut wrote:

As a rule of thumb, a transmission should be given benefit of the dout until you are sure the engine is performing as it should. Even if the trans has a problem, it is damn hard to sort it out and determine the exact problem as long as the engine is not up to par. Since the PCM in your car controls the trans, much if not all of your perceived transmission performance problems may be corrected when you complete engine related maintenance. That said, the MLPS or nuetral switch is commonly found to be the source of erratic shift problems. They are relatively cheap and you can replace it yourself if you have common tools including an

8mm socket or box wrench. Just follow the instructions that come with the new one exactly. It should come with a new harness connector to prevent future corrosion failure which is likely the problem with an old one. Also, to clean your MAF, you will need a torx bit with a hole up the middlw of the tip for the security screws that hold it on. You can buy a set of 1/4" drive cheap at most parts stores as long as you can live with a name other than Snap-on.

Lugnut

I am almost positive that erratic shifting is the MLPS, under slight uphill load it will go 1,2,3, OD in under 24 MPH. I cleaned the MAP sensor... I think. It is the sensor in the air filter box, 2 red wires w a red cap? I want to find out what needs to be cleaned to clean the EGR passages before I go replacing the EGR which I heard is a nightmare. Also just for comparison what would you have to pay for a MLPS where you live, I am in LA and Ford wants $150.00 Auto Zone wants $102.99 I remeber hearing this part being a lot cheaper. And if there is a website that you would recommend for this part, good quality, I would appreciate it if you could let me know.

Thanks for the help DTECH

lugnut wrote:

I believe what you cleaned in the air cleaner is the charge air temp sensor. Tha MAF is in the air tube to the engine fom the air cleaner. You will need a Torx bit for the tamper resistant screw. You can get a whole set for about $8 at Autozone or Advance in 1/4" drive. The MLPS or nuetral safety switch is at Autozone on the net for about $23 or Advance for as little as $34. I would not get the Wells one at Autozone. I have had quality trouble with their products. The replacement will come with a new harness adapter. The switch will work if you do not install it but, it may again get moisture in it causing it to fail again.

Lugnut

That would be a matter of what you are comfortable with. I have used several "aftermarket" switches as well as over-the-counter Ford parts. I have had good success with both and all of the aftermarket switches have had the Ford p/n on them along with an obliterated Ford logo. With automobile manufacturing as it is today with most of the components supplied by vendors all over the world, I have no idea how you distinguish OEM from the others other than the location where you purchase it. I did mention the Wells brand as being unacceptable to me because of my experiennce with that brand. There are other brands like Neihoff and Standard that have been around for 50 years that I know of and provide decent quality parts. If you take your car to a Ford dealer and they replace the MLPS as they did on my truck a few years ago, you may find it is also not necessarily a "Ford" brand. The dealer also eventually corrected some brake problems I was having with Bendix brand pads. Bendix happens to be one of the oldest and most reliable parts suppliers to the oem and aftermarket industry. I can't write off a part just because of a name without some other good reason and neither should anyone else. That said, my experience tells me some things to avoid. If in doubt, I will always default to a known value such as an OEM part until I learn otherwise. My experience on the MLPS is that every one of the originals installed on my Fords at the factory have failed between 50-100k miles - not one of the aftermarket replacement switches has failed other than the Wells products. YMMV!!

Lugnut