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I have a 93 F-250 with the 351W, E4OD. My CE light will come on briefly on occassion, so I pulled my codes this morning. This is what I got:
636 - Transmission Fluid Temperature (TFT) not at expected value
328 - EGR valve position sensor below closed limit
Relevant information re: the transmission - I checked the fluid last weekend (hot, idling in park), and it was down off the stick. It took about 2 qts to bring it back up between the two holes on the dipstick (might be a tiny bit above the top hole). Also, this truck has the radiator from a 460 (could it be cooling the trans too much?), as the previous owner had it set up to handle a camper shell and boat, but never really ended up using them.
As for the EGR code, I can't really think of any relevant information that sheds any light on that.
Test your egr valve position sensor to see what kind of voltage output it has, to see if it is in the correct range or if it is malfunctioning. I would also check the EGR valve vacuum regulator, the EVR. It could mean that the EGR is not getting signal to open, either due to a bad evr or bad vacuum lines. It could also indicate that the egr valve is stuck closed. Give these things a check and see what you come up with. The transmission fluid temperature could be due to the low fluid level. Reset the codes and see if that one reappears.
Pulling the negative cable will clear the codes, but you can also reset the codes by pulling the jumper wire while it is blinking codes. That way the computer doesn't have to relearn all its operating parameters and you will not have to reset the radio memory.
Thanks for the pointer on resetting the codes. Reagarding the testing of the EGR system, is there a detailed procedure you can point me to? Would a Haynes or Chilton cover this?
Resetting the codes seems to have cleared the transmission error. Hopefully that was just related to the low fluid level.
OK, picked up a Haynes and (sort of) did the tests it suggests. The voltage and resistance tests were fine, but I don't have a way to do the vacuum tests. Can this be done with a hand pump? Is this a spendy item? After resetting the codes and driving for a while, I am still getting the 328 and am also getting a 327, "EGR valve pressure transducer/position sensor below minimum voltage".
Also, I noticed some Sea Foam at Napa today when I was getting the manual, so I picked up a couple of cans. When adding it via the brake booster line, I noticed some moisture leaking out of the joint where the exhaust manifold meets the exhaust pipe. I suspect I have found the exhaust leak I was previously unable to locate. Is this something I could fix myself (i.e. no welding needed), or is it better left to an exhaust shop?
You can hook up direct manifold vacuum to the egr valve to see if it will open. It's not very precise, but it will give you an idea whether or not the valve is opening, or if the position sensor might be giving a false reading. You can take off the EVP and move it manually to see if it is ok. I'm not sure about how to fix the exhaust leak, maybe someone else can help you out with that.
Thanks for the help with the EGR issues. I'll have to find some time to delve into this further.
I've spent the past couple of hours researching the exhaust leak. It appears that a stock vehicle does not have a gasket at this joint. However, there is talk of people using gaskets. I cannot, however, seem to locate such a gasket at any online store. Can anyone shed some light on this for me? Would my local parts house stock a suitable gasket? Do I want to use some type of form a gasket product? Any help here would be greatly appreciated.
i purchased these from the j c whitney online. they work great better then the 580.00 quoted for the new y pipe
Clamp-a-stud for Most American Cars & Trucks with Heat Riser Each 47ZX0113W $14.95
Clamp-a-stud for Most American Cars & Trucks without Heat Riser Each 47ZX0112Y $14.95
Looks pretty slick. I'm assuming your studs were broken? Mine did not appear to be broken. It looks like it's just not forming a good seal. Were your studs broken? When you used the Clamp-a-stud, did you use any sort of gasket or RTV?
I guess I'll start dousing the bolts in PB Blaster tonight, then try to either torque it tighter or take it apart in a few days. Any advice is appreciated.
OK, I tried applying direct manifold vacuum to the EGR and get no noticeable response. The sensor is off the top, so I can see down into the EGR valve where the spring is located. I do not see any movement or hear any difference in the engine when I apply the vacuum.
Shoud I try cleaning the EGR? Is it definitely defective, or perhaps just stuck? Any recommendations for how to clean?