96eb96
Explorer Addict
- Joined
- October 20, 2004
- Messages
- 3,524
- Reaction score
- 323
- City, State
- Albany, NY
- Year, Model & Trim Level
- 96 EB V6 OHV 4WD
Here is my "unofficial TSB"
This could be for almost any Ford that has an EGR valve, but some may be more prone.
A little known source for EGR leaks is the pintle shaft. The EGR will test out perfectly using standard tests, not set any codes but unmetered air is being drawn underneath the diaphragm.
This problem will actually make the EGR function better, because it will move with no resistance! If you look at an EGR you will see a shaft thru the hole. This shaft passes thru a guide and after 15-20 years wears out and leaks. There are vent holes underneath the EGR for the diaphragm but otherwise this should be closed to atmosphere.
Now, this alone will not set a code, but will give you 10-11 positive trim on both banks. This is the "aging" allowance that is built into OBD II. Now, if you have other leaks in the system the number will be much higher and set a code.
To test;
With a scan tool (forscan, whatever) monitor ltft and stft at idle after a trip. If you are at 10 or above total trim:
Spray brake cleaner or propane into the holes under the EGR. Check rockauto for a pic to see where they are. If you notice a change in idle or stft going negative, this is suspect. Mine would buck and hesitate when i tried this. I blocked off the EGR with a gasket and it went away.
Removing the EGR is not fun. The good part is that all the parts are still available! The tube will likely break unless you are extremely careful and lucky. You can try heating the Egr body, then wax, pb, whatever, but there is a good chance the tube will twist. If you are very patient it may come off and be reused. The tube will be so brittle at this age that any movement may crack it.
You can also break the tube at the exhaust nut and put a 1 1/16 I believe to wrench it out. I suggest heating it with mapp and putting candle wax. The fitting and tube are available (guy on ebay is selling tubes for 25 bucks, looks like many are sold for the ohv. I bought the ford one, it was 45(The part is still in production). The fitting is about $10 at the dealer.
This could be for almost any Ford that has an EGR valve, but some may be more prone.
A little known source for EGR leaks is the pintle shaft. The EGR will test out perfectly using standard tests, not set any codes but unmetered air is being drawn underneath the diaphragm.
This problem will actually make the EGR function better, because it will move with no resistance! If you look at an EGR you will see a shaft thru the hole. This shaft passes thru a guide and after 15-20 years wears out and leaks. There are vent holes underneath the EGR for the diaphragm but otherwise this should be closed to atmosphere.
Now, this alone will not set a code, but will give you 10-11 positive trim on both banks. This is the "aging" allowance that is built into OBD II. Now, if you have other leaks in the system the number will be much higher and set a code.
To test;
With a scan tool (forscan, whatever) monitor ltft and stft at idle after a trip. If you are at 10 or above total trim:
Spray brake cleaner or propane into the holes under the EGR. Check rockauto for a pic to see where they are. If you notice a change in idle or stft going negative, this is suspect. Mine would buck and hesitate when i tried this. I blocked off the EGR with a gasket and it went away.
Removing the EGR is not fun. The good part is that all the parts are still available! The tube will likely break unless you are extremely careful and lucky. You can try heating the Egr body, then wax, pb, whatever, but there is a good chance the tube will twist. If you are very patient it may come off and be reused. The tube will be so brittle at this age that any movement may crack it.
You can also break the tube at the exhaust nut and put a 1 1/16 I believe to wrench it out. I suggest heating it with mapp and putting candle wax. The fitting and tube are available (guy on ebay is selling tubes for 25 bucks, looks like many are sold for the ohv. I bought the ford one, it was 45(The part is still in production). The fitting is about $10 at the dealer.
