Welp! One more Saturday project coming up. OBD2 showed EGR valve insufficient flow. Will test it with vacuum today, but I suspect it's plugged up. It has a 1996 date on it.... I can already see that it will involve removing plenty of other parts to get to it, or a socket wrench with 5 elbows. Plus a gallon of penetrating oil.
I can see trouble with both ends of the exhaust connecting pipe. At the EGR, it's impossible to get a large wrench on the nut without removing a lot of other parts.
I thought about taking it loose at the exhaust manifold, but those nuts look pretty well rusted. The top nut has slashed on the nut, so I assume this is a reverse thread. Why would they use reverse thread when it connects at another nut with regular threads?
Ford may have a better idea, but it doesn't have anything to do with servicing Aerostars...
Not looking forward to skinning my knuckles breaking the old nuts and bolts loose.
I had a stuck EGR valve on my 1995 t-bird 4.6 v8. that year ford shoehorned the EGR between the intake manifold elbow at the rear of the engine and the firewall. damn near impossible to get off the car. No way i could find to get a wrench on the tube from the EGR to the exhaust system so i gave up, squirted some light oil in the EGR vacuum port, attached my hand vac pump to the same port and worked the EGR valve up and down for a good half hour.. and now it seems to work okay. Don't know why. what a stupid place to put the EGR valve, but in 1996 Ford switched to the plastic intake and move EGR and elbow to another location, much easier to get to, but now those plastic intakes are known to fail and leave a nasty mess all under the hood.
insufficient flow. Will test it with vacuum today, but I suspect it's plugged up. It has a 1996 date on it.... I can already see that it will involve removing plenty of other parts to get to it, or a socket wrench with 5 elbows. Plus a gallon of penetrating oil.
This one's on the right sided near the rear (looking from the front of the car). I cranked disconnected and plugged the vacuum line to the EGR and ran a vacuum hose from the EGR out and cranked the engine. Then sucked on the vacuum hose and the engine started to die. This is not a
100% sure test that the exhaust ports are clean, but it does show the valve is opening. I didn't have a vacuum gauge at that time. Will warm the engine that time, and will check the vacuum operation when hot.
Good video for diagnosing problems with a vacuum gauge:
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I'm trying to eliminate the possibiliy of a head gasket leak.
"A head gasket leak can be seen by a regular swing or float between 5 and 19 inHg. Worn piston rings show themselves by a steady low reading"
insufficient flow. Will test it with vacuum today, but I suspect it's plugged up. It has a 1996 date on it.... I can already see that it will involve removing plenty of other parts to get to it, or a socket wrench with 5 elbows. Plus a gallon of penetrating oil.
This one's on the right sided near the rear (looking from the front of the car). I cranked disconnected and plugged the vacuum line to the EGR and ran a vacuum hose from the EGR out and cranked the engine. Then sucked on the vacuum hose and the engine started to die. This is not a
100% sure test that the exhaust ports are clean, but it does show the valve is opening. I didn't have a vacuum gauge at that time. Will warm the engine that time, and will check the vacuum operation when hot.
Good video for diagnosing problems with a vacuum gauge:
formatting link
I'm trying to eliminate the possibiliy of a head gasket leak.
"A head gasket leak can be seen by a regular swing or float between 5 and 19 inHg. Worn piston rings show themselves by a steady low reading"
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Moving right along....
Head gasket was OK. New spark plugs and cleaning & crimping loose spark plug wires to make solid contact fixed rough running.
The lesson I learned (again) is it's not always what the guy at the parts counter thinks it is. And check connections & vacuum lines first.
EGR insufficient exhaust flow error code was a bad DPFE Sensor. Big lesson I learned was not to assume it's the valve. Valve itself is easy to check out by applying vacuum to the port. If you can hear the valve open and close, that means the valve is working. If the vacuum holds that means the diaphragm is likely OK. The only thing you can't check is if the valve opening is blocked. Check the other parts first before pulling out the valve - it really is in the worst possible place to get at.
Check the solenoid last. It's in the back of the engine and you have to remove the computer and floor panel to check the operation & vacuum connections.
This was the best TS procedure for me... only start with the DPFE, and check the others later if needed.
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Highly recommend watching this first. The guys explains how each part of the EGR system works. Not boring.
"Snuffy "Hub Cap" McKinney" wrote in message news: snipped-for-privacy@earthlink.com...
If you had listed the code, someone here (myself included) probably could have told you that. The DPFE was a common problem on my '02 Escape, and from the now-defunct Escape Central, a fairly common problem with most early models. I used to carry a spare in the luggage compartment. It was about 3 minutes to change one out and reset the code (I also have my scanner with me in the car, even my new one now).
I don't know if you've bought a new one or not yet, but my advice is to stay away from the Standard brand and stick with a Ford brand replacement.
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