Just going by what Ford says for the 2001. Your right this one does not monitor EGT, i was thinking of Toyota.
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Could this be the EGR valve?
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"EGR Flow rate is not measured directly as part of field diagnostic procedures." In other words you dont check EGR flow as part of any test in the course of trying to find an issue. But, the computer is aware of the flow.
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The Delta Pressure Feedback EGR system is a closed loop EGR control system that uses Delta Pressure
Feedback EGR sensor (DPFE) to measure EGR flow across an orifice in the EGR tube. When the EGR valve is
open, a pressure differential is created across the orifice and measured by the DPFE sensor. This DPFE
measurement is used to control the EGR vacuum regulator (EVR), which provides vacuum to open and modulate
the EGR valve itself.
The DPFE sensor is a ceramic, capacitive-type pressure transducer that monitors the differential pressure across a
metering orifice located in the orifice tube assembly. The differential pressure feedback sensor receives this signal
through two hoses referred to as the downstream pressure hose (REF SIGNAL) and upstream pressure hose (HI
SIGNAL). The HI and REF hose connections are marked on the aluminum DPFE sensor housing for identification
(note that the HI signal uses a larger diameter hose). There are two styles of DPFE sensors. The newer, plastic
housing utilizes a 1.0-volt offset (zero reading) whereas the older, aluminum housing utilizes either a 0.5-volt or
1.0-volt offset. See the ESM EGR section for the 0.5-volt offset transfer function. The slopes for either offset are
identical.
DPFE Sensor Transfer Function
DPFE volts = Vref [( 0.683 * Delta Pressure) + 20 ] / 100
Volts | A/D Counts in PCM | Delta Pressure, Inches H2O
0.0489 10 -27.9
0.76 156 -7.0
1.0 204 0
1.24 254 7.0
2.02 415 30
3.05 624 60
4.07 834 90
4.96 1015 116
Code:
The Delta Pressure Feedback EGR system is a closed loop EGR control system that uses Delta Pressure
Feedback EGR sensor (DPFE) to measure EGR flow across an orifice in the EGR tube. When the EGR valve is
open, a pressure differential is created across the orifice and measured by the DPFE sensor. This DPFE
measurement is used to control the EGR vacuum regulator (EVR), which provides vacuum to open and modulate
the EGR valve itself.
The DPFE sensor is a ceramic, capacitive-type pressure transducer that monitors the differential pressure across a
metering orifice located in the orifice tube assembly. The differential pressure feedback sensor receives this signal
through two hoses referred to as the downstream pressure hose (REF SIGNAL) and upstream pressure hose (HI
SIGNAL). The HI and REF hose connections are marked on the aluminum DPFE sensor housing for identification
(note that the HI signal uses a larger diameter hose). There are two styles of DPFE sensors. The newer, plastic
housing utilizes a 1.0-volt offset (zero reading) whereas the older, aluminum housing utilizes either a 0.5-volt or
1.0-volt offset. See the ESM EGR section for the 0.5-volt offset transfer function. The slopes for either offset are
identical.
DPFE Sensor Transfer Function
DPFE volts = Vref [( 0.683 * Delta Pressure) + 20 ] / 100
Volts | A/D Counts in PCM | Delta Pressure, Inches H2O
0.0489 10 -27.9
0.76 156 -7.0
1.0 204 0
1.24 254 7.0
2.02 415 30
3.05 624 60
4.07 834 90
4.96 1015 116
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Originally Posted By: Trav
I would pull the EGR and check those passages, use a piece of old speedometer cable to clean the crud out, make a few little kinks in it the first couple of inches.
You can put one end on a drill and run it at low speed.
Pulled the EGR valve off last night, and it was clean. There were only a few traces of soft carbon, which I was able to clean up just by spraying some WD-40.
Originally Posted By: punisher
No need to pull the EGR.
Apply vacuum to EGR while at idle and see if the engine stumbles/dies, if it does, EGR valve/passages are OK.
Never have dealt with that calibration code (leaded with no O2 sensor) but check to see if there is an octane adjust plug you can remove. There might be a calibration update/PCM reprogram available as well to address pinging. Sometimes with age you get carbon deposits that cause pinging.
If you can, pull codes just to see if anything is hiding in memory.
Most pinging problems on those (at least with US calibrations) is MAF (which you checked) and the ignition curve (hence the PCM reflash I suggested).
Checking the MAF voltage at idle really doesn't help you diagnose a condition that occurs at anything other than closed throttle. A MAF that is borderline often reads normal-rich at idle, and goes lean as you increase airflow/engine load. In a perfect world you could hook up a data/scanner, select fuel trims and verify trims go lean at cruise/accel, but since you have no O2 sensors, I just do not know how you would diagnose that with any certainty.
I couldn't find my hand vacuum pump to test to EGR, but I took the car to the dealer in February to check for a PCM firmware update. The PCM was already up to date, so I suppose that takes that off the list.
I'm upgrading the MAF to an 80 mm one soon, which does require a tune. Maybe that ought to fix the issue, if the MAF is indeed the culprit. The MAF is also the factory unit, and hasn't been changed.
Originally Posted By: PZR2874
I would CLEAN the EGR first
Then follow up with a SeaFoam treatment
Then check the plugs
That's just me.
The EGR was clean, and I'm a bit nervous about pulling the plugs to be honest, considering this engine is known for spitting out plugs due to the half threads. They've got 50,000 miles on them at the moment, and I usually replace them every 62,500 miles though, so they will be replaced. I'm also replacing the ignition coils with a set of Steeda COPs. Guess I may just have to bit the bullet early and replace them though, instead of putting the old ones back and replacing them again in 12,500 miles.
Originally Posted By: 440Magnum
Does that engine management system configuration use knock sensors?
Ford introduced knock sensors in 2003. Being a 2001, I don't have knock sensors I'm afraid.
Originally Posted By: Jim Spahr
I would definitely try cleaning the EGR valve first before you replace it. Buy an EGR gasket (Fel Pro) and remove and clean the old EGR. Make sure it works while you have it off. Apply vacuum to it /while it is out of the car/ and see if the diaphram opens the pintle and keeps it open while the vacuum is applied. Clean the carbon off the pintle and the passages. Clean the gasket area and the passages on the block. If the EGR tests good, use the new gasket and reinstall it.
Another thing to check is the spark plug wires. They were often a problem on that model Ford engine and were often mistaken for many other problems: transmissions, fuel pump, etc. If you do decide to change the spark plug wires, use only OEM ie Ford replacements, even though they are rather expensive.
I can't find my vacuum pump, but I may try and borrow one off a friend just to check the EGR valve off the vehicle.
Having said that, I haven't got spark plug wires I'm afraid, as the vehicle utilizes a coil on plug ignition system.
Originally Posted By: Trav
Are the EGR ports going to both heads? That's where my mind was wandering, you know one side restricted.
The only cars i ever saw with official cat delete were GM's brought into Germany early/mid 80's era, the problem was they left the O2's in and they fouled quickly.
This leaves me wondering how Ford is controlling the fuel trim or are they?
This leads me to wondering about more deposits on one bank than the other because of it.
I don't really have any answers more like only questions.
No offence intended you always have valid points and quality input as i hope i do as working mechanics we tend to wander into deeper waters.
IMO its a good thing to dissect the problem and the answers to find the correct answer, i welcome it and hopefully learn something every day.
The EGR valve is connected directly to the intake plenum, so it mixes with air coming in from the throttle body and goes to both banks through the intake manifold.
Originally Posted By: eljefino
I wonder how much effort Ford put into your specific cat-delete engine tune. If you have no cat you may not have the back pressure to send enough smoke through the EGR system. And Ford may not really care.
Also with fuel octane there's a "sensitivity" that's the difference between Research and Motor octanes, which is surely different between leaded and unleaded. You could have a new problem or your fuel blender just came up with a lousy batch.
GM made turbocharged Typhoons and Syclones for the Mideast market that were designed to run in open loop on leaded fuel. They just lopped the wires off the o2 sensors in place-- talk about half-baked programming!
Unlike the Typhoons, there are no slots in the exhaust system for oxygen sensors. No idea how Ford has programmed the PCM to compensate for this though.
Originally Posted By: mechtech2
...hot intake air...
This is what I'm leaning towards right now. My intake air temperature reads anywhere between 122-148 (upper left):
I would pull the EGR and check those passages, use a piece of old speedometer cable to clean the crud out, make a few little kinks in it the first couple of inches.
You can put one end on a drill and run it at low speed.
Pulled the EGR valve off last night, and it was clean. There were only a few traces of soft carbon, which I was able to clean up just by spraying some WD-40.
Originally Posted By: punisher
No need to pull the EGR.
Apply vacuum to EGR while at idle and see if the engine stumbles/dies, if it does, EGR valve/passages are OK.
Never have dealt with that calibration code (leaded with no O2 sensor) but check to see if there is an octane adjust plug you can remove. There might be a calibration update/PCM reprogram available as well to address pinging. Sometimes with age you get carbon deposits that cause pinging.
If you can, pull codes just to see if anything is hiding in memory.
Most pinging problems on those (at least with US calibrations) is MAF (which you checked) and the ignition curve (hence the PCM reflash I suggested).
Checking the MAF voltage at idle really doesn't help you diagnose a condition that occurs at anything other than closed throttle. A MAF that is borderline often reads normal-rich at idle, and goes lean as you increase airflow/engine load. In a perfect world you could hook up a data/scanner, select fuel trims and verify trims go lean at cruise/accel, but since you have no O2 sensors, I just do not know how you would diagnose that with any certainty.
I couldn't find my hand vacuum pump to test to EGR, but I took the car to the dealer in February to check for a PCM firmware update. The PCM was already up to date, so I suppose that takes that off the list.
I'm upgrading the MAF to an 80 mm one soon, which does require a tune. Maybe that ought to fix the issue, if the MAF is indeed the culprit. The MAF is also the factory unit, and hasn't been changed.
Originally Posted By: PZR2874
I would CLEAN the EGR first
Then follow up with a SeaFoam treatment
Then check the plugs
That's just me.
The EGR was clean, and I'm a bit nervous about pulling the plugs to be honest, considering this engine is known for spitting out plugs due to the half threads. They've got 50,000 miles on them at the moment, and I usually replace them every 62,500 miles though, so they will be replaced. I'm also replacing the ignition coils with a set of Steeda COPs. Guess I may just have to bit the bullet early and replace them though, instead of putting the old ones back and replacing them again in 12,500 miles.
Originally Posted By: 440Magnum
Does that engine management system configuration use knock sensors?
Ford introduced knock sensors in 2003. Being a 2001, I don't have knock sensors I'm afraid.
Originally Posted By: Jim Spahr
I would definitely try cleaning the EGR valve first before you replace it. Buy an EGR gasket (Fel Pro) and remove and clean the old EGR. Make sure it works while you have it off. Apply vacuum to it /while it is out of the car/ and see if the diaphram opens the pintle and keeps it open while the vacuum is applied. Clean the carbon off the pintle and the passages. Clean the gasket area and the passages on the block. If the EGR tests good, use the new gasket and reinstall it.
Another thing to check is the spark plug wires. They were often a problem on that model Ford engine and were often mistaken for many other problems: transmissions, fuel pump, etc. If you do decide to change the spark plug wires, use only OEM ie Ford replacements, even though they are rather expensive.
I can't find my vacuum pump, but I may try and borrow one off a friend just to check the EGR valve off the vehicle.
Having said that, I haven't got spark plug wires I'm afraid, as the vehicle utilizes a coil on plug ignition system.
Originally Posted By: Trav
Are the EGR ports going to both heads? That's where my mind was wandering, you know one side restricted.
The only cars i ever saw with official cat delete were GM's brought into Germany early/mid 80's era, the problem was they left the O2's in and they fouled quickly.
This leaves me wondering how Ford is controlling the fuel trim or are they?
This leads me to wondering about more deposits on one bank than the other because of it.
I don't really have any answers more like only questions.
No offence intended you always have valid points and quality input as i hope i do as working mechanics we tend to wander into deeper waters.
IMO its a good thing to dissect the problem and the answers to find the correct answer, i welcome it and hopefully learn something every day.
The EGR valve is connected directly to the intake plenum, so it mixes with air coming in from the throttle body and goes to both banks through the intake manifold.
Originally Posted By: eljefino
I wonder how much effort Ford put into your specific cat-delete engine tune. If you have no cat you may not have the back pressure to send enough smoke through the EGR system. And Ford may not really care.
Also with fuel octane there's a "sensitivity" that's the difference between Research and Motor octanes, which is surely different between leaded and unleaded. You could have a new problem or your fuel blender just came up with a lousy batch.
GM made turbocharged Typhoons and Syclones for the Mideast market that were designed to run in open loop on leaded fuel. They just lopped the wires off the o2 sensors in place-- talk about half-baked programming!
Unlike the Typhoons, there are no slots in the exhaust system for oxygen sensors. No idea how Ford has programmed the PCM to compensate for this though.
Originally Posted By: mechtech2
...hot intake air...
This is what I'm leaning towards right now. My intake air temperature reads anywhere between 122-148 (upper left):
Okay i see where i was misunderstanding what they were saying.
Thanks for the information, i seem to remember a few hoses coming of the Fords EGR pipe now i think about it.
Thanks for the information, i seem to remember a few hoses coming of the Fords EGR pipe now i think about it.
134* is nothing after a drive.
You said the EGR was clean, did you check the pipes and hoses instead of just the unit?
You said the EGR was clean, did you check the pipes and hoses instead of just the unit?
Originally Posted By: Trav
Okay i see where i was misunderstanding what they were saying.
Thanks for the information, i seem to remember a few hoses coming of the Fords EGR pipe now i think about it.
No problem, thanks for the input!
Originally Posted By: PZR2874
134* is nothing after a drive.
You said the EGR was clean, did you check the pipes and hoses instead of just the unit?
Yup, it's all clean.
Okay i see where i was misunderstanding what they were saying.
Thanks for the information, i seem to remember a few hoses coming of the Fords EGR pipe now i think about it.
No problem, thanks for the input!
Originally Posted By: PZR2874
134* is nothing after a drive.
You said the EGR was clean, did you check the pipes and hoses instead of just the unit?
Yup, it's all clean.
The EGR system is only one of many possible 'ping' producers.
Keep digging.
Keep digging.
Yes, worn ignition components can foul plugs faster, right? Then, there is always fuel delivery.
Carbon in the combustion chamber; not EGR related symptom?
Carbon in the combustion chamber; not EGR related symptom?
Carbon was all the way from my TB to the chamber in my Speed b4 I deleted the system. It was bad.
That is pretty HOT intake air.
Can you route it to get outside ambient air? From the coolest source that you can get to?
Home fabrication can work really well.
PCV drain piing, clothes dryer ducting, etc. Even drain pipes!
Can you route it to get outside ambient air? From the coolest source that you can get to?
Home fabrication can work really well.
PCV drain piing, clothes dryer ducting, etc. Even drain pipes!
An update on what resolved this issue, something I wouldn't have expected.
Although my car does not have catalytic converters, it has four resonators (2 in each exhaust pipe). There's a honeycomb structure in each resonator. I decided I would have them gutted, removed and welded back up by a good exhaust shop.
The engine's now smoother throughout the rpm range, the detonation has completely disappeared and there's a very slight (positive) change in the exhaust note.
Although my car does not have catalytic converters, it has four resonators (2 in each exhaust pipe). There's a honeycomb structure in each resonator. I decided I would have them gutted, removed and welded back up by a good exhaust shop.
The engine's now smoother throughout the rpm range, the detonation has completely disappeared and there's a very slight (positive) change in the exhaust note.
Good diagnosis. An exhaust restriction can be VERY hard to figure out!
Originally Posted By: SteveSRT8
Good diagnosis. An exhaust restriction can be VERY hard to figure out!
I was talking to a friend of mine in Bahrain, who has a 5-speed '01 Crown Vic. He experienced similar symptoms at ~95,000 km (59,375 mile) mark, and asked if I had heat seeping in from around the center hump.
It sounded right, so he suggested replacing the resonators with new pieces of similar length pipes as the rest of the system. I just had them gutted, removed the honeycomb structure and welded them back together. Not sure if there is a benefit of expanding the gases midway and then compressing them again? Anyhow, with all four removed, it's like driving a different car.
Originally Posted By: yonyon
Were those resonators actually cats before you removed the honeycomb structure?
Not sure. I had the same thing done on a buddy's '97 Suburban after it start rattling. Both cars have leaded fuel capability, so I would imagine these would be "poisoned" if they were cats.
Good diagnosis. An exhaust restriction can be VERY hard to figure out!
I was talking to a friend of mine in Bahrain, who has a 5-speed '01 Crown Vic. He experienced similar symptoms at ~95,000 km (59,375 mile) mark, and asked if I had heat seeping in from around the center hump.
It sounded right, so he suggested replacing the resonators with new pieces of similar length pipes as the rest of the system. I just had them gutted, removed the honeycomb structure and welded them back together. Not sure if there is a benefit of expanding the gases midway and then compressing them again? Anyhow, with all four removed, it's like driving a different car.
Originally Posted By: yonyon
Were those resonators actually cats before you removed the honeycomb structure?
Not sure. I had the same thing done on a buddy's '97 Suburban after it start rattling. Both cars have leaded fuel capability, so I would imagine these would be "poisoned" if they were cats.
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Those sounds like cats bud.
Those WERE cats.
I've never really encountered one of these cars with the cats cut out but on many cars the exhaust backpressure is needed for proper operation of the EGR and something would have to be done to get that backpressure back. Loss of EGR isn't as bad for the engine as excessive exhaust restriction, but it isn't good (at least not without a retune) either. This might be worth looking into.
Funny you mention that actually. I've just order a tune which includes an EGR delete, and the valve will be removed. The opening on the intake plenum and vacuum line will be capped off, along with the tube which runs to the exhaust manifold. I suppose that would take care of that?
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