1997 Ford F150. 6cyl, 4.2L 138K. Have CEL on and code reads: "P401 - EGR Flow insufficient". I replaced the EGR valve and checked the ports leading into them and they seem clean. There is one additional component called "EGR feedback sensor" which I really don't want to replace unless I can determine that this is faulty.
View 1 Replies1997 F150. 6Cyl, 4.2L, 139K miles. The truck threw a P401 code(EGR Flow insufficient)and won't pass emmisions here (due by the end of March). So far this is what
I've done : Replaced EGR, replaced DPFE, replaced EVR solenoid, removed throttle body manifold under EGR and cleaned all ports (they weren't even dirty), cleaned and checked all vacumn lines from the DPFE to the main EGR tube from exhaust. Also cleaned the main EGR exhaust tube.
Everything is squeaky clean. All voltages going to the DPFE/EGR are spot on and the whole system seems OK. But the P401 code literally comes on almost immediately (less than 2 miles) after clearing the code (I hooked up my scanner to see how long).
1997 Ford F150. 6 cyl, 4.2L, 138K miles. (Still) keep getting back the P401 code. I've checked (and re-checked) and cleaned all the ports and checked connections on the EGR valve, DPFE sensor and EVR solenoid. Everything seems to be working OK. Have replaced the EGR valve, DPFE sensor and EVR solenoid and (still) after clearing the code and driving ~30 miles, I keep getting the CEL light pop back on and P401 code popping up. Is their anything else to check ??
View 5 RepliesMy '96 4L developed the infamous P0401 insufficient EGR gas flow code 6 months ago. Rough running. Forgot to license it, now the St. Emissions Test was due before I could get new tabs issued. Finally got some warm dry weather to work on it. Started with the electrical measurements per DPFE graph of EGR flow vs electrical output to the PCM.
Showed the DPFE sensor failed, low V output max 2v. The old OEM aluminum body DPFE sensor was still in the old girl after 16 years. Corroded internally and ext., one hose nipple almost corroded off. Eureka. Put in a new Motorcraft plastic body upgrade. Same darn code.
Retested everything from the EGR vacuum valve that feeds the EGR valve to the new DPFE and then the EGR tube from the exhaust pipe. All tested ok electrically and leak wise. No fresh air leaks in the EGR V or EGR tube.
All pointed to restriction in EGR gas flow when PCM demanded it. Ran small stainless steel wire down the upper EGR tube line nipple to the EGR orifice trying to clear carbon build up, still the same P0401. Poured several cups of paint store acetone down each EGR tube hose with engine off and at 2k rpm to emulsify and dissolve the exhaust carbon out. Engine vacuum sucked the acetone up thru the EGR valve also cleaning it internally.
Let set overnight and took out for test drive. Still P0401. Almost ready to drive the green beast to the crusher of death.
Poured more acetone in the EGR and let set for 2 days prepared for the emissions station test failure then repair at emissions cert. shop with a shop waiver for no effective repair. Decided that the EGR tube or EGR valve were leaking fresh air, rusted and corroded. The end nuts on the tube were rusted away. EGR tube NLA from any source.
Went to the emissions test today and passed flying colors. NO P0401, drove all day on business. Got relicensed.
The old girl runs and drives like a dream, she's actually parked and sleeping in the garage tonight all pretty and shiny with a wash and wax job, got a reprieve from the Jaws of Death
I have a 2002 F-150 that is showing a code indicating "EGR insufficient flow". I replaced the EGR valve and cleared the light/code, but the "check engine light" keeps coming back on and code indicates the same problem. What may be causing the light to keep coming on, even after replacing the EGR valve?
View 14 RepliesMy 2001 F-150 came up with this code and I changed the EGR valve cleared the code and it returned 15 miles later. The truck only has 30K miles and the warranty expired 24 May.
View 14 RepliesDreaded insufficient EGR flow. I've read I should clean the EGR ports.
I can't really find where these are? I took the throttle body off.
What I should do with this thing? I also get a hesitation on initial take off.
1999 F150 4.2 V6 ... 160k miles on it. Runs good otherwise.
Has a P0401 code EGR unSufficient flow. Ive read several things that it could be, from a DPFE sensor to the EGR valve it's self our that the port going into the TB could be plugged. Truck drives fine does not have a miss or anything noticeable when driving other than the CEL, trucks a 4.6 with 200k on it. Forgot to mention it sometimes gets a P0455 code but i assumed that is gas cap. or could it be related?
View 7 RepliesI got an 0401 EGR Flow Insufficient last week. I cleared it and it showed up again after a couple of days. I replaced the EGR Valve and the 0401 reappeared. I replaced the DPFE and the code did not reappear. Great!
About a week later, I got an 0402 EGR Flow Excessive. New EGR Valve. New DPFE. The hoses to and from the DPFE to the tube look decent. They don't appear to have any build up inside. Code 0401 or 0402 to the tube?
My first instinct is to replace the EGR valve again, assuming the one AutoZone gave me is stuck open. Is there any servicing I can do to it first? Like maybe soak it in carburetor cleaner? Or spray it with WD-40?
I just bought a 1997 ford f-150 4x4 with 4.6 motor. the check engine light came on. My diagnostic tool reads code 401 (egr insufficient flow). I've replaced on the parts on the egr side of engine. light still on. could it be a leak in the vacuum lines. I don't see any wear.
View 4 RepliesI am preparing to combat the old P0401, Insufficient flow issue. While looking at the steps in Alldatadiy the very first decision essentially forks on "EGR System Module" or "Others".
I am just guessing that, since the choice is there, some engines will have one and some will have the other. But I thought I'd come here and see if I could learn a little more about it.
How can I tell what my truck has? I'm sure there is some difference...
I recently purchased a 2000 Accord coupe v6 with 180k on the clock. I've noticed the gas mileage isn't what it should be. The check engine light was on when I bought it turns out it was a p0401 code. I was told at the dealership insufficient egr flow would cause the car to run rich. So I figured that's what is killing my gas mileage. Well after cleaning the egr port, replacing the egr valve, changing the spark plugs and changing the oil there is no improvement.
View 7 RepliesThe truck in question is a 2004 6.0L Excursion, stock original turbo, no tunes, and EGR cooler delete done 1 year ago. Scanned for codes and none were found except for EGR insufficient flow P0401 code which is due to the EGR cooler delete.
Upon startup (no issues there) the VGT reads 67-70, now once the truck goes to high idle to warm up (1150 or so RPM) the VGT slowing climbs to 85 and stays there. If I blimp the throttle or step on the brake it goes back to 67-70 at normal idle. This has been happening for a few months now on a regular basis. I have checked the MAP, BARO, and EBP readings at KOEO and they are all within 0.6 of each other (14.4-15.0). The EBP tube was checked and cleaned (no buildup present)..
I just got a Check Engine light on yesterday. I went to Autozone and got an OBD-II Trouble Code: P0401, Insufficient EGR Flow Insufficient. The Autozone guy showed me an EGR valve for $164 and said it maybe blocked or something. I also checked with a friend who says that as long as the engine is not overheating it should be okay for driving for now.
So the far the car runs just fine, I haven't experienced any issues out of normal. Does the code mean the value need to be replaced?
EGR insufficient flow. EGR valve was pretty bad looking seemed a bit sticky when opened so I replaced it along with gasket. Reset the computer but check engine light came back on code p0401 again. I know you can test by pinching the yellow striped hose at the throttle body to see if the solenoid is bad. The engine will stumble a bit when you pinch it closed, or so I am told. However when I pinch the hose, nothing happens. I do notice that the car does idle kind of roughly.
View 1 Replies1996 Toyota camry le 4 cylinders has code po401 does it damage engine what will it do. Insufficient exhaust flow...
View 3 RepliesI have a 2000 Ford Ranger 3.0L engine, 2 wheel drive, with automatic transmission. Check engine light came on about 3 months ago. checked with scanner and P0401 EGR flow insufficient came up. cleared it and it came back. truck seems to be running fine. I didn't take autoshop as a kid, so i probably will need a little hand holding on this one.
View 14 RepliesSo my check enginr light has been on for a while saying "po411" "insufficient air flow" but dont know where the vacuum leak is coming from. But today I was working under my car and saw this "hose" that is connected to the air pump looks like it's leaking??
View 3 RepliesI have a 98 Honda Accord, automatic, with a 3.0 VTEC engine with 189,350 miles. It was diagnosed with cod P0401: EGR insufficient flow detected.I was told and apparently in the instructions it states the following to repair/fix the problem:
Unplug the EGR Port in the Intake, remove upper portion of Intake Manifold, drill EGR port, install Sleeve and replace EGR Valve. Instructions also indicated I need a EGR Pipe kit: 06175 P8L-A00 which contains a special tool to drill manifold and install Sleeve: Kit 07ZAO-P8AA000.
Is this a easy job? I'm also confused about needing the special tool (I believe it's a drill bit) and drilling the port. Are either one of these two Kits I mentioned really needed? What do you recommend I use to clean the port? I thought I could just clean the port (hole) and replace the manifold gasket.
The heater on my 2001 ford F150 is not heating. The blower is working, the inlet hose is hot, the outlet hose is cold. Removal of hoses confirms that there is very limited flow through the heater core. I flushed it but got only minimal improvement. However when I back flush (reversing the flow through the core) the flow is great. Here's the question: Can I reverse the flow through the heater core on a permanent basis? It seems this would give the needed flow of hot fluid through the core to allow heating. Is there a problem with doing this?
View 14 RepliesMy 97 E350/460ci occasionally sets trouble code 4011. It clears every time I check it with my code reader. Something about insufficient secondary air injection. The dealer ship couldn't duplicate/diagnose the problem. Maybe something with the air injection solenoids.
Otherwise, it runs fine. I did notice on the passenger side of the engine compartment a large black metal filter looking thingie with about a 3/4" outlet that doesn't have any hose on it or seem to go anywhere else. Once in a while when you start it i hear a sort of soft popping noise for a few seconds that I would associate with the air pump.
Also can't get the ABS light to go away. It's out when you start it but as soon as you get going it comes on. I flushed the fluid and replaced the rear sensor to no avail. Also tried to flush out the front tone wheels and sensors.