Rick's Free Auto Repair Advice

Posts Tagged: P0401

Air injection reaction pump – Taurus Sable.

Fix Air injection reaction pump – Taurus Sable P1414, P1413, P0401, P0402, air injection reaction pump, AIR, Ford Taurus, Mercury Sable. The P1414, P1413, P0401, P0402 code relate to the air injection reaction pump (AIR). The purpose of this pump is to inject air directly into the exhaust manifold to complete the combustion process. At cold startup, the computer commands a rich mixture. The extra air from the AIR pump oxidizes the extra hydrocarbons and carbon monoxide in the exhaust during this rich mixture period. The AIR pump is active … Read More

P0401 P0402 Ford Escape

Fix code P0401 P0402 Ford Escape Owners report repeat P0401 and P0402 codes from the differential pressure feedback EGR sensor (DPFE). If you’ve already checked out my DPFE article here, then head right to the muffler. There’s a small drain at the bottom of the muffler to drain off any condensation that accumulates during a cold start. Shops are reporting that the drain can clog and that moisture can damage the DPFE. Open the drain hole and then drill it one size larger. Next, start the vehicle and run it … Read More

P0401 EGR Code Dodge Caravan, Plymouth Voyager, Town and Country

Fix code P0401 EGR Code on Dodge Caravan, Plymouth Voyager, Town and Country 3.3L and 3.8L Shops are reporting consistent P0401 EGR Codes on 1996-2001 Chrysler minivans. These EGR valves are vacuum operated and the valve operation is measured by a pressure transducer. To check the EGR, start the engine and apply vacuum to the EGR valve. The valve should open, allowing exhaust to flow into the intake manifold. That should make the engine run rough or stall completely. If it does that, then the EGR valve itself is working. … Read More

P0401 Ford Vehicles

Fix code P0401 Ford Vehicles If you haven’t’ already done so, read the full explanation of the DPFE system posted here. This is a very common code of Ford vehicles and can drive people absolutely crazy. Don’t get sucked into throwing parts at this problem. It’s really a fairly simple system. The computer wants to know if the EGR valve is recirculating the amount of exhaust gas that it instructed it to. In order to check that, the DPFE checks for a pressure change above and below a port. It … Read More

P0401

Fix code P0401 Insufficient EGR Flow If you have a P0401 Insufficient EGR Flow trouble code, read this to understand what it means EGR stands for Exhaust Gas Recirculation. At high combustion temperatures, the Nitrogen in the air can combine with the air fuel mixture to produce Oxides of Nitrogen–a key component of smog. To reduce combustion chamber temperatures, the EGR valve opens and sends in a ballast charge of exhaust. Because sending exhaust into the mixture at idle would choke the engine, this is usually done when the engine … Read More

P0401 EGR insufficient flow – Chrysler Minivan

Fix trouble code P0401 egr insufficient flow – Chrysler Minivan Late model Chrysler Minivans are known to post P0401 egr insufficient flow codes P0401-P0408. The egr valve is like an electronic solenoid that pulls the pintel off its seat. A position sensor at the top of the valve measures how far the pintel shaft has actually moved versus how much the computer commanded it to move. It’s the position sensor that goes bad (see plunger in photo). The problem may be in the sensor, but the fix is in replacing the … Read More

P0401 P1408 — Ford

Fix trouble codes P0401  P1408 on a Ford vehicle Fords with P0401,  P1408 trouble code are known for problems with their DPFE sensors. These sensors detect the change in manifold vacuum pressure when the EGR is commanded on and off and display P0401,  P1408 trouble codes. If you get an EGR code, DO NOT automatically assume that it’s a bad EGR valve! Get a hand held vacuum pump and apply vacuum to the EGR. Check the operation of the valve. It if moves properly and the passages are clean, move on … Read More

Ford DPFE sensor and EGR System

Fix a Ford DPFE EGR sensor problem The Ford DPFE and EGR systems are unique and you must understand how they work if you want to diagnose and fix them. This article explains how DPFE works with the EGR system on Ford vehicles. Car makers recycle exhaust gas back into the engine to reduce combustion temperatures and pollutants. However, in order to make the engine run smoothly car makers have to meter the recirculated exhaust, injecting it into the intake manifold only under the proper conditions. To do that, they … Read More


Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN