Code P0401 How to fix it!

OBDII Trouble code P0401 is an EGR code. More specifically it is insufficient flow. In this case the computer does not detect enough EGR flow. Exhaust Gas Recirculation. If you take a systematic approach you can quickly identify the problem. The first thing I always do is verify that the EGR is capable of working. On vacuum controlled valves it is as simple as applying vacuum to the valve at idle. If the engine stumbles or dies then you know the EGR is capable of working. If nothing happens then you either have a defective valve or the passages are clogged by carbon deposits. This is a very common problem. If the engine does stumble or die then you have another problem. Either the computer cannot control the EGR, possibly a defective vacuum switching valve, or a vacuum hose is split or somehow leaking vacuum, or the valve is working but the computer does not detect it is working. In that case you possibly have a defective lift sensor, or EGR temp sensor. Or you could have a wiring problem or loose ground. The list goes on and on. This will at least give you idea where to start. Hope this video helps...

Category:

Autos & Vehicles

Tags:

• Auto Repair
• P0401
• EGR
• egr
• obdII
• obd2
• insufficient egr flow
• diagnostics
• How-to

[Rdrake1413]

Nice work