Diesel Repairs Norwich

Modern diesels are excellent at what they were designed for, long journeys at steady speed, and miserable at what many Norwich drivers actually do with them, five-mile trips across the city with the engine never fully warm. The result fills our diary: diesel particulate filter warnings, EGR valves clogged with soot, AdBlue systems counting down to a no-start, turbos that have lost their boost and cars stuck in limp mode on the A47. At Ber Street we diagnose diesel faults properly with manufacturer-level diagnostics, repair them the legal way (no filter removals, no emissions "deletes", no remaps to hide a fault), and tell you honestly how to stop the same problem recurring, including, sometimes, that a diesel is the wrong car for your driving.

Diagnosed firstthe fault found before it is quoted

Quoted before worknothing added without your say so

3-month guaranteeor 3,000 miles on workmanship

Open 7 daysfree parking on site

Diesel Particulate Filter (DPF) Faults

The DPF traps soot and burns it off when the exhaust is hot enough for long enough. Short urban journeys never get there, the filter fills, and the warning light comes on. What happens next depends on how quickly you act:

• Amber DPF light, car driving normally. Often a good run at a steady 50 to 60 mph for 20 to 30 minutes will let the car regenerate on its own, if nothing else is wrong. If the light stays on, it needs looking at.
• DPF light plus engine light or limp mode. The filter is too full for the car to regenerate itself, or a sensor, glow plug, EGR fault or injector problem is stopping it. We read the soot loading and the fault codes, fix whatever is preventing regeneration, and perform a forced regeneration with diagnostic equipment where the filter is within limits.
• Filter beyond regeneration. A filter that is blocked with ash rather than soot, or has been driven full for too long, cannot be regenerated. We can arrange off-car cleaning through a specialist service where that is viable, or replace the filter with a quality unit. You get both options and the honest difference between them.

We also check the things that cause DPF trouble in the first place: the wrong (high-ash) engine oil, a lazy thermostat that never lets the engine warm up, a faulty differential pressure sensor, or a leaking injector loading the filter with soot. Fixing the cause is what stops the light coming back. Read the DPF care guide for what you can do yourself.

EGR Valve Faults

The exhaust gas recirculation valve feeds a measured amount of exhaust back into the intake to lower combustion temperatures. On short-journey diesels it chokes with soot and sticks, causing rough idle, hesitation, black smoke, poor economy, an engine light and, on many cars, a DPF that cannot regenerate. We diagnose whether the valve is sticking, the cooler is leaking or the wiring and control are at fault, then clean or replace the valve as the condition warrants. A carboned-up intake manifold behind it is checked at the same time on engines known for it.

AdBlue (SCR) System Faults

Diesels with AdBlue inject urea solution into the exhaust to cut nitrogen oxides, and when the system detects a fault it starts a countdown of miles or starts after which the car will not restart. Common causes are a failed NOx sensor, a crystallised or blocked AdBlue injector, a faulty tank heater or level sensor, a pump fault, or simply the wrong fluid or contamination in the tank. We diagnose which, repair or replace the component, clear the countdown properly, and check the whole system is dosing correctly afterwards. Do not leave an AdBlue countdown to the last few miles; once it reaches zero the car cannot be started until it is repaired. See the AdBlue guide.

Good to know

Can you clear my DPF warning light? We can, but clearing the light without fixing the cause is pointless. We read the soot loading and fault codes, fix whatever is stopping regeneration, and perform a forced regeneration where the filter is within limits.

Injectors, Turbos, Glow Plugs and Limp Mode

• Injectors. Rough running, knocking, white or black smoke, a diesel smell, poor starting and a filling DPF. Tested for leak-back and balance before anything is replaced.
• Turbochargers. Loss of power, whistling, blue smoke, oil in the intercooler pipes or limp mode under load. Often a sticking variable-vane mechanism, a boost leak or a control actuator rather than the turbo itself; we find out which first. See the turbo care guide.
• Glow plugs. Hard cold starts and white smoke on winter mornings, and on many cars a failed glow plug also stops DPF regeneration.
• Limp mode. The engine protecting itself from a fault it has detected. The fix is to read and understand the fault, not to clear the light and hope; see car diagnostics.
• Fuel system: fuel filters, low-pressure pumps, and the damage done by misfuelling or contaminated fuel; see the fuel filter guide.

What We Will Not Do

We do not remove DPFs, disable EGR valves, delete AdBlue systems or remap a car to hide an emissions fault. It is illegal to drive a car with its DPF removed, it is an automatic MOT failure, it can invalidate insurance, and it is a poor fix that moves the problem elsewhere. If a garage offers you a "DPF delete" as a cheaper option, it is offering to make your car illegal. We repair diesels properly, and if the honest answer is that your driving pattern will keep blocking the filter, we will say so and help you weigh the alternatives.

Servicing That Prevents Diesel Faults

Most of the diesel faults above are prevented by the right servicing: the correct low-ash (low SAPS) oil at the right interval, a fuel filter changed on schedule, a thermostat that lets the engine warm up, glow plugs that work and a good run every so often. Our full service covers the lot for diesels, and our make pages for Volkswagen, Ford, BMW, Land Rover and Peugeot and Citroen cover the engine families we see most. Vans doing town deliveries suffer most of all; see van servicing.

Call 07933 900901 with the registration and what the dashboard is showing. Open seven days, free parking at 100-106 Ber Street, 3-month / 3,000-mile workmanship guarantee.

How a Repair Works Here