Engine Diagnostics
Engine diagnostics is a structured fault-finding job: we read every control module, watch live engine data, then confirm the suspect part with a physical test. It is the right first step when the engine runs badly but you do not know why, whether or not a warning light is on.
From AED 150Written quote after diagnosis, before work startsConvenience fee applicable · shown on your written quote
- 2-4 hours; deeper mechanical tests may need the car overnight
- Pickup and delivery from your door
- Convenience fee applicable · shown on your written quote
- Diagnosis free with repair
Signs you need engine diagnostics
- The engine idles unevenly or the revs hunt up and down at traffic lights
- It hesitates or stumbles when you press the accelerator, mostly when the engine is warm
- Fuel use has crept up and you are filling the tank more often than before
- There is a ticking, knocking or rattling that was not there last month
- Long cranking before it starts, or it starts and then dies
- A warning light that comes and goes, or no light at all but the car just feels wrong
What usually causes it
Ignition and fuel delivery wear
Worn spark plugs, tired coils, partly blocked injectors or a weak fuel pump all show up as the same rough-running feeling. Fuel trim values and misfire counters in the live data tell them apart.
Air and vacuum problems
A cracked intake hose, a dirty mass airflow sensor or a leaking vacuum line lets the engine breathe unmetered air, which confuses the fuelling. Smoke testing the intake finds leaks you cannot see.
Mechanical wear inside the engine
Low compression from worn rings or burnt valves, a stretched timing chain or a failed mount produce symptoms that no scan code names directly. These only appear in compression and leak-down tests.
Sensor and wiring faults
A crankshaft or camshaft sensor with a weak signal, or a chafed wire under the manifold, causes intermittent stalls. The fault often disappears when the engine is cold, so the technician looks at logged data rather than waiting for it to repeat.
How we do engine diagnostics
- 1
Interview and visual check
You tell us when the problem happens: cold, hot, under load or at idle. We check oil level and condition, coolant, belts and obvious leaks before connecting anything.
- 2
Full-system scan
Every module is read, not just the engine computer, because a transmission or ABS fault can set engine symptoms. Stored and pending codes plus freeze-frame data are recorded.
- 3
Live data and testing
We log fuel trims, ignition timing, sensor voltages and misfire counts while the engine runs, and add compression, leak-down, fuel pressure or vacuum tests where the data points to them.
- 4
Written findings and quote
You receive the confirmed fault, the parts and labour needed, and your choice of OEM, aftermarket or used parts on the quote. Nothing is repaired until you approve it.
In Dubai, Sharjah and Ajman
Dubai engines work harder than the brochure assumes: idling for ages with the AC on, crawling on Sheikh Zayed Road and sitting in 45 degree heat all raise oil and coolant temperatures. Faults that stay hidden in a mild climate show up here, which is why we test the engine hot as well as cold.
Questions about engine diagnostics
Is diagnosis charged if I do not repair with you?
Diagnosis is free if you go ahead with the repair, and charged if you take the findings elsewhere. The charge is stated on the quote before we start.
Can you diagnose a car that will not start?
Usually yes. We arrange pickup and delivery of the car, then test fuel, spark and compression to see what is missing.
Will the scan alone tell you what to replace?
Not reliably. A code points to a circuit, not always to the part, so we confirm with a measurement before recommending anything. This avoids paying for parts that were never faulty.
How is this different from a check engine light scan?
A light scan starts from a code. Engine diagnostics also covers cars with no light, where the complaint is a feeling, a noise or poor economy, and it includes physical tests such as compression.
Last updated
Get a written quote
Tell us about your car. You get an itemised quote before any work starts, and you choose OEM, aftermarket or used parts.