What people keep running into with engine repair
Complaints tagged engine repair, each raised by more than one person. One-off posts are not included.
60 recurring problems · 890 people · 7 forums we read
Raised more than once
Most people first.
- 168Vehicle cranks after fuel pump replacement but won't startA replacement fuel pump can deliver pressure while flooding the engine with excess gas, preventing it from catching. This leaves the vehicle cranking normally but refusing to start or run.
- 94How to figure out what an unfamiliar car engine noise isUnfamiliar engine noises like chattering, squeaking, or sounds that change when you turn the steering wheel make it difficult to figure out what is broken. Without knowing the source, car owners cannot tell if the vehicle is safe to drive or what repairs are needed.
- 74Why does my car make a loud rattle when starting the engine?An engine startup rattle indicates a mechanical noise occurring immediately upon ignition. This issue stops the engine from idling smoothly and can cause severe shaking throughout the vehicle cabin.
- 54How to identify a random car part that fell offRandom car parts found on the road or dropped from a vehicle can leave drivers unsure if their car is unsafe to drive or if they simply hit debris. Without knowing the part's name or function, vehicle owners struggle to figure out if it belongs to their car or an obstacle they ran over.
- 38How to find a hidden engine oil leak spraying on componentsWhen an engine oil leak sprays onto moving components like the CV joint, it covers surrounding areas and makes tracing the original source difficult. Even after replacing common problem spots like gaskets, the residual mess prevents drivers from easily identifying where the new or ongoing leak is originating.
- 28Why does my car run terribly and stutter after a long drive?Extended driving triggers severe engine sluggishness, unusual valve train noises, and random cylinder misfire codes. These sudden performance drops cause RPM stuttering and electrical warnings that leave drivers stranded and unable to reach a diagnostic scanner.
- 28Why are my oxygen sensor readings going crazy during a misfire?Conflicting lambda readings ranging from very rich to ultra-lean make it nearly impossible to pinpoint the root cause of an engine misfire using standard data alone. This erratic sensor behavior prevents car owners from identifying whether the issue stems from failing injectors, fuel delivery problems, or sensor faults.
- 27Is it safe to keep driving with needle bearings in the transmission pan?Finding needle bearings on the transmission magnet of a high-mileage vehicle indicates internal component failure that threatens reliable operation. Owners face the difficult choice of whether to pay for a major repair or risk driving the car until it completely breaks down.
- 25Why does my car stall when I come to a stop?Vehicles sometimes shut off or shake and drop RPMs when coming to a stop sign, red light, or while reversing early in a drive. This happens even with accessories like the AC and radio turned off, leaving drivers uncertain about mechanical issues while a persistent P0328 code returns.
- 25Why is my car burning a quart of oil every 500 miles?High oil consumption often leads to burning about a quart of oil every 500 to 1,000 miles, accompanied by blue smoke under load and a rough idle. This excessive oil loss prevents drivers from maintaining reliable engine performance without constantly adding oil.
- 23Why does my car engine cut out after driving for a while?An engine can die after thirty to forty minutes of driving, behaving as though it is out of fuel despite a full tank, and then refuse to restart for an hour or two until it cools down. This sudden loss of power and shutdown leaves drivers stranded and unable to rely on their vehicle for daily use.
- 23Why does the check engine light come back on after replacing a sensor?When a persistent check engine light returns shortly after a sensor repair, it usually means the underlying fault—such as a failing catalytic converter or timing issue—was not fully resolved by replacing the component alone. This leaves drivers anxious about whether their car is safe to drive and unsure what to check next.
- 19Metal flakes in engine oil after buying a used carFinding metal bits or debris in drained engine oil indicates internal engine wear or component failure. This discovery often signals a hidden mechanical problem that requires immediate investigation before the vehicle can be safely driven.
- 19Is it safe to drive with too much engine oil?Putting too much oil in an engine creates uncertainty about whether it can be driven safely or needs to be drained immediately. This leaves drivers anxious about whether they can make it to work or a shop without damaging their vehicle.
- 18How to tell if car suspension bushings need to be replacedWorn suspension bushings often show physical separation or cause unwanted noises that are difficult to identify visually without experience. Determining whether the wear requires an immediate repair or can wait a few weeks prevents unnecessary panic while ensuring vehicle safety.
- 17Why am I paying for broken bolts during a car repair?Repair shops and dealerships often break rusted or seized parts during standard service, yet charge vehicle owners to extract or replace them. This leaves customers footing the bill for damage that wasn't there when they dropped off the car, while shops refuse to absorb the labor required to handle stubborn factory components.
- 17Why does a car shake when idling after sitting for years?Vehicles left sitting unused for long periods often develop heavy vibrations in gear and reverse upon startup, leaving owners stranded without knowing where to begin troubleshooting. This makes it difficult to restore an older vehicle to a drivable state without wasting money on random parts.
- 15How to tell if a worn timing belt actually needs replacingMechanics often recommend replacing worn timing belts immediately, but vehicle owners frequently debate whether the belt can safely run past its mileage limit. Delaying this $1,500 repair risks catastrophic engine failure if the belt snaps, yet changing it early may mean throwing away thousands of miles of remaining life.
- 11Why did my low mileage engine fail?Catastrophic engine failure at low mileage can result from severe internal mechanical damage, such as a failing connecting rod trying to break through the block. This leaves owners facing expensive total engine replacements or swaps instead of simple repairs.
- 10Camshaft timing looks off by a tooth but engine ran fineCamshaft timing marks can look misaligned or off by a single tooth depending on the visual angle and chain link placement, leaving mechanics unsure whether to leave the setup alone or adjust it. This uncertainty makes it difficult to confirm if the phaser placement and chain alignment are correct without clear, multi-angle reference photos.
Comes up alongside
Topics that keep appearing on the same problems — not topics with similar names.