87 of the
702 complaints filed about the Porsche Cayenne
are about the engine —
12% of everything owners reported.
The worst model year for it is 2011.
Nearly 25% of the total time I have owned this Certified Pre-Owned vehicle (146 out of 564 days), it has been non-functional and in the shop — roughly 1 out of every 4 days of ownership. I am a [XXX} with a [XXX] child, and I purchased this vehicle as a Certified Pre-Owned (CPO) Porsche — expecting the manufacturer's rigorous inspection and warranty to ensure reliability and safety. Instead, the first breakdown occurred within just 1 month of purchase, and the vehicle has since failed six separate times over 18 months (Feb 2025–Aug 2026), totaling 60+ days out of service, despite extensive component replacement: [XXX] (≈1 month after CPO purchase) – Battery failure; car would not start; towed at 2–3 AM. [XXX] – No-start; fuel tank drained/refueled ("improper additive"). [XXX] – Low fuel pump replaced. [XXX] – High fuel pump, all 6 fuel injectors, DME system replaced. [XXX] – Recurring no-start; repurchase denied May 7, 2025; Porsche later claimed root cause found (mechanical part) and replaced it. Aug 1, 2026–ongoing – Check engine light returned; misfire on cylinder 4 and coolant leak into vacuum system found. Dealer replaced coolant pump/vacuum components, updated DME software — check engine light reappeared on the dealer's own test drive. Why This Is Especially Dangerous: A CPO vehicle should not fail this quickly or repeatedly. It raised serious concern that either the inspection was inadequate or a pre-existing defect was never disclosed. My child rides in this vehicle regularly. A sudden stall or power loss at highway speed, at an intersection, or during school pickup/drop-off could cause a serious collision, endangering my child's life and my own. As a [XXX] with no backup driver/vehicle, an unexpected breakdown have cost lost work time, unreimbursed Uber expenses, and childcare disruptions. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11756293 — an unverified report by a vehicle owner.
2019 Porsche Cayenne Turbo (EA825 4.0L V8, VIN [XXX]). Vacuum-actuated water pump seal failure caused coolant infiltration of the vacuum system on two separate occasions during the CPO warranty period. The vacuum system on this engine supplies the brake servo (brake booster) — a safety-critical connection documented in Porsche and Audi's own engineering literature for this engine (NHTSA document MC-XXX). First failure: XXX (92,916 miles, RO XXX). Towed in overheating. Technician documented coolant infiltrating vacuum system. Coolant pump replaced. Vacuum lines not inspected or replaced. Vacuum pump not inspected or replaced. PCNA's own ATI 2235.1 (NHTSA MC-XXX) required vacuum line inspection — not performed. Second failure: October 3, 2025 (103,904 miles, RO 207205). Coolant documented at timing chain cover. Coolant pump replaced. Change-over valve not replaced — required unconditionally by ATI 2235.1. Vacuum lines not inspected or replaced. No PQIS fault code logged — required by PCNA TSB 2307 (NHTSA MC-XXX). No oil analysis performed. No timing chain cavity inspection. Service visit performed one month before CPO expiration. Third visit: XXX (103,988 miles, RO XXX). Cracked breather hose found 84 miles after second service. Vacuum system still unremediated. Current failure: March 2026. Severe valvetrain noise on cylinder bank 2. Engine-out diagnosis required. Estimate $13,286.57. Vehicle currently at Porsche Novi/Farmington Hills. PCNA denied coverage June 25, 2026 without referencing a single technical bulletin, repair order, or published protocol from the documented record. The brake servo vacuum supply connection — documented in PCNA and Audi's own engineering literature — makes this a safety matter. PCNA's own TI 173/21 (NHTSA MC-XXX) explicitly covers the V8 Biturbo variant and was not followed. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11747045 — an unverified report by a vehicle owner.
The hybrid cooling system on my 2019 Porsche Cayenne E-Hybrid repeatedly displayed a red dashboard warning while the vehicle was in motion: "Hybrid coolant level too low / Park vehicle safely / Let vehicle cool down." This warning appeared on multiple occasions at speeds of approximately 22 mph, 38–40 mph, and 47 mph, as documented in timestamped photos and videos taken in November 2025. A separate warning in July 2025 read: "Engine cannot be started / Remove charger plug." The warnings indicate a potential thermal management or hybrid cooling system failure. A moving vehicle being instructed to park and cool down presents a safety risk to the driver and others, particularly if the condition causes sudden power loss or thermal event. The vehicle was serviced at an authorized Porsche dealer in 2025. Despite that service activity, the hybrid coolant warning recurred while driving in November 2025, suggesting the underlying condition was not fully resolved. The issue was reported to the manufacturer (PCNA), who acknowledged it under a case number and offered a service voucher. The selling dealer attributed the concerns to a manufacturer charging-cable campaign. Neither response addressed the recurring in-motion warning or confirmed the hybrid cooling system was repaired. Timestamped photo and video evidence is available showing the dashboard warnings and vehicle speed at time of occurrence. Complete repair orders have been requested but not yet provided. The component may be available for inspection upon request.
NHTSA complaint #11745533 — an unverified report by a vehicle owner.
"Engine temperature too high. Park vehicle and allow engine to cool". warning at 50,000 miles which the mechanic says this is a huge problem with all Porsche, Audi and VW due to water coolant changeover valve which fails and also stated that Porsche is aware and should have a "bulletin" open on this issue?
NHTSA complaint #11740164 — an unverified report by a vehicle owner.
The contact owns a 2022 Porsche Cayenne. The contact stated that an abnormal tapping noise was coming from the engine compartment. No warning lights were illuminated at the time of the failure. The vehicle was initially taken to an independent mechanic, who confirmed the tapping noise and referred the contact to an authorized dealer for further inspection. The vehicle was then taken to local dealers, who acknowledged the noise but advised that the vehicle was operating as designed and that the condition was considered normal. The vehicle was not diagnosed or repaired. The vehicle was later taken to New Country Porsche Greenwich Service Center, 241 West Putnam Avenue, Greenwich, CT 06830, but the vehicle was not diagnosed or repaired. The tapping noise continued to persist over time. The manufacturer was contacted and confirmed that there was no warranty coverage. The failure mileage was approximately 40,000.
NHTSA complaint #11738004 — an unverified report by a vehicle owner.
This vehicle qualified for the Volkswagen Emissions Recall, yet from the start of the recall through 2018 settlement lawsuit dates , no correspondence was sent (by Porsche nor VW). According to all recall regulations, my vehicle should have among the ‘recall’ with the 85K plus others, yet no correspondence was sent (by Porsche nor VW) & now the local Porsche dealership is denying in, According to all recall regulations, even still with the EPA, the vehicle was to receive an initial emissions test, then undergo all related repairs/part replacements before the issue resulted in toxic emissions, NOX sensor failures, & premature problems with the DPF system, leading to thermostat problems & the failure of the diesel turbo. Federal regs mandate that vehicle & vehicle equipment manufacturers comply with Early Warning Reporting requirements, submit to NHTSA copies of their manufacturer communications. & update all communications including warranty, policy extensions & product improvement communication sent to dealers, distributors, owners, purchasers, etc. regarding any defect, failure or malfunction beyond normal deterioration in use, failure of performance, flaw or other unintended deviation from design specifications whether it is safety-related or not. Porsche now says my vehicle never showed the recall, despite court mandates that all affected vehicles will be notified communication failed on the sides of both manufacturers. In 2026, if one possesses an eligible vehicle but never received a "Dieselgate" recall notice, options for financial compensation from the original U.S. settlements stated to be likely limited, & I’m not able to find how to proceed with Volkswagen, but regardless, according to EPA and all vehicle standards, I read my vehicle is still entitled to receive an emissions modification at no cost, and that I should be covered by an extended emissions warranty to address all current & related issues.
NHTSA complaint #11724527 — an unverified report by a vehicle owner.
A coolant hose located on the top of the engine developed a leak that caused the engine to overheat. It was necessary to remove several components of the engine to reach and replace the leaking hose. This repair cost over 5000 dollars with the associated labor cost. Vehicle had less than 6000 miles on it at the time of the incident. It took several weeks to get the needed parts.
NHTSA complaint #11721832 — an unverified report by a vehicle owner.
I am reporting a series of safety-related defects involving the electrical, cooling, and fuel systems of my 2021 Porsche Cayenne E-Hybrid. The vehicle was initially brought to the authorized Porsche dealership due to an electrical system error, and the dealer kept the vehicle for an extended period. After approximately five months, the vehicle was returned to me without a clear explanation of the root cause or details of the repair. The very next day after receiving the vehicle, a coolant temperature warning appeared while driving, indicating abnormal engine overheating. This created an immediate safety hazard, as overheating can lead to sudden engine failure, loss of power, or a potential fire risk. I returned the vehicle to the dealership again for further repairs. Afterward, another serious issue occurred: because this is a hybrid vehicle, I went to refuel, but the fuel door would not open, and a fuel system error warning appeared again. This made the vehicle unsafe to operate, especially while already on the road. Due to these repeated failures, I was required to tow the vehicle multiple times. These problems — electrical malfunction, coolant overheating during driving, fuel system errors, and a non-functional fuel door — occurred repeatedly even after prolonged service by the dealership. The combination of electrical faults, overheating risk, hybrid system malfunction, and fuel system failure presents a significant safety concern. I will provide additional documentation to support this report. I request that NHTSA review this case to determine whether an investigation is warranted, as these issues may indicate a broader defect affecting this model.
NHTSA complaint #11703739 — an unverified report by a vehicle owner.
While driving my 2019 Porsche Cayenne S on the freeway, the check-engine light came on, followed by a message on the dashboard that read “Engine Control fault – Driving permitted – Visit workshop.” Moments later, the vehicle suddenly lost power and decelerated from about ~75 mph to around 55 mph, even though my foot was still on the accelerator. I am [XXX] pregnant and had our [XXX] child in the car at the time. The unexpected loss of speed in fast-moving traffic was frightening. I had to quickly change lanes to reach the slower lane and avoid being hit by other vehicles. After reaching safety, I drove the car to an authorized Porsche dealership, where technicians found an active water-pump leak with coolant entering the vacuum system, which may have caused turbocharger and engine-power failure. This is after I replaced the water pump last year at another porsche dealership. A photo taken during the incident shows the dashboard warning message as it appeared. This incident created a serious safety hazard, as the vehicle displayed “driving permitted” even though it was at risk of a sudden loss of propulsion at highway speeds. The car and the failed components are available for inspection. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11698394 — an unverified report by a vehicle owner.
There is a major issue with the coolant pump/water pump on the V8 4.0L engine. Every 30,000ish miles I’ve had to have a water pump replaced in my vehicle, Porsche NA claims they redesigned the pump and it fails in the same amount of time. Rennlist Porsche worldwide forums there are 28 threads of people having water pumps/coolant pumps replaced at the tune of $9,000-$12,000 because 70-80% of the front end of the Cayenne has to be removed to get to the water pump. The pump needs to be made out of more durable materials for durability and longevity. Expecting customers to replace water pumps every 30K miles is ridiculous. My 3rd water pump in 95K miles is being replaced as I type this right now. The dealership Porsche of Wallingford, CT, has 3 other customer Cayennes now that also need water pumps. Porsche USA and AG/Germany need to issue a 15 year/unlimited miles warranty on this water pump, like they’ve had to do with window switches, emissions valves, and other parts they have gotten sued for and now have 15 year warranties.
NHTSA complaint #11668197 — an unverified report by a vehicle owner.
Engine oil leak detected in 2021 @33,195 miles caused by broken aluminum bolts in upper part of timing cover. Repaired by dealer on a “good will” basis for what I was told would have cost me approximately $9-10,000. Oil leak reappeared in 2023 @44,657 miles (less than 12,000 since first leak) caused again by broken aluminum bolts in the lower, upper oil pan, and timing cover. Repair done this time by independent shop at a cost of $6,865.70.
NHTSA complaint #11627258 — an unverified report by a vehicle owner.
The car is very jerky, I bought in for engine or transmission mount because the idle shakes the whole car. They said its normal. Which I don't think it's normal.
NHTSA complaint #11621314 — an unverified report by a vehicle owner.
When car downshifts from 2nd gear to 1st gear, it lunges / jerks forward, even as brakes are applied. Porsche mechanic and Porsche Cars North America both indicate nothing is wrong with the transmission. THIS IS A CONSTANT ISSUE. EVERYDAY FOR THE LAST TWO WEEKS. EVERY STOP.
NHTSA complaint #11609566 — an unverified report by a vehicle owner.
Broken and loosened timing chain cover bolts resulting in leaking oil onto drive components, belts and tires/brakes. This recall was done for the Macan and not the Cayenne. Ours was covered under factory extended warranty. That said, this is criminal. Porsche needs to be investigated, they refuse to recall their vehicles and we all know there are some manufaturing issues that are 100% the factory's fault. If the NTSB refuses to hold their feet to the fire this type of engineering will continue.
NHTSA complaint #11592066 — an unverified report by a vehicle owner.
My vehicle has camshaft and crankshaft correlation problems due to the well-known problem with its screws and other things. I reported it to Porsche and they told me that it has already been repaired but I don't understand how to fail again and deny help for its repair.
NHTSA complaint #11584086 — an unverified report by a vehicle owner.
car had a smell of gas diesel fumes inside cabin from air conditioning system. number of oil leaks over the years as well. now car at dealer for repair over 10 month. not fixed yet. number of problem with same diesel engine on line, even article i found . car was sold as CPO , it was new unregister, but they guaranteed us there will be no emission problems or leaking with this car. now warranty almost over Nov 2023 , and I will get a defective car back maybe... after warranty will expire! more importantly a car that leaks oil or diesel and smells inside the cabin from that.
NHTSA complaint #11543209 — an unverified report by a vehicle owner.
Problem with the hybrid system and the engine control system. Unit changed automatically and unexpectedly from battery power mode to engine power mode when on battery power mode only. This change is not supposed to happen. This failure happened when starting the unit, put on drive and starting to move forward. This failure caused the unit to charge forward with more power unexpectedly. Causing almost to collide. At the time of the failure “engine control system” warning and “e power not available” warning lid up. The unit has been for service for 10 times with the same warnings powering up. At this time the unit has been on service for almost four month.
NHTSA complaint #11531025 — an unverified report by a vehicle owner.
For the past nine years, my vehicle has recorded multiple safety issues (trunk not closing/breaking, check engine light, catalytic converter misfire, keyless electronic entry issues, glow bulb light, turn signal bulb light, windows not rolling up, leaking fluid on the passenger side, burning smell coming from the vents, electrical issues with the radio, sunroof intermittently not opening/closing and the key not turning the vehicle on. Over the past nine years, I have taken the vehicle to numerous Porsche dealerships per the federal mandate from Porsche USA / Porsche UK. To date, the Service Manager, Chris Sansbury and General Manager at Brian Harris Porsche, and Porsche USA, refuse to fix the vehicle. My vehicle is still under factory warranty. I am a person with multiple disabilities. The dealerships (Jim Ellis Porsche, Hennessy Porsche, Leith Porsche, Brian Harris Porsche) have charged me thousands of dollars. I have been extremely sick and desperately need your help. Please help me!
NHTSA complaint #11530716 — an unverified report by a vehicle owner.