2000 Ford Mustang GT Problems

What owners report

Owners of this 2000 Mustang GT most often describe stalling and rough idle, with many linking the problem to the idle air control valve. Other recurring themes are intake manifold cracks with coolant leaks, spark plugs blowing out or stripping threads, and seat belts that stick or fail to retract. Intake manifold reports mostly appear at 100,000 miles or more, while the stalling reports in the sample are at lower mileage, and many complaints do not record mileage.

1. 1
   Vehicle speed control

   Stalling and rough idle, often tied to the IAC valve

   • 14 complaints (22%)
   • median 20,000 mi at 4.0 yrs old (9 state mileage, few)
   • filed 2002–2012

   Owners describe the engine stalling at stops, when slowing or turning, or while driving, along with a rough or rolling idle and trouble starting or keeping the engine running on a cold start. Many link these symptoms to the idle air control (IAC) valve, and some say the valve was replaced more than once. Some describe losing power steering or power brakes during a stall, which they say made the car hard to control. According to complaints, dealers replaced the IAC valve in some cases, recommended reprogramming the computer in others, and a dealer said such failures are expected on certain Ford models. Reported from about 1,000 to 52,000 miles, and many complaints in this group do not record mileage.

   What to check: On a test drive, check for a rough or unstable idle at a stop and for stalling when slowing down. Ask whether the idle air control valve has been replaced and whether any repeat replacement or computer reprogramming is on record.

   2 excerpts from owner complaints in NHTSA records

   “The iac on my new mustang went bad. At first Ford wouldn't cover it but the car was less than 90 days old. The one they installed went bad after 10 days also and so did the following one after 90 days. The last one went bad just before the warranty went up and now I keep a spare and change it about one every couple of years.”

   NHTSA complaint #10478719, filed 2012-10, 1,000 miles

   “The iac valve keeps going bad in my 2000 Ford Mustang Gt. I have had to have it replaced by my local shop for $300 each (including the tow to the shop since the car was inoperable).”

   NHTSA complaint #10025347, filed 2003-07, 32,000 miles
2. 2
   Engine cooling

   Intake manifold failures and coolant leaks

   • 10 complaints (16%)
   • median 125,000 mi at 12.4 yrs old (7 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2002–2018

   Owners describe the plastic intake manifold, or a plastic piece connected to it, cracking or breaking, with coolant leaking onto the engine or into the spark plug wells. Some report overheating, steam from under the hood, or a stall while driving, and some say the engine misfired badly on the highway. Some say the whole intake had to be replaced, and some owners say the manufacturer stated their car was outside a voluntary recall for the intake, even though they say the part matches the recalled one. Reported from about 42,500 to 146,000 miles, and most known-mileage reports are at 100,000 miles or more.

   What to check: Check the intake manifold and its hoses for cracks, dried coolant residue, or a sweet smell under the hood. Ask whether the plastic intake has been replaced and whether a recall check has been run using the vehicle identification number.

   2 excerpts from owner complaints in NHTSA records

   “While driving vehicle, engine began to overheat. Steam rolled from under the hood. Discovered crack in manifold where it connects to thermostat housing. Coolant dripping on the engine; I do not know if internal components are damaged. Researched it online and found that there was a recall on this model and that Ford corrected this in subsequent models by changing manifold to aluminum from the plastic. Ford will not honor recall for my vehicle. …”

   NHTSA complaint #10547309, filed 2013-10, 140,000 miles

   “Driving down interstate when started smelling antifreeze. Thought it was coming from a car in front of me. All gauges were fine with no indication of an engine problem. I drove for several miles before I began to notice engine trouble. By this point all the water had been pumped out of the motor. All engine gauges continued to read fine. After pulling off side of the road and diagnosing the problem I discovered that the heater hose outlet on top of fords plastic intake had broke off. …”

   NHTSA complaint #10352987, filed 2010-08, 127,000 miles
3. 3
   Engine cooling

   Spark plugs blowing out or stripping threads

   • 10 complaints (16%)
   • median 87,000 mi at 8.6 yrs old (9 state mileage, few)
   • filed 2005–2011

   Owners describe a spark plug blowing out of the cylinder head or popping out of its socket while driving, with a loud bang, misfire, and sudden loss of power. Some say the threads in the cylinder head stripped, which they say calls for a new head or a thread repair, and others say a plug blew out again after it had been replaced. Complaints report that Ford called the failure rare, while other complaints say owners were told it is a common problem for these engines. Reported from about 40,000 to 96,600 miles, with most at 70,000 miles or more.

   What to check: Ask whether the spark plugs have been checked or replaced and whether the threads in the cylinder head were ever repaired. On a test drive, note any misfire, rough running, or loud popping under acceleration.

   2 excerpts from owner complaints in NHTSA records

   “My 2000 Mustang Gt blew out a sparkplug while on the highway going about 45 miles per hour. This engine has about 40,000 miles on it. It was bought directly from Ford to replace more first engine after 160,000 miles. This is the 2nd engine Ford sent to replace my old engine. The 1st replacement engine blew out a sparkplug on initial startup in the repair shop.”

   NHTSA complaint #10276733, filed 2009-07, 40,000 miles

   “(1)normal driving no racing just normal driving (2)my spark plug stripped out the threads in my head of my 2000 Mustang Gt now I need to replace cylinder head or have it helicoiled. The design of the head is at fault in my opinion, there isn't enough threads on the cylinder head to properly hold the spark plug in place. (3) have not been able to repair due to cost.”

   NHTSA complaint #10144796, filed 2005-12, 57,054 miles
4. 4
   Seat belts

   Seat belt retractors that stick or fail to retract

   • 6 complaints (9%)
   • median 95,000 mi at 7.6 yrs old (6 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2005–2018

   Owners describe seat belts that fail to latch, lock partway, or will not extend or retract fully, sometimes after the belt was already replaced. Some say the belt caught in the door and chipped paint, and another describes a belt that failed again after a rear-end collision that deployed the airbags. According to complaints, the belt was replaced under warranty in some cases, and in others the dealer or manufacturer said the vehicle was not part of a recall. Reported from about 10,000 to 106,000 miles, with most known-mileage reports at 69,000 miles or more.

   What to check: Pull each front seat belt out fully and let it retract to check for sticking, locking, or slow retraction. Ask whether any belt has been replaced and whether the dealer has confirmed the vehicle is outside a seat belt recall.

   2 excerpts from owner complaints in NHTSA records

   “My car was parked in a parking lot. My friend took off his seat belt and as it was retracting, it locked. I tried to pull on it to see if it would unlock and it will not budge one bit. It is locked about half ways.”

   NHTSA complaint #11119523, filed 2018-08, 106,012 miles

   “Takata recall. The drivers side seat belt was replaced under warranty the first time, as it was failing to return to default position properly. The seat belt was replaced a second time, after I was rear ended (it was failing to retract again at the time, identical to the first time I had to have it replaced under warranty), and crushed into the vehicle in front of me. I was at a full stop when the vehicle hit me from behind. That crash deployed both airbags. The front and rear bumpers were replaced due to that crash, along with the seat belt. …”

   NHTSA complaint #11149915, filed 2018-11, 100,000 miles

Buying note. For a buyer considering this model year, ask for records of idle air control valve and intake manifold repairs, and check whether any spark plug or seat belt work has been done. A test drive with a cold start, a stop in traffic, and a seat belt check can show whether the stalling and related symptoms described above are present.

Summary written with AI from a sample of 59 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.