Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 1998 Ford Mustang owners, lightly cleaned up (personal details are redacted by NHTSA).
Tl contact owns a 1998 Ford Mustang gt. Approximately fifteen minutes after parking and exiting the vehicle, the engine compartment became engulfed in flames. The vehicle was destroyed. There was damage to another vehicle and to a neighboring home; however, the contact did not know the extent of the damage. A fire report was filed. The VIN and purchase date were unknown. The current and failure mileages were 140,000. Updated 03-04-08 updated 03/04/08
Tl* the contact owns a 1998 Ford Mustang. Immediately after the vehicle was purchased, it was inspected by an independent mechanic. The mechanic diagnosed that the ignition wires and engine needed to be replaced. The mechanic also diagnosed that the vehicle needed to be properly aligned. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 112,000.
Dt*: the contact stated, the engine overheated due to cracks in the head gasket, causing the transmission to slip. There was an accident on 6/20/06 due to the transmission slippage. It was raining and the rate of speed was 30mph. No injuries incurred but minor damage to the other vehicle was reported in the police report.
I recently purchased a 1999 Ford Mustang with a 1998 used engine installed into it. I only had 1 real problem with it and it was my exhaust. I had that fixed and ran great for the next day. Less then 36 hrs after the exhaust was fixed and after sitting for about 15 hrs or so, which was from around 9:45 pm Friday the 21st to around 12:30 to 1:00 pm on the 22nd of August. A neighbor came pounding on our door telling us our car was on fire!!!! He also stated that he heard what sounded like someone was trying to start it from a distance. Well we don't have a remote starter for this car, it only unlocks the car and trunk, does not start it. We believe it was electrical in nature and need to find out what happened as I only had liability ins. And now I have lost my car and have nothing...... I have pictures of my car just melting away, the entire front of it. …
My 98 gt Mustang plastic radiator intake has ruptured at 89,000 miles. It seems all of Ford's equipped with Ford's 4.6l v-8 contain an intake manifold that is prone to failure. Due to original design, this part has a tendency to crack resulting in sometimes over heating, engine failure and worse case damage to other parts of the car's engine. Ford recognizes this problem but will not recall most cars other than fleet vehicles and those listed in the TSB #97m91. 1. 1998 Mustang was overheating while driving down the highway. 2. When car was taken to a repair shop the mechanic noticed a crack in the manifold and advised me to take it to my local dealer. It was brought to my attention that if this part was not corrected engine failure could occur due to coolant loss resulting in severe damage. 3. …
After service of my 4.6 Mustang gt, my car began missing and I had the diagnostic complete it reported a misfire on plug 7 & 8, so I had the plugs replaced. During the replacement, I saw coolant under both the 7 & 8 plug. The misfire continues, and I took it to the dealer they told me the intake manifold had failed and that there is no remedy for the consumer even though Ford is aware of the problem and has a kit to sell to the consumer for 900+ dollars. Fleet cars taxi, crown vic's used by sheriff departments were cleared for replacement, but no the consumer civilian. What sense does that make? If the engineering is bad, and it is, the replacement should be for all owners of the 4.6 liter engine. How is the segregation of fleet cars from personal use vehicles legal in this country? …
Ford automobiles equipped with Ford's 4.6l v-8 contain an intake manifold that is prone to failure. Due to original design, this part has a tendency to crack resulting in sometimes over heating, engine failure and worse case damage to other parts of the car's engine. Ford recognizes this problem but will not recall most cars other than fleet vehicles and those listed in the TSB #97m91. 1. 1998 Mustang was overheating while driving down the highway. 2. When car was taken to a repair shop the mechanic noticed a crack in the manifold and advised me to take it to my local dealer. It was brought to my attention that if this part was not corrected engine failure could occur due to coolant loss resulting in severe damage. 3. Car was taken to local Ford dealership and I gave them the TSB #97m91 and told them to replace the part. …
Vehicle contains a plastic intake maniford that cracks due to the heat and chemicals involved in standard engine use. The cracks allow the escape of radiator fluid/antifreeze ... Which will then cause permenant damage to the engine/vehicle. Ford in fact knows of this problem, and warranties certain vehicle styles/years as well as vehicles used as fleet/police/taxi vehicles ... But not all affected vehicles for consumers that contain the identical part in question. Later vehicle years were fitted with intakes with either aluminum crossovers, or made all of aluminum. Vehicles that contain the failed part have the part replaced with the aluminum-crossover part at the owner's expense. 1.) part fails under regular use of vehicle. 2.) defective part must be replaced at high cost of labor - dealership refuses to repair part despite technical service bullitin #97m91. 3.) nothing. …
We took our 1998 6 cylinder Mustang in for an oil change. It has about 90,000 miles on it. We were told that it is leaking fuel and that it is a safety hazard. We now have to spend $1000 to replace the fuel rail, both valve gaskets, valve cover gaskets and fuel injector o rings. Plus a significant amount on labor. We were told that our car/engine will catch fire, if we do not replace these parts. This is my daughter who is in college's car. How can they have such a horrible design and if we replace the parts is this going to be repeated? The other issue is that there was no warning from an engine light or anything else. The technician checked it because when he looked under the hood, he thought he smelled gas and then found the leak. We hadn't noticed a leak. My daughter could have been killed driving back to school this week.
Coolant was leaking slowly for about eight months, then began to leak a lot the end of December, so the car was undriveable because of risk of overheating, and had to be towed to dealer. It was discovered that the leak resulted from a crack in the plastic intake manifold where the thermostat sits. The dealer replaced the manifold with a new manifold that is metal where the crack occurred (an indication of Ford's awareness of the problem). The cost to replace the intake manifold was $1,070 and I have kept my old manifold. Through my research, I discovered that Ford will replace this part on the 1996-1997 mustangs and police and fleet cars. A memorandum to the dealerships shows that the 1996-1998 mustangs have the same intake manifold part number, so Ford should reimburse me for the cost to replace my intake manifold.
NHTSA investigations
Spark plug ejection from cylinder head
On September 6, 2005, odi received a petition requesting that the agency investigate allegations of engine spark plug ejection in certain model year 1997 through 2004 Ford vehicles with triton v-8 and v-10 engines.odi received a total of 474 non-duplicative complaints on the subject vehicles where the complainant, or the dealer repairing the vehicle, reported that a spark plug detached from the cylinder and/or…
Engine complaints in other Mustang years
Frequently asked questions
How common are engine problems on the 1998 Ford Mustang?
NHTSA has 89 complaints about the engine & cooling of the 1998 Ford Mustang, 30% of the model year's 300 complaints. The component named most often is exhaust system › manifold/header/muffler/tail pipe (25 mentions).
Is there a recall for 1998 Ford Mustang engine problems?
No. NHTSA lists no engine & cooling recall for the 1998 Ford Mustang, though it has 4 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 1998 Ford Mustang engine problems start?
Half of the complaints with a recorded mileage happened before about 90,000 miles, and 2% before 25,000 miles.
Is it dangerous?
Owners linked 4 crashes, 5 fires and 1 injury to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.