Editing Ford Power Stroke engine (section)

==7.3 Power Stroke==
{{Main|Navistar T444E engine}}

The first engine to bear the Power Stroke name, the 7.3&nbsp;L Power Stroke V8 is the Ford version of the [[Navistar T444E engine|Navistar T444E]] turbo-diesel V8. Introduced in 1994 as the replacement for the 7.3&nbsp;L IDI V8, the Power Stroke/T444E is a completely new design, with only its bore and stroke dimensions common with its predecessor (resulting in its identical {{convert|444|cuin|L|1|abbr=on}} displacement). In line with the IDI diesel, the Power Stroke was offered in three-quarter-ton and larger versions of the Ford F-Series and Econoline product ranges.

The Power Stroke is an electronically controlled, direct injection engine with a {{convert|4.11x4.18|in|mm|1|abbr=on}} bore and stroke creating a displacement of {{convert|444|cuin|L|1|abbr=on}}. It has a 17.5:1 compression ratio, and a [[dry weight]] of approximately {{Convert|920|lb|0|abbr=on}}. This engine produces up to {{convert|250|hp|0|abbr=on}} and {{convert|505|lbft|Nm|0|abbr=on}} of torque in [[automatic transmission]] trucks from the last years of production, and {{Convert|275|hp|kW|0|abbr=on}} and {{convert|525|lbft|Nm|0|abbr=on}} of torque in [[manual transmission]] trucks. The oil pan holds {{convert|15|USqt|L impqt|abbr=on}} while the top end (due to the HPOP)<ref>High Pressure Oil Pump, which creates oil pressure to fire the fuel injectors.  The HPOP is responsible for creating injection pressures in a range of 450 to 3,000 psi on 7.3L engines, and 450 to 3,600 psi on 6.0L Power Strokes. The HPOP is controlled by the IPR (Injection pressure regulator) which in turn is controlled by the PCM.</ref> holds an additional {{convert|3|USqt|L impqt|abbr=on}}, making for a total of {{convert|18|USqt|L impqt|abbr=on}} of oil contained within the engine.

The 1994.5 to 1996/97 DI Power Stroke has "single shot" HEUI (hydraulically actuated electronic unit injection) fuel injectors which were AA code injectors unless from California where as they received AB code injectors. It ran a high pressure oil pump (HPOP) to create the necessary oil pressure to fire the fuel injectors. This generation of Power Stroke utilizes an HPOP with a 15° swash plate angle. The 1995-1997 trucks use a two-stage cam-driven fuel pump, whereas the 1999-2003 trucks use a frame rail mounted electric fuel pump. The 1999–2003 trucks also had a deadhead fuel system and a "long lead" injector in cyl. number 8 due to lower fuel pressures with the deadhead design (AE code injector). The California trucks from 1996 and 1997 have a {{Convert|120|cc|abbr=on}} split-shot fuel injectors; other trucks did not get split-shot injectors until 1999. Single-shot injectors only inject one charge of fuel per cycle, whereas the split-shot injector releases a preliminary light load before the main charge to initiate combustion in a more damped manner. This "pre-injection" helps reduce the sharp combustion 'knock' as well as lower [[NOx|NO<sub>x</sub>]] emissions by creating a more complete burn.

1994.5–1997 engines utilize a single turbocharger, non-wastegated, with a turbine housing size of 1.15 A/R. For 1999, an air-to-air intercooler was added to cool the charged air from the turbo for increased air density. With the new cooler, denser air would increase the horsepower potential of the engine, while also reducing [[exhaust gas]] temperatures (EGT). The turbine housing was changed to a .84 A/R and a [[wastegate]] was added halfway through the 1999 [[model year]]. The 1999 engine also received {{Convert|140|cc|abbr=on}} injectors, up from {{Convert|120|cc|abbr=on}} in the early model engine. With the larger injectors, the HPOP capability was increased by utilizing a 17° swash plate angle to meet the requirements of the new, higher flowing injectors.

The engine used forged [[connecting rod]]s until powdered metal rods were introduced for early 2002 models. Serial numbers can be seen with the aid of a [[borescope]] to confirm the changeover between the 2001 and 2002 model years. These new connecting rods sufficed in an unmodified engine, but would become a potentially catastrophic failure point if aftermarket tuning pushed the engine above {{Convert|450|hp|0|abbr=on}}.  Early models did not use any form of exhaust aftertreatment, such as a [[catalytic converter]], as emissions were not enforced on diesel motors; however, by mid-year 2002, Ford began installing catalytic converters as part of the OEM exhaust as part of the Tier 1–3 standards.<ref>{{cite web |title=Proof my 2002 7.3 did not have a catalytic converter. |url=https://www.powerstroke.org/threads/proof-my-2002-7-3-did-not-have-a-catalytic-converter.148432/ |access-date=3 May 2021}}</ref><ref>{{Cite web|title=Diesel emission standards|url=https://dieselnet.com/standards/us/nonroad.php#tier3}}</ref>

===Common issues===
{{unsourced|section|date=October 2024}}
Despite being regarded as one of the most reliable diesel engines ever put in a light-duty truck,<ref name="9ways">{{cite web |last1=McGlothlin |first1=Mike |title=9 Reasons why the 7.3L was the most reliable power stroke |url=https://www.drivingline.com/articles/9-reasons-why-the-73l-was-the-most-reliable-power-stroke/ |website=DrivingLine |access-date=3 May 2021}}[[dead link]]</ref><ref name="10best">{{cite web |last1=Kennedy |first1=David |title=In the Company of Greatness - 10 Best Diesel Engines |url=http://www.trucktrend.com/features/0607-dp-10-best-used-diesel-engines/ |website=TruckTrend |date=26 July 2006 |access-date=3 May 2021 |ref=5th on the list}}</ref> the engine had its own issues. A common failure point was the camshaft position sensor (CPS). The failure of this sensor would cause a no-start condition or a stall while running. The easiest way to diagnose a failed CPS is through movement of the tachometer when cranking. If the tachometer does not move, the CPS is most likely bad. The fuel filter/water separator also tends to be a minor failure point across the trucks. The aluminum filter housing can crack, causing fuel leaks. The heating element contained in the filter housing also can short out, blowing a fuse and causing a no start condition. The turbocharger up-pipes are a large failure point, with the pipes leaking from many different points but mainly from the joints. Leaking of the up-pipes causes the engine to lose boost and cause exhaust gas temperatures to increase. The EBPV exhaust back-pressure valve (EBPV) was also prone to failure; it could close when cold and get stuck on causing a jet engine like noise coming from the exhaust.

Most of the issues that came out of these motors were due to poor electrical connections. The UVCH (under valve cover harness) was prone to losing contact with either glow plugs or injectors which caused rough starts or a misfire depending on the year. 1994–1997 engines have two connectors going into each bank, whereas 1999–2003 engines had one connector going into each bank; troubleshooting the harness was easier for the 1994–1997 engines.

The 7.3&nbsp;L DI Power Stroke was in production until the first quarter of model year 2003, when it was replaced by the 6.0&nbsp;L. Nearly 2 million 7.3&nbsp;L DI Power Stroke engines were produced in International's Indianapolis plant.<ref>[http://www.dieselpowermag.com/tech/ford/0810dp_ford_power_stroke_diesel/viewall.html Ford's Power Stroke Diesel History] {{Webarchive|url=https://web.archive.org/web/20120825005419/http://www.dieselpowermag.com/tech/ford/0810dp_ford_power_stroke_diesel/viewall.html |date=2012-08-25 }} Power Stroke Spotters' Guide</ref>

The 7.3&nbsp;L DI Power Stroke engine is commonly referred to as one of the best engines that International produced.<ref name="9ways" /><ref name="10best" />