Amigo/Rodeo Sport/Rodeo FAQ's
Where I post answers I find to those oddball questions.
(Note:  RS = Rodeo Sport.  Term Amigo is used pretty liberally to cover both.)


Isuzu History
  - Names in other countries
  - Model History
  - Business Notes/ Company History
  - Parts History Info
  - Known Issues
Vehicle:  Modification Questions
Vehicle:  Technical Questions

Towing  Accessories & Info

How EPA calculates mileage

In other countries, the 2-door, soft-top version of the Rodeo (and the Rodeo itself) goes by other names:
• USA:  Amigo, or Rodeo Sport
• England:  Vauxhall Frontera Sport  (Rodeo = Frontera or Honda Jazz)
• Europe (minus England):  Opel  Frontera Sport  (Rodeo = Frontera or Honda Jazz)
• Deutschland (Germany) = Opel Frontera Sport (Rodeo = Frontera)
• Japan / New Zealand:  Mu (for Mysterious Utility) where the Rodeo is called the Wizard.
• Australia:  Holden Frontera Sport  (Rodeo = Holden Frontera).  The name Rodeo there refers to a pickup truck.
• Let me know any more!

Model History  (I am responsible for all errers...correct me if I'm wrong)
Some year to year model changes comes from   Research vehicle, view vehicle history.

Business Notes / Company History

Most of this comes from:, some from AutoNews and the Isuzu Car Site.

1916 Tokyo Ishikawajima Shipbuilding and Engineering Co., Ltd. and Tokyo Gas and Electric Industrial Co. initiated plans to build automobiles
1919 March--Tokyo Gas and Electric Industrial Co. produced its T.G.E. truck under the auspices of the Military Vehicle Support Act. 
1922 Dec--Tokyo Ishikawajima Ship Building and Engineering completed first domestically produced Wolseley, a model A-9. 
1934 The truck manufactured up to Ministry of Trade and Industry standards was named "Isuzu."
1949 July--Company name altered to "Isuzu Motors Limited" with capital increased to 150 million yen. 
1966 April--Established Isuzu Motors Co., (Thailand) Ltd. 
1971 July Signed capital agreement with General Motors Corporation (GM).  General Motors Corporation buys 32.4% of Isuzu and subcontracts them to make Chevy Luv pickup trucks.
1974 Oct--Unveiled the Gemini, the first automobile produced in cooperation with GM. 
1975 Jun Established Isuzu Motors America, Inc. 
1981 Created USA sales network.  Sep: Introduced the compact four-wheel drive vehicle UBS Rodeo Bighorn. Also, against the direct protest of General Motors, Isuzu puts the Piazza and Impulse into production, embarrassing GM because the newly redesigned Camaro and Trans Am aren't as sporty as the Giugiaro designed sports coupe. Popular Isuzu opinion is this is when GM begins undercutting Isuzu to get even.
1983 March--Aska took the first place in the RAC Rally held in England.
1984 GM begins reselling rebadged Isuzu Geminis under the Spectrum name, but, as a condition of the arrangement, restricts Isuzu's rights to advertise their own cars in the US and European markets and imposes quotas on the number of vehicles Isuzu can sell. This effectively destroys any chance for Isuzu to build brand consciousness, brand loyalty, and a reputation as a car builder, in all markets outside Japan.
1986127,630Peak vehicle sales.
1987 Sep--Isuzu-General Motors Australia Ltd. (IGM) was established.  Vehicles in Australia sold under "Holden Motors" brand name.
1989 • GM begins reselling rebadged Isuzu Gemini Coupes under the Geo Storm name. This vehicle outsells GM's own domestically produced Cavalier, Sunbird, Corsica, and Beretta models--combined.  This causes embarrassment for GM.
• April--Isuzu's production of medium- and heavy-duty trucks (over GVM 6.1 tons) for fiscal 1988 was rated No.1 in the world.
• May--A new type of recreational vehicle, the Mu, was introduced in Japan and the U.S.A. (Amigo)
• Oct--Opening ceremony held for Subaru-Isuzu Automotive Inc. (SIA).
1991108,429• Opened assembly plant with Subaru.  New ad agency: Goodby, Silverstein & Partners in San Francisco.
• Jan--Rodeo was introduced in the U.S. market.
• Dec--Full model change of the Trooper
1993 • Isuzu stopped selling passenger cars.  Jan--The UCS (Mu / Amigo) took prototype diesel class victory in the Paris-Dakar Rally.
1994 • GM discontinues their Storm model, eliminating close to 95% of Isuzu sales of cars leaving Isuzu with weak name recognition and little hope of recovering from this financial blow. This combines with the collapse of the Japanese economy after Isuzu went up market to more luxurious and more expensive models with their 1990-93 redesign of their cars.  Isuzu decides to discontinue car sales.  Isuzu constructs a shrine to the much missed Gemini car in their Fujisawa plant.
Jan--Trooper won in the Marathon Class and the Mixed Class and finished second in the non-modified stock-standard class at the 1994 Paris-Dakar-Paris rally. Sales of Honda Passport (the U.S.-built Rodeo) started in the U.S. market
199693,888• Aug--Trooper (Holden Jackaroo) won the 1996 Australian Safari
1997 • Mar--VehiCROSS, all round sport-utility vehicle was introduced in Japan.
• May--The Kingfisher 33, an Isuzu fishing boat, started its sales in Japan.
1998 • Isuzu attempts to purchase then financially troubled Nissan Motor Company in order to acquire a name and a company to build passenger cars under.
• June--Wizard (Rodeo) and Mu (Amigo) were completely remodeled
1999 • March--General Motors raised its equity share in Isuzu to 49.0 percent through a third party allocation.  This is a controlling interest, but due to Japanese laws restricting foreign ownership of Japanese corporations and Japanese labor laws which strictly follow seniority, GM is unable to appoint an American to head Isuzu and must continue to deal with Isuzu management's continued resistance to GM domination.
• April--VehiCROSS debuted in the U.S. market.
2000 Wayne Sanaghan thinks this is when the Amigo became the Rodeo Sport.  July--Diesel engine production started at DMAX, Ltd. in the U.S.A.
200182,380Jan--Duramax 6600 diesel was selected as one of the 10 best engines by Ward's Communications in the U.S.A.  Isuzu Motors total sales of $10.8 billion, net loss of $2.9 million.  (Original numbers in yen.  Sales: 1.3 trillion yen.  Net loss: 350 billion.  Using  $1 = 120.5 yen)
Isuzu lays off 25% of their international work force due to financial losses and ailing sales.
200252,992• Jan--Duramax 6600 was selected again as one of the 10 best engines by Ward's Communications in the U.S.A.
• Dec--Fuji Heavy Industries Ltd. and Isuzu executed signatures on agreements to dissolve joint venture at Subaru Isuzu Automotive (SIA) in the U.S.A. under terms of the deal, Fuji will continue to produce about 30,000 vehicles a year for Isuzu to sell in the United States.  Isuzu moves their manufacturing to Thailand.  This completely withdraws their joint SUV venture with GM, with the exception of the GM Trailblazer which will be rebadged as the Isuzu Ascender.
• General Motors dropped its stake in Isuzu Motors Ltd. from 49% to 12% (or Isuzu bought back 38% in a debt restructuring deal, depending on your perspective).  At the same time, GME moves from 49% to 60% stake in a joint venture to produce DuraMax diesel engines in the United States and Europe.  
• New ad agency: Malone Advertising, a small retail specialist in Akron, Ohio, with just $80 million in annual billings.  Joe Isuzu goes away again.  Thanks to the old idiots for the hideously bad "Amigo! Amigo!" commercial.
• Expects sales of $8.3 billion, net loss of $10.8 million.   (Original numbers in yen.  Sales: 1.0 trillion yen.  Net loss: 1.3 billion.  Using  $1 = 120.5 yen)
200330,328 • Jan--General Motors decreased its equity share in Isuzu to 12.0 percent based on Isuzu's new three-year business plan. Isuzu and General Motors established a new joint venture company called GMI Diesel Engineering Ltd. (GMIDEL) for powertrain systems. 
• Aug--Return to profitability.
• Isuzu finds itself in the enviable position of being one of only three commercial truck producers in Japan who is selling diesel trucks that comply with the new, strict emissions laws for the Tokyo metropolitan area, which require particle scrubbers for exhaust. The law outlaws the use of trucks without these devices in and around the four prefectures surrounding Tokyo, and as no aftermarket retrofit is available, truck operators are required to buy new trucks. Mazda, unable to develop a commercial truck that complies with the new emissions laws, subcontracts all it's commercial truck production to Isuzu. Isuzu leads commercial truck sales in Japan and shows a profit for the first half of 2003 for the first time in decades. Isuzu's stock showed a 300% increase in value.  A similar diesel law is coming to the USA in 2007.
• Isuzu releases rendered images of what they call "a sports coupe" which is described to be in the vane of such noted Isuzu cars as the Bellett 1600GTR and the Giugiaro designed 117 Coupe.  Isuzu appears back on track to build cars.
2004 • March:  First Turnaround Month!  Isuzu stock passes 235 Yen per share, a 470% increase since Spring 2003.  Isuzu sold 4,057 SUVs (mostly Rodeo's), 23 percent more than a year ago, on higher demand for the Rodeo model. Market share for Isuzu rose to 0.3 percent from 0.2 percent.
• Isuzu continues working towards severing all ties (and buying back all stock) from GM by 2007.  The Rodeo and Axiom (now made by Subaru at the Lafayette, Indiana plant) will be discontinued at or shortly after the end of the 2004 model year. There will be no serious effort to market the GM made Ascender through the 2005 and 2006 model years, after which Isuzu's contract to sell that vehicle will end. Isuzu plans to introduce at least two completely new models in late 2006, totally designed and manufactured by Isuzu.
200427,188The Chicken Tax was looking to fall with a free trade agreement with Thailand, the main source of Isuzu manufacturing.  Unfortunately, the agreement didn't go through.
200512,177Isuzu dealers will get a version of the GMC Canyon pickup beginning in July. The 2006 Isuzu pickup will come in two versions, a 4x2 extended cab with a 2.8-liter I4 engine and a 4x4 four-door cab with a 3.5-liter I5 (Not the Direct Injection v-6). Isuzu also said that U.S. dealers will not get a compact SUV from Thailand that had been expected for the 2007 model year. Isuzu is not bringing the SUV from Thailand because it will not be profitable, said Terry Maloney, president of Isuzu Motors America Inc. Maloney also told dealers that Isuzu will develop a new diesel engine in the 3-liter class that will be sold in the United States. No date has been set for the diesel. 
20068,614Mitsubishi will now become the largest single shareholder in Isuzu with 9.7% of the stock, followed by trading house Itochu Corp. with 7.2% and Toyota with 5.9%. GM sold all of its stock in Isuzu back in April, which amounted to 7.9%.

Other Model History Stuff (Parts Information):           

Known Issues (Rodeo / Amigo / Rodeo Sport):  You should always check the NHTSA for recalls.  Don't just search "Vehicle," search "Equipment" for the other parts like Radios, tow packages, etc.  Some of the dangerous ones are listed below, but NHTSA has the full list.  Many of the 98+ Amigo/Rodeo Sport problems are duplicated in the Rodeo.  Minor problems that aren't recalls yet can be found at on Tech Service Bulletins.  You can view the title for free and get an idea if other people are having the problem.  Some info here is from NHSTA, some from Tech service bulletins, some from OutdoorWire Isuzu board, and some from Auto Consumer Guide.

Vehicle--Modification FAQ and Info



How the EPA calculates mileage
Ever wonder why you don't get the mileage listed on the sticker? Here's how it's tested, from the EPA website / documents. Note that I did the best I could with the long, dry, and strangely repeating government regulation.  (Note: simplified.  See link for full info and formulas).  NOTE:  This is prior to the 2008 change that slightly reduced mileage by adding in higher speeds, faster acceleration, and more extreme temperature..

The EPA does not test most vehicles. Automakers do, using EPA standards, and tell the government the results. It's not even always necessary to conduct tests, according to federal regulations: "In lieu of submitting actual data from a test vehicle, a manufacturer may provide fuel-economy values derived from an analytical" calculation approved by the feds. The EPA randomly tests vehicles to keep car companies honest but gets to only 15% of new vehicles each year. 
Both Tests:   Driver (or passengers) have no weight.  Never travel over 60 mph.  Lights off (loads down the alternator), A/C off, windows up for minimum drag and power loss.  No hard acceleration.  Drive in warm weather (the testing room is 75 degF).  Engine is already warmed up.  All driving on flat roads, with no congestion.  Subtract out un-burnt gas that goes through the system.

City Mileage: The city test is approximately 11 miles long and is a stop and go trip with an average speed of about 20 miles per hour (mph). The trip lasts 31 minutes and has 23 stops. About 18 percent of the time is spent idling (as in waiting for traffic lights). A short freeway driving segment is included in the test. The engine is initially started after being parked overnight. Vehicle operation is on a chassis dynamometer through a specified driving cycle.

Highway Mileage: The highway fuel economy test is designated to simulate non-metropolitan driving with an average speed of 48.6 mph and a maximum speed of 60 mph. The cycle is 10.2 miles long with 0.2 stops per mile and consists of warmed up vehicle operation on a chassis dynamometer through a specified driving cycle.

To calculate MPG: (d) For gasoline-fueled automobiles, calculate the fuel economy in miles per gallon of gasoline by dividing 2421 by the sum of burnt gas ejected from tailpipe.

To summarize, the vehicles are run on a dynometer where wind is "factored in." They also don't account for a family loading it down with body weight and gear.  Typical city stops are every 90 seconds where you gently accelerate to 40, then slow down to 0, driving like you have an egg between your foot and the pedals.

For highway mileage, you start from zero, then drive at an average 48.6 mph, max 60 mph. Stop once and repeat.   Who do you know that drives on the highway at 55 mph?  Here in Texas, I'd get run over. I-10 in west Texas at night looks a lot like Mad Max.

Force of Air Drag = (1/2)*(Drag Coeff)*(air density)*(cross sectional area)*(velocity^2)
You can't affect any of them except velocity...and it shoots up as a squared function.  Gas consumption at 75 mph (the speed limit in New Mexico and Arizona) is much greater than consumption at 55 mph. (I read once the best thing to do when low on gas is travel at 45 mph for your best mileage in a high gear). 

We might have a case to go back to the dealer and demand a refund on all unburned gas caused by the inefficiencies of the engine that prevented us from getting the documented mileage. For a 93 Isuzu Amigo 2.6L the EPA has the following data:  (City/Hwy/Combined)
ISUZU AMIGO 4WD Estimate: 18 / 21/ 19 Unadjusted: 20 / 27 / 22
I never did figure out what "unadjusted" meant and got tired of trying to find it.

Hybrid Car Owners Complain of Faulty Mileage Estimates  Csaba Csere, editor-in-chief of Car and Driver Magazine, comments that car companies have to report the mileage reported by the EPA test. Sll vehicles perform below their EPA mileage ratings in real-world conditions, but hybrids more so. When the law was put in place, government never though that car companies would want to report a LOWER gas mileage.
Additional info from USA Today (2004 article)