Geo Storm or Isuzu impulse

What really is, a GEO STORM (rare old car) ;?

The car is really an Isuzu Impulse minus some of that car’s more expensive features. A detuned Impulse. Isuzu killed it, after 3+ years of production. 1990 to 93′

The car had 1 of 3 Isuzu engines. (In the USA? open hood , look up see EPA sticker?, bingo it clearly states which engine is here.) Just counting cams helps here.
The 3 engine EFI systems can be different, same with all cars, years, engines and evolution of same, so what do we have here
To me, they are all the same, but just 2 systems, Speed Density and Air Density (MAP based or MAF, respectively ) and work totally contra to the other. (a key fact, that all technicians, learn first)
The engines have a Cam timing belt. That is rated for 60,000 miles, only. Do not ignore any DOHC belt or be sorry later.

  • 1.6 L SOHC4XE1 I4 (all Isuzu engines codes) MAP based. (only this motor is free running ,Cam belt snaps, you are OK)
  • 1.6 L DOHC4XE1 I4 (wow, same name but new 16v head) MAP based still. See belt rule below.
  • 1.8 L DOHC4XF1 I4 (both DOHC engines ARE Inteference type, so if belt snaps?, say bye bye to the engine head valves (now bent) or worse)

Finding parts and books on this car can be hard. (use EBAY for used FSM books, is the best plan) Or online…
OEM parts and nice drawings here.

Storm facts 1:

Storm facts 2:

Speed Density EFI rule to learn:

  1. All induction plenum air leaks (aka;vacuum leaks) cause, a too fast idle speed and full power, no bogging or lean outs.
  2. Lean outs are caused by , low fuel pressure, or clogged injectors, or last a bad MAP, (or is just dirty vacuum paths or its vacuum hose/ports dirty)
  3. Flooding is , caused by (skipping tuneups) or Too high fuel presssure, leaking injectors. or MAP PRESSURE LOW (LOW VACUUM)

Geo’s Died 1997 and changed to Chevorlet names, for same cars. like Chevy Trackers until 2005 (and still sells parts at GM) See the crazy history here.
Real Isuzu USA car sales, died in the in January 31, 2009, but sells parts.
Storms and Spectrums died, in 1992/93

OBD1 , secrets (no scan tools)
The Diagnostic jumper (flash code jumpers) are here.

Buying parts for a STORM (or any ISUZU car).
GM (Geo) doesn’t have most of the parts now. (“discontinued”, is the operative word, on most parts , even crank bolts missing..)
Isuzu cars and light trucks left (bugged out) NO SALES, in the USA in 2009 (leaving this pathetic slim pickings place.)
Never buy or own any GEO cars. IMO (with the exception of the Prism (Toyota Corolla it is) and has parts )
Finding key part to keep a GEO running, takes luck, skills, and hard work, and down time)
Some OE parts are still sold but takes like 10 days or more from some far away warehouse. 2 weeks deliver is common. Down time.
The Geo Tracker parts are hard to get too. see why here.

If you have the GEO Prism, go to Toyota with your parts needs. (carry them in for show and tell ) They were made side by side same day at Toyota !
To understand the GM/Isuzu relationship read this.

Best is find a GM dealer that can fix your car. Some can. Some take months to do it, waiting for parts.
Same with Saturn’s or your fathers Oldsmobile? , Pontiac and Hummer, and Saab.

Best place for asking questions is FixKick forum.

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