Was this the changeover year from the Panther platform to the rounder last generation non-LTD Crown Vics with the introduction of the 4.6 modular engine? Often, with such a major redesign manufacturers will start production quite early as with the Mustang as a "64 1/2" or the new Super Duties in 1998 as 1999 models.

dn.

 

1991 was the last year for the "Box whales"...
(351w's were still carbed, 302's were already CFI/SEFI by this time)


1992 Was the first year of the MAF/OBD-I "Aero" Crown Vics...
This particular bodystyle lasted until 1994, when some minor styling was added...(Taillights, etc....Although similar, they're definantly different...1995-1997 had the redesigned taillights, etc...)

-The engines had different heads, between 92-97, and the 98-03, and the 04+ models...

1998 was the first year for the style of Crown Vic, that lasted till August of 2011....




And yes, any redesigns, upgrades, etc...Is USUALLY made, from August/September of the PREVIOUS year.....

EI-

8 or 9/1991, the 9th gen trucks were starting production for january of 1992, etc......You get the idea....

 

A couple corrections here, the cutoff weight was 8500lbs and all trucks and engines below that went OBD-2 MAF in 1996 for all states and provinces, that means all 1/2 tons and LD F250s. But since the 7.5 was a rare find in a LD F250s and not available in the 1/2 ton you generally only see the 3 smaller engines with this configuration. However MAF 460s in both OBD-1 and OBD-2 formats do exist thanks to California's tighter emissions restrictions, they got MAF a year earlier than everybody else(1994) and on some HD trucks that never saw it elsewhere.

 

Which is why I never add Cali-specific stuff into my posts...unless I make specific note...Which I did a few posts back, post #11 actually.......

 

My 1996 and 1997 Ford CDs show the OBD-I break point for the 7.5L trucks is >8500 lbs. for 49 state and >14k for California. Below 14K for the Cali. trucks show up as OBD-II.

1996 OBD-I


1996 OBD-II CA trucks


1997 OBD-I


1997 OBD-II


Have we found Ford Service Manuals wrong before? Yes. I have several different sets, they all have the same info on this topic.

I did mention the light duty F250 was OBD-II.Can't say I have ever run across one with a 7.5L engine. I am sure they exist, there seems to always be exceptions to the "rule".

I too was of the mindset there were OBD-I MAF 7.5L trucks out there. So far I cannot find documented proof. I have scoured the VECI labels and Calibration Codes at Motorcraftservice.com to come up with some empirical values. So far no luck.

 

I do purposely mention them, because they are out there.

 

Again...If I mention it, it's specific...