I'm new to this section of the forum as I normally hang out in the 73-79 section but I have some questions about my 96 351, my check engine light is on even after I fixed a bunch of broken vacuum lines, and there is no were to put a code reader underneath the dash, I been told it's on the fender wall on the drivers side but there's a special way you have to test it like crossing wires over or something. I've have also noticed that my speedometer bounces around once you go over 65 mph, and that sometimes the engine RPM will jump which does not happen often but does occasionally, transmission issue? It's a automatic. Any ideas?

 

No...the DLC Data Link Connector is located under dash, under steering wheel area, trapezoid shaped connector. The only DLC located on the driver fender area in engine compartment are for the RABS or 4 WABS (which illuminates ABS or brake light) or main DLC in the 7.5ltr

Speedometer is pulse read off the sensor on the rear differential. Maybe that the sensor is failing or wiring to it (usually sensor pigtail/connector) is brittle.

 

WRONG. Unless he has a MAF/California equipped truck, he will have the EEC IV connector under the hood on the drivers fender. HD Federal trucks were not required to go to OBD II in 96. Get a code reader for $25-$30 from the parts store, it makes pulling codes a breeze.

 

actually, not to prove you wrong, but i have had codes pulled from the piece on the in the engine compartment on my 92 f150. I believe its an obd1 port. and no, you dont need to jumper wires. Im pretty sure thats what i did, its been a while, and if i remember right out of oreillys auto zone and advanced auto parts, only oreillys had the obd1 scanner. so, might help to just take a look if you need to!

 

yes pre 95 1/2 fords are read in engine compartment...96 is OBDII which is under dash but blkf250 is also right in saying they weren't mandated yet until 97....

 

On light duty Federal vehicles. The F250s, 350s, and F-Superduties were not required to go to OBDII. Mine is a 97 and has the EEC connector under the hood.

 

ahhh learn something new every day, thanks for clearing that up for me!

 

Very interesting information here, thanks for the info, I may have to start hanging out more in this section of the forum and learn even more about my 96! lol

 

As for the bouncing speedo it was doing that in my 97F250 which is the old body style, and is obd1. I replaced the vss which is located on the top of the rear diff. Do yourself a favor and if it reads a fault on the vss change it with Ford part the dealers carry them in stock. I changed mine with a cheapo autozone one and it never fixed the problem. Once I got the motor craft one fixed instantly.

 

Warm up the engine and transmission then do this: Fuel Injection Technical Library » How To Run a Self-Test

Or purchase a code reader such as the Equus 3145. They usually run in the $20-35 USD range.

Run the Key On Engine Off (KOEO) tests and Continuous Memory (CM) display. Fix any issues found there before running the Key On Engine Running (KOER) tests.

Code definitions: Fuel Injection Technical Library » 3 Digit Self-test Codes 111-171