This is my first post and you'll see why if you read all of this. Let’s call this my Father’s Day gift to all you mothertruckers out there.

My truck:
1996 F-150 XLT Off-Road 5.8L 4x4 e4od transmission (that’s 4 oh dee not forty, it can be hard to tell when in capitals E4OD)

Keywords:
fuel filter
spark plugs
vehicle speed sensor (VSS)/rear differential ABS sensor (RABS)
3rd brake light

If you typed any of those in a search engine and found this thread, please do yourself a favor; read this and learn from me. It may apply and it may not but the ones it does apply to are in for a shock. Spoiler alert!

First a little background:
I'm a framer/carpenter so I always say if it ain't made outta wood, I can't fix it. This is nearly true (see "bolts" below).

At the end of last summer my water pump went. A friend of a friend tried helping pull it and we managed to break 3 bolts off in the block. So into the shop she went (yes, ouch). Afterwards the truck sat more or less through the fall and winter. When I went to drive it 25 miles to my sister's about a month ago it ran very rough. Also I'd been having intermittent hard shifts and the yellow, overdrive "off" light on the end of the gear shift would flash. If I restarted the engine it would usually go away. I kinda knew it was electrical in nature and not mechanical because it wasn't constant. Or at least I hoped. On the ride up the speedometer pegged itself at the top end and the odometer went out for about five minutes. This had only happened once before.

My brother-in-law Dave has a '48 Dodge Custom which he's learned to do some work on. So he knows enough to be dangerous. Someday I may as well.

First we tackled the fuel filter to address her running rough. We figured the gas may have gone bad sitting for 6-8 months. If I can tell you anything about that it's don't give up. It’s a bear but work it, work it, work it. This is also where the “Off-Road” package came into play. I have a heavy skid plate under the truck to protect the gas tanks. So even less room to get to the rear fitting. For the front fitting I grabbed it (gently) with pliers for some extra grip-tion and it finally came apart. The little clips inside the fuel line fittings may not survive the removal if yours has been in there as long as mine (15-20 years minimum) but they are replaceable. A very small flat head screwdriver (such as from a mini screwdriver kit) and needle-nose pliers are a big help with them. I used the 5/16” clip and just made sure it’s fully seated inside the lip of the fuel line fitting. The screwdriver is perfect for this and I put mine in by hand. I’ve seen others say to wrap it around the new fuel filter when installing it. I wanted to see that it was in before I got to that step.

Took a test drive but she still ran rough. Dave’s next suggestion was spark plugs. As well we searched the weird-wide web which learnt me to look at the transmission speed sensor for the hard shifts. I watched a video from a parts dealer not a shade tree mechanic which I figured by definition would need to be accurate. Ordered the parts and found I don’t even have the transmission sensor I saw in the video. That’s a return. I wish they wouldn’t assume every F-150 was identical and tell you what engine they’re working on. Even so look under the truck first next time, Dummy. The worn plugs came out gapped about 0.060 when they should be 0.042-0.046 according to the under-hood sticker. If you haven’t done them the worst part was actually pulling the damn plug wires. Yes the passenger side doesn’t have a ton of room for the ratchet in the back but it’s workable. And on the driver’s side one plug wire needs to be pulled with pliers because the oil dipstick bracket is bolted too close to pull by hand. But man did they make a difference. On the test drive I hit the on-ramp for the highway and just floored it. I didn’t let up until I hit 70 and she didn’t hesitate. Best she’s ever run.

Still had some shifting issues and when we got back my sister had to run my niece to her field hockey game and get their other car from where their son was working. I volunteered to help and got in the truck and she wouldn’t start. They left to handle it on their own and then it occurred to me to knock on the starter with a hammer. I did and she started right up. So a new starter was in her future. I also found info (maybe here, I can’t remember) about the vehicle speed sensor (VSS) in the top of the rear differential (pumpkin). This is where things get confusing. I learned from a forum (here?) to get a good starter from Napa and avoid the Chinese ones. I wanted to order the VSS as well but there’s 3 different, identical sensors that come up on the website. So I called and the guy told me the ABS sensor is what I wanted.

So I changed the starter. I had 3 wires on mine, the heavy red positive, the small, spade-fitting ignition wire and a little wire to nowhere. Literally it was a 6” long wire with an eyelet attached to the small bolt and ending in mid air. It may be a remnant of a remote starter. Irregardless it didn’t affect the starting so it was eliminated. No big, black ground like the video though. Apparently the V8’s don’t have a ground. Once again no details on the engine in the video but it definitely wasn’t mine.

So I button everything up, reinstall the negative battery terminal and start her up. Yay! I had already swapped out the differential sensor so I was ready for another test drive. Just getting to the highway I could already feel the bad shifts. Once I hit highway speed the speedometer was popping wildly from about 40-70. So the ABS sensor was not the fix. As I said there were 3 identical sensors so I figured maybe it wasn’t an ABS sensor but the vehicle speed sensor. Looking through one of the forums I found a bizarre thread. The guy giving advice in the thread was claiming the 3rd brake light was the issue for someone in the same slowly sinking boat. That’s nuts! Who would think of something like that!?! “Ford engineers” was his answer.

I had just got her inspected and they told me that light was out. They wouldn’t fail me but said to get it fixed. I had thrown in some Sylvania 921 bulbs on one order for just this purpose but since they can’t affect the running of the truck I hadn’t bothered to install them yet. Someone on YouTube mentioned LED 3rd brake lights can create shifting issues as well so now I had confirmation that either these guys were nuts or the “Ford engineers” were.

It was the engineers.

I changed the 3rd light and took yet another test drive and nary a problem. How’s that for a twist ending?

For the guys in the know, she was throwing a P0500 code before and now it’s a P0174. My brother-in-law has an OBDII reader even though the Dodge has no use for it. Gotta get one. I also replaced the K&N air filter and dumped a bottle of Red Line SI-1 Fuel System Cleaner in with a full tank of gas.

If nothing else I hope this was an entertaining read and you guys can have a good laugh at me. If you have any suggestions (especially about the new code) I’d be happy to hear them.

Thanks for the help I have found on this forum,
Roman

 

An update:
Well the ABS sensor/3rd brake light combo didn't do the trick. Still getting the OD "off" light flashing and bad shifts. I found a thread somewhere that the #8 and/or #18 under dash fuses may be the culprit. Bought some 15A fuses so I'll give that a try.

Maybe that same thread the person said they went to the dealer and replaced the VSS and someone replied to put the original back because new ones create more problems. I have no idea obviously but any help would be appreciated.

Roman

 

Flashing OD light means the transmission has a code and a fault
Reading the codes and checking a few pids is where I would start
You really need a scan tool like this
Or Forscan
Most basic scan tools are made for powertrain control
Your 1996 EEC5 OBD2 E4OD truck will be OBD2 and need the NGS according to the Ford service manuals
Get the powertrain and transmission codes checked any way you can and go from there (do the pinpoint tests)
Good luck
These NGS scan tools are no longer 5500 on Ebay

 

Yeah my brother-in-law Dave checked and it's throwing a P0174 code which is fuel related.

Yeah we looked up the P0174 code. Apparently "Bank 2 of the engine has a lean fuel mixture". I don't know what that means yet but I swapped out the ABS sensor I got from Napa (on their recommendation) and put the original VSS back in the differential (seen elsewhere in a forum). I changed the #18 and 8 dash fuses and took a test drive and did not experience any of the shifting issues. No lights either. I'm not going to say it's fixed yet. I guess time will tell.

I took a quick look at NGS scan tools but they seem really pricey. I'm working with a limited budget.

 

Sounds like you might have it fixed
Maybe keep searching for a NGS (took me 40 years to find a Boss 302 motor)
There are guys on Stang.net willing to sell their NGS's cheap
After about 2004-2005 the NGS is worthless
But for 84-03 Ford vehicles it is indispensable
And if trying to read E4OD trans codes on 89- 95 Fords, the NGS is the only scan tool that will do it
Maybe a few high-end snap-on scanners will read trans codes, not sure

 

Thanks for the info. I need to get a cheap scanner for now but I'll keep that in mind for down the road. And yeah, I hope it's fixed. The fuses still looked good and I tested the new ones and they were working. Maybe swapping the VSS for the ABS sensor in midstream wasn't the best way to go. Fix one thing at a time instead.

 

I just sprayed the MAF sensor with cleaner. I figure do that since I just changed the air filter and maybe dislodged some dirt. Plus it's cheaper than an oxygen sensor. One step at a time.

 

Ordered my Forscan scanner today. I won't get it for another week but I can wait.

I went to my mechanic today to pick his brain about the VSS/ABS sensor. His advice was to try another brand, sometimes they're just bad. So I went to a Federated Auto Parts and got one. Just put it in and found a rubber tube broken off that connects to a barbed fitting on the driver side of the rear axle. I was able to remove the broken stub, cut the tubing clean and replace the tube. Can you tell me what that tube is and what it does?

Also according to the girl at Advanced Auto who did a scan for me today I'm still getting the P0174 code. So it looks like a new o2 sensor. Any advice there: brand, retailer, replace one, replace both upstream, replace all three? They've been there a long time. I've had the truck for at least 15 years though I may have put less than 50,000 miles on her. She's at 177,000 now.

As always, thanks.

 

So I got my Forscan scanner yesterday and ran it. I got two codes. The P0174 I already knew but the P1500 is new to me. It still relates to the VSS though. I've included screen-grabs in case it tells someone something that I should look at first. I noticed the P0174 code doesn't mention the O2 sensor as a cause even though that and cleaning the MAF sensor are usually the first remedies mention.

 

The pinpoint tests for code P1500 are next
In the PCED