I have a '92 E-350 Box truck with the 5.8. I've never had any trouble since I've owned her. She's relatively low mile for the year (150,000) and I've owned it about a year and a half now. I use it daily for my flooring company and I took a week off for vacation. I returned to work and it ran fine on my way to pick up material. I loaded up and started it and it started surging idle. If I hit the gas it ran fine. It also smells rich and went through 1/4 tank on a 40 mile trip which is way off from normal. Initially I thought vacuum leak. I have checked everything I can possibly check and can't find or hear any vacuum. I then read on how to pull EEC codes so I did that and got this.
KOEO 328 current
172 in memory
KOER 126
172
173
328
Definitions:
172- system lean
173- system rich
126- manifold absolute pressure/barometric pressure low.
328-EGR position sensor valve signal low

So I have the codes and definition but my question is can all of this be going back to one code? What should I check first?

 

Too old bro. Most of us here don't have experience with that old system.

I'm sure there's a section somewhere on these forums that can help. Maybe that same year of full size trucks or something.

 

Not true! There are a lot of us old timers here running the old one's

I have a '92 E350 5.8 cube van, and it replaced the '94 E350 5.8 cube van that I used for 11 years.

Done a lot of wrenching on both of them.

First off........here's a Link for the codes. Might be a little better than what you deciphered?

Did you pull the codes from the CEL light, or hook up a OBD I scanner??

From what you wrote, the ECU might have had a brain fart, and when it acts up like that, you should have turn if off, waited a couple minutes, and re-started, to see if it ran better.

One of the sensors could have been giving the ECU a bad signal or the EGR might have stuck closed causing your problem.

Another quick check is to pull the ECU out, open the case and inspect the circuit board, there are 2 capacitors on the board, if they are leaking green junk, that would cause a lot of problems.

Other wise, it checking all the senors one at a time, and here's a link for that.

Checking all the vacuums lines was a good first step, replacing them 20+ year old lines is even better, but generally, a vacuum leak will give you a high idle, that's the tail tell sign of a vacuum leak.

One question, did it run as you wrote from that time on, or is it running the same as it did before the problem?

The only other thing is you took a weeks vacation, and didn't take the daily ride with you, and she got jealous??

 

Yeah there is a pleasingly good knowledge base for the pre-97 E-Series, those when the Modular Motor series engines became just about the only engines available. For my money Wildman is one with a quick reply on where to start trouble shooting issues for those motors.

Engines from that same era are also very well supported in the forums dedicated to them----we often overlook or forget those exist here on FTE. This might be helpful: https://www.ford-trucks.com/forums/forum54/

Wildman is there a link or any photos of those leaking capacitors available? IIRC there is or was a whole thread on replacing them, how to visually inspect them etc etc. If so such info would make a great addition to the Tech Folder here.

As for the jealous daily driver left on while on vacation---seems improbable but damned if it just don't seem true too often huh?

 

I never could read those flash codes....!!!


AZone or Oreilys has code reader for $20...


I would look at a possible failed fuel pressure regulator and check fuel rail
pressure with a gauge....

 

I don't know off hand were the threads were, couple of months ago it was here on E-series, So a quick look found this thread = https://www.ford-trucks.com/forums/1...or-source.html = But post #2 is how I would reply, with the same option.

Mainly due to the age of the vehicle, and how many miles of hitting potholes, and yes, an expensive $100 part, But, having a re-man unit that has been checked over by specialized company and flashed to the vehicles drive train, would warrant a replacement re-man unit.

Like cleaning an IAC, it might work, for a short time, But replacement is a time saver on R&R itself.

kynnhoj wrote - "AZone or Oreilys has code reader for $20..."

Yes, for OBD II systems, you can find readers all over for OBD II systems, and the parts store can read OBD II, but not our older OBD I, ECC systems.

I bought my code scanner 10 years ago, for $99, and it reads OBD I, OBD II and CAM, and it was worth the money over the years I used it, and everyone else that "borrowed" it, for both systems.

So.......if The Floor Guy stops back in here.........another thought I had re-reading his OP is to check the plug wires, while he was on vacation, one of them fuzzily critters might have tried to make a meal on the wires, and what he is experiencing might actually be a 'mis-fire' causing the problems.

If your going to throw parts at it, might as well start with the cheapest part first.

 

Thanks for all the replies and yes I'm still here. Been having to catch up on work. I pulled the engine box off last weekend and checked all the plug wires and all which are only about 6 months old and all looks well. For the hell of it I disconnected the battery and let it sit a few hours. Hooked her back up and went to work. It ran great on my way to my shop. Idled great when I got there. I shut it off went inside came back out to move it to load up and it still ran great. Shut it off and loaded my job. Started it back up and sure enough it started to do it again. As soon as I can I was going to pull the IAC off and clean it just to see if it helped as I have a 99 Expedition that I did that to and it cleared up a rough idle. I'd hate to just start throwing part$ at it only to not find the problem.

 

Okay updates. I cleaned the IAC and no change. Still surges at idle and guzzling gas. A couple things I noticed today. While surging at idle the volt gauge goes crazy. I'm assuming it is dropping as the truck nearly cuts off then jumps way up when it surges?? Probably not causing my problem but happening because of the problem??? Also when I turn the engine off I'm getting a buzzing/hissing sound for probably about 10 seconds after I turn the key off. It slowly gets quieter and fades away. I located the problem to be one of 2 sensors that are bolted to a bracket on the rear drivers side of the motor right next to the coil. I can't quite pinpoint which one but can tell that's where it is. They look like some sort of vacuum switches and maybe one is leaking? But I've heard that since I've had the truck so not sure it'll fix my problem but I'm sure I need to replace it anyways I just don't know what it is. Thanks again for all the input.

 

Double post deleted

 

I think you got a double post there.......
Also.......if you could brake up your one big paragraph, it's easier to read (and answer)

The more info you provide, the better it is for us to help you find the problem

Your disconnecting the battery, you only need to have it disconnected for 20 minutes, and that will clear the codes in the ECU.

With the codes cleared, or even with a "cold" start, the ECU operates in "open loop" until the engine gets to operating temperature, approx 200 degrees, then the ECU operates in "closed loop" reading all the sensors and what not, and makes finial trim adjustments to fuel/air/timing for opt running conditions.

As you wrote, with the codes cleared, and a cold engine, the ECU is operating in open loop, once you make a few stops, and get underway, the engine is now operating under closed loop, the stopping and re-starting is on the ECU's closed loop, and it begins to not run as it should......sound correct??

Your next trip out, let it idle after you first start it in the morning, don't shut it down, and see what the results are.

You wrote, "Still surges at idle and smelling like gas."
A high idle, and gas smell is a tell sign of a vacuum leak, fresh air is getting sucked in the intake, by-passing the senors, and the ECU is over compensating by letting more gas thru the injectors to keep it running.
Now we need to figure out which sensor went hay-wire.

You wrote, about the 2 senors on the left side, those sensors are 'EGR Valve Control Solenoid / Motor' There controlled from the EGR valve.
It's normal for them to "buzz" after shut down.

Here's a Link on the operation of the EGR valve.

Yes, I'm going to post links, and you should read them, your there, in front of the problem, I'm here, and in some cases, solved my own problems, by reading (and bookmarking links) that solved my problems before.

Why the link to the EGR valve, cause that's where I think you need to start.
The EGR valve could be causing your problems, as you read, once it hits operating temp, the ECU is in closed loop, and the EGR is Not doing it's job.
Cleaning the EGR is do-able, but replacing the DPFE might be needed.

Also, check the EGR tube from the front of the exhaust manifold, that can rot out and leak, causing problems.

There is also a vacuum line to the DPFE that might have came off, or the hard plastic line might be broken. The line runs from the intake manifold "tree" over to the right bank, up/over to the front connected to the DPFE.
Check that line first. If broke, it's not closing the DPFE, and drawing in air to the intake, if broke, it can be repaired with slipping 5/32" vacuum line over the break, and that will seal it up.

Also, the volt gauge will "bounce" around as the engine is choking out, the belt is not slipping, but the RPM's are dropping, and causing the alternator to not charge, causing the gauge to bounce, or drop down, and jump back up.

Check out the above first, as I've typed enough this morning........
See what you found, and report back here.
If that solves the problem, we're done, for now. If not, we'll look into the next solution.

I've been were you are now, just last year, had many problems with my '92 5.8, try many solutions, some worked, others did not, I got the van with 104K on the clock, at 126K I found many other problems, wasted alot of time trying to solve problems, and the end result was a new re-man engine, now my van runs like a top. I don't think you need to go that far, but it happens.
Former owners could have beat the engine so bad, I ended up with the problems, but, I got the van for a good price, and had the budget to invest into it. Plus, I looked around for over 2 years for a replacement, and seen cubes priced 3x's what they were worth, and snagged this one for the price.

I got to get to my day job, hanging doors and finish hardware, I had to wait for the floor guys to get done, to finish my work, and yes, I always get along with you floor guys

 

Wow. Thanks for the input. Sorry about the double post. I started a thread on the issue in the truck section as well and thought I was there.

Anyways (in a new paragraph) I will start checking on what you suggested and report back. I appreciate the links and yes I do read them all thoroughly.

As for the "gas guzzling" the truck doesn't idle high at all. It just surges from I'd guess 600-1500 RPMs.

 

Didn't have a chance to mess with the truck today but this morning I was going to do as suggested and not shut it off while at my shop however as soon as I started it this morning cold it started surging.

It's just an annoying problem and now I'm working day and night jobs so tinkering with it has been impossible. Hopefully I can find some time this weekend to try some stuff.

 

AZone has Innova 3145 OBD1 reader for $30.... (inflation, I guess or "vintage" ?!!!)

 

Probability more like "vintage" ........

The Floor Guy = One other thing I thought of ......while your in there (under the dog house) Check the fuel regulator, it's on the back left side of the fuel rail, just above the 2 fuel line, Pull the vacuum line off with the Key ON, and see if any fuel is coming out of the top (vacuum line) of it, it's worth checking for the surging problem that you experiencing.