Did I just inherit a Lawn sculpture?

93 isuzu pickup, 4cyl engine. 37k odo. 5 speed manual.
Here is issue in nutshell:

My father drove this vehicle across state to give it to me. No issues until the last 15 miles. In those 15 miles, he was driving interstate speed and did not realize he was in 4th gear.

From the off ramp to my house, is 2 miles with a small incline for 1/4 mile and then level until the turn onto my street. As he topped the hill, the O2 light and the fuel light came on, it began sputtering and died as he turned onto my street, did not want to start and after he got it going, would continue to try and stall as soon as he depressed the clutch. He got it to my house and shut it off.

The next day he had me try it, and we went back down the hill and about three miles the other way with no lights on the dash, but as we topped the hill again, the check engine light, the O2 light and the fuel light all came on, and it started to sputter and would stall as soon as I depressed the clutch. It died and took some effort to start it and then I ran a stop sign so I wouldn’t stall it again until I got it home.

It probably has original spark plugs, and a 10 year old battery. The belt to the alternator seems a little loose but everything in the engine compartment is in great shape. It mostly sat in a garage, hense only 37k miles.

Did he ruin the engine driving 65 in 4th gear for 15 miles or maybe just fouled the plugs or something else?

No,that was the least of the problems,if it has a timing belt.I would look there and maybe check the fuel filter,the fuel system probaly has some gunk in it.This gasoline you buy now doesnt keep very long.

“Did he ruin the engine driving 65 in 4th gear for 15 miles or maybe just fouled the plugs or something else?”

No. I drove a 5 speed Jeep pickup from Indiana to Alaska in 4th gear while pulling a small travel trailer. 5th gear is just like overdrive so there is no “requirement” to use it.

This is a 22 year old vehicle. Despite the low mileage, lots of things degrade due to time alone. All the filters, anything made of rubber or plastic, the battery, etc. Do routine maintenance as though it had 220k miles on it. Replace the tires.

The gasoline, if it has been sitting for years, is probably turned to taffy.

Agreed; the driving in 4th gear has nothing to do with the running problem.

There were also various fuel supply options on these as near as I can remember. Some were TBI, some were “normal” fuel injection models, and some were carbureted.

That 10 year old battery needs to go as a first step.

It was driven once a week by a retired man. Dad had managed to also forget to refill tank on halfway point and so pulled into a fuel station 15 miles from me with it running on vapors.

So new battery, fuel filter, lines, and maybe check the plugs. The coolant hoses look good, but I will check them again, more thoroughly. The tires are old, but in decent shape and I know they wouldn’t cause the stalls.

Any other suggestions welcome; this can be my project car. Never owned a carborated engine before and under the hood is so roomy…

Unlikely timing belt…they either work perfectly or they don’t…nothing in between.

Driving in a lower gear won’t hurt anything except gas mileage…(as long as it was well below red-lining - which it probably was).

Start with the basics first…Battery and plugs…fuel filter is a good bet.

I’m assuming the engine is carbureted and there were several 4 cylinder options. These use timing belts and the truck needs a timing belt kit NOW if that job has never been done. The alternative is a potential snapped belt and engine damage.

The 6 cylinder option is TBI I think and uses a timing chain, not a belt.

If this engine is carbureted I would suspect that the running problem is with the carb. Offhand, it sounds like the idle circuit in the carb has a restriction. That could debris in an idle passage, aged gasoline turned to varnish, or the possibilty of a non-operative anti-diesel solenoid.

AD solenoids can be easily checked by leaving the key in the RUN position and repeatedly disconnecting and reconnecting the solenoid. If operative you should hear it click each time.

Nice try, but your dad did not hurt the engine one bit.
For the record, I’ve done that a few times myself. A few years back I drove 30 miles on the turnpike without realizing I was in 3rd. Didn’t hurt the car one bit. The amount of unnecessary wear I added means I’ll probably get 349,998 miles out of it instead of 350,000. Of course it’s already at 232,000 and no problems, so who knows?

I don’t know whytyou are ignoring the O2 code. A bad O2 sensor alone can make it undrinkable.

What do the O2 and fuel lights signify? I’m not familiar with those lights and would start with them.

Does the fuel light perhaps indicate the truck is low on fuel?

1993 should be OBD1 so any codes can be pulled with a paperclip.

I don’t really know much about this Isuzu truck . . .

But it does not have a carburetor. I believe the 1991 Jeep Grand Wagoneer was the last US-spec vehicle with a carburetor

In any case, no 1993 model year US-spec vehicle had a carburetor

That leaves TBI or some sort of EFI

check the manufacture date on the tires, there is a date code on them. If they are more than 10 years old, they are probably unsafe.

Tires Manufactured Since 2000: look for a 4 digit code, it is WWYY (W is week of the year), so a tire manufactured in the 12th week of 2005 would be 1205

Tires Manufactured Before 2000: look for a 3 digit code, it is WWY (W is week of the year), so a tire manufactured in the 12th week of 1998 would be 128 (or it could be 1988)

@db4690 - Rockauto lists carb parts for the '93 with the smaller 4. Surprised me…

AutoZone shows 3 engine options.
Two are four cylinders; one with a carb and one with fuel injectors.
The third option shown is a 3.1 V-6 with TBI.

O’Reillys shows a carb available for the L code engines.


NAPA and Advance Auto also show carbs and low pressure fuel pumps to go along with the carburetor.

Just a moment, I think there was a clue here that might have slipped by.

Dad had managed to also forget to refill tank on halfway point and so pulled into a fuel station 15 miles from me with it running on vapors.

This very first thing I would do is pour in a bottle of “Dry Gas” or a similar product. It’s very possible that he got a tank of gas that has water in it. If not, no harm done. But there may well be a connection between the tank of gas he bought and the sudden change in the way the car runs.

All of those parts sources mentioned have been known to show parts for non-US spec vehicles, in addition to the “correct” parts

I wouldn’t doubt it if there were non-US spec Isuzu trucks that still had a carb in 1993

I wonder if OP has popped the hood yet to determine just what fuel delivery system he has

A timing belt can certainly skip a tooth and make motor run bad. Buddy had civic with 100k miles and old belt. Drove fine every day to work. Drove 300 miles to friends house and belt broke during trip. Why does 10mile/day for yrs cause no strain but 100+ miles and belt breaks?

The OP said “the O2 light and the fuel light came on”.
There is no “O2 light”. There is only a Check Engine Light, and I suspect there’s a misunderstanding here by the OP. I suspect that Oldtimer perhaps “read into” the OP’s comment, an easy thing to do, but I think the OP needs first to have the failure codes read and post them.

NOTE: the “fuel light” is simply triggered by a float attached to the pump, however if there’s a blip in the car’s voltage from the engine sputtering or something similar some or all of your warning lights will blink. It could be that simple.

It almost sounds like it was running out of gasoline. Low fuel light, and O2 sensor light occurring suddenly? Yes, that’s the symptom you’d expect as it ran out of gas. It may be there’s gas in the tank, but it isn’t reaching the engine perhaps. Or the tank is actually nearly out but the gauge isn’t working so you didn’t realize it. Something like that is where I’d start.