01 crew cab dies randomly

[crews10]

I'll start off by saying I recently picked up a 01 crew cab s10. All stock except I turned my torsions about an inch. I am from Tucson az so it's been hot lately and my s10 started shutting off. No cel, and I can put it in neutral and start it back up usually. Except today I had to pull over cuz it just backfired and didn't want to start. I recently replaced my fuel lines and filter. Any ideas?

[HenryJ]

You say it has been hot. Has the engine been heating up too?
Has the gas mileage been worse than usual?
Ever smell rotten eggs?
Does it run very quiet?

The backfire and fact that it usually starts after stopping , add the heat and I am thinking a plugged cat. Symptoms you listed add up.

[crews10]

Well today I was driving, it was 107 outside and my truck shut off every mile or so. This time it bogged down then shut off. Seems like it's running outta gas but I just put $25 in my tank and I can hear my fuel pump running. No rotten egg smell, it is very quiet, I run full synthetic oils so it runs smooth. I get 17mpg average the way I drive and haven't noticed any difference. I'm thinking a bad fuel pump or the ground in the back or maybe charcoal canister. I can smell fuel when it dies but it's not dripping and my fuel lines are dry.

[Blacknoma]

These engines only like the regular fuel pressure and they constantly run like they are bogging down and are powerless if the fuel pressure is off.
To me it sounds like a bad cat. If its not that, I would recommend a basic tune up with high quality plugs, wires, cap, and rotor then go from there.
What temp is your engine running at?

[HenryJ]

Gas smell might indicate injector line or fuel line leaks. Again gas mileage is usually in the dumper.

I am going with a wild card here and having you check the battery cable connections. Make sure they are tight. Not just the bolts, the cables. Clean and tight. The bolts can bottom in the holes and the cable still not tight. Easy to check.

Next get a fuel pressure gauge and do the fuel system checks. There is a very good thread around here about that. It will check fuel pump condition, regulator, injectors, etc.

While you are under the hood, check the distributor and cap. Cracks in the housing are notorious. This leaves the cap loose. Heed the plastic distributor warnings. Corroded contacts are another problem. Make sure the vents are clean. Blow them out with compressed air. All the time looking, seek the gas smell.

[crews10]

Thanks guys. This is my 4th s10, had an 02 ex cab with a 2.2, had a 98 regular cab with a 4.3, a bagged 94 with a 2.2 and now this one. This isn't my 1st rodeo with an s10 but I am stumped. It just shuts off. Radio stays on and my ad stays on but I will check things tomorrow. My dad has an 04 gmc sierra with a 4.8 and his does the exact same thing. Only when it's above 100 degrees my truck shuts off. Below 100 then it runs perfect. My temp never runs above 200* but wouldn't a bad cat throw a cel?

[HenryJ]

Bad cat will not set the CEL / MIL. A temp gun would be helpful to diagnose that. You should see about 100+ after the cat.

[crews10]

Ok thanks for the replys. If the cat is bad, how hot will it read? Under 100?

[HenryJ]

Hotter after, not the same or hotter before.

[Blacknoma]

I saw a bad cat once that would glow red-hot where you could see the glow at night after driving for a while... The operator put the truck through hell daily, so I wouldn't think yours would be that bad... I am still amazed his was that bad.
Hope you have this figured out soon. let us know!

[crews10]

Well the truck has 160k on it and came from kentucky. I drive all my vehicles very carefully, most of the time, but I can't afford a temperature gun right now so the truck sits. Haven't started it in almost a week. I got a child and a baby so I dont want to risk being stranded somewhere. How about hollowing out my cat? Would that help my bad cat problem?

[HenryJ]

You can try removing both up stream O2 sensors and see if the relief in back pressure helps it run better. If it does then the cat needs repair. I broomsticked / gutted mine. A band clamp and cut it off right in front. On my older S-10 I rewelded mine with a flange so that it could be unbolted in the future. The precat I removed completely and replaced with a piece of pipe on the crew cab. The main cat was just fine and did not need modification or replacement.
If you have a good muffler shop, they might test it for you. Some drill a small hole and check using a pressure gauge. Others use the IR temp guns.

[crews10]

Maybe a dumb question but what's the precat?

[HenryJ]

It is the little cat before the main cat. They are notorious for plugging. It was suppose to be a small cat that heated up quicker and help to control emissions. Nice idea. Just didn't work out as well. Mine and several others have plugged. I replaced mine with a straight through pipe and let the main cat do the job. That worked for me.

[crews10]

Ok thanks. Yesterday I filled up my tank completely. $51.00 worth. Drove all over and it was 104 outside. Didn't sputter a bit. Someone else suggested fuel pump relay. Could it be that? I couldn't take my cat off today cuz I don't have a welder to put it back on

[HenryJ]

No need to remove the cat if it is not bad. A band clamp can put it back together until you can weld it.
By all means do the simple stuff first. Fuel system checks. The relay either works or it doesn't. They are not a common failure point. If you regularly run on the bottom half of the tank a pump failure is very possible. Fuel is the cooling media for the pump. Check the ignition components too.

The backfire and heat led me down the road to the cat. Backfires are also possible with a bad cap and rotor. Less likely with the fuel issues.

[crews10]

Well I guess I start somewhere until I find my problem. Thanks for the suggestions. I'll start by replacing my cat and work from there to my fuel pump and on. Going to take my boat to the lake so hope it makes it. I'll let you know what I figure out on parts. My fuel gauge reads wrong and AutoZone plugged in my obd2 and It said I need a sending unit so maybe I'll replace my fuel pump first. What's the easier way to change my pump? Pull the bed or drop the tank?

[Horsehammerr]

Drop the tank ! Removal of bed is 100% waste of time, you CAN NOT access the pump unit from the top, NO WAY. It sets under the cab and can not be taken out that way.

[HenryJ]

Well I guess I start somewhere until I find my problem. Thanks for the suggestions. I'll start by replacing my cat and work from there to my fuel pump and on. Going to take my boat to the lake so hope it makes it. I'll let you know what I figure out on parts. My fuel gauge reads wrong and AutoZone plugged in my obd2 and It said I need a sending unit so maybe I'll replace my fuel pump first. What's the easier way to change my pump? Pull the bed or drop the tank?

A few things here.
Don't just gut and replace parts before you do your detective work and isolate the culprit. The cat is expensive. Beg or borrow a temp gun and check it. It should be 100F hotter after, not the same or hotter before. Your trip pulling the boat will also tell the tale. That trip should over heat it and suck all the power away to the point of crippling the truck if it is a bad cat. They don't get better, only much worse if they are failing.

New clue: " My fuel gauge reads wrong "

Replace the fuel pump. Don't go cheap. Get the Delphi original replacement pump. Cut the wiring and install the new pigtail with the new connector. There is no other option. The stock connector is being blamed as part of the problem with the pump failures. They say it delivers in adequate amperage and contributes to early pump failures.

Drop the tank. Easily done. Way easier than pulling the bed on these trucks. Once you have done one it only takes a couple hours to replace one.

[crews10]

Ok thanks. The reason I asked about pulling the bed is my dads sierra ex cab we pulled the bed but my truck came from Kentucky so the bolts for the gas tank straps are rusted shut. Just thought to ask questions here before I started throwing money at it. Trying to sell it but nobody wants it yet.

[crews10]

Well I'm pretty sure I have a bad cat. Last few days I've been getting horrible gas mileage and today I ran wot till I hit 60mph. Smelled bad and didn't have the power it should. Also, when I came to a stop, my truck wanted to die. Rpms came down to under 1k and it sputtered but stayed running. As soon as I sell my cb and antenna then I'm gonna buy a cat.

[HenryJ]

Gotta sawzall? Gut it. A band clamp will put it back together until it can be replaced and welded.

[roadrunner]

My 01 runs happy with the pipe I used to replace the pre-cat. Your problems sound identical to what I experienced prior to the cat-ectomy.

[crews10]

I want to replace my pre cat with a straight pipe and hollow my cat but short on cash.

[roadrunner]

I want to replace my pre cat with a straight pipe and hollow my cat but short on cash.

IIRC my "replacement" pipe cost me six bucks. I bought a piece at a local shop had them expand the ends to fit my pipes and welded it in myself.

[Blacknoma]

i agree with HenryJ. Exhaust clamps work well for temp stuff... put in a replacement pipe and clamp it in and get a shop to weld it in later when you have cash. Better to have a running and reliable truck I think.

[crews10]

How long of a piece of pipe do I need?

[Blacknoma]

If I were in the states with my truck, i would measure for you... but I'm not. Just get a section as long as the one you cut out. Auto-zone will have pipe sections and clamps if you want a 1-stop shop. Or you could get a piece from an exhaust place much cheaper I believe. If you have a sawzall or a hacksaw and a basic ratchet set for the clams, your good to go!

Measure it out, cut out your section (pre-cat), "broom stick" your cat, clamp in your new section, and see how it goes.

[Lil-j]

Older thread I know but I'd like to add that a bad ignition coil can give all those symptoms from crews10's post from 25 June fit what happened to my truck last year. I found the coil was bad by accident, went to throttle the engine up by hand and got zapped by the spark jumping the coil wire to the bracket.

[Lil-j]

Also, the first post mentions that the OP replaced the fuel lines. I'm in the same boat, I need new metal lines and can't find them. The ones that run on the left frame rail.