Sputtering and coughing

[Randy Whistler]

Once again, I must beseech the fountain of knowledge for assistance.

On Tues. this week, I drove the Tahoe from the east side to the west side with no trouble at all. Drove a bit on the west side, made one stop, and then it happened. When I left the last stop, all of a sudden the 'hoe started to sputter and cough, like it was out of gas.(according to the gauge, which has worked prior, I had about 1/4 tank). I don't know how else to describe it. It would not accelerate, idled roughly, and died once or twice, the 2nd time forcing me to pull off to a side street. Once we came to a stop, I tried a few times to start it, resulting in a start but no power, cough/sputter, etc. After about 2 or 3 minutes, it started up. I drove a few blocks around, and was able to get it back across town, seemingly normal.

A trip to the local Wally World the next day was uneventful.

An attempted trip today to the same Wally World did not go so well. Same thing, cough/sputter, stuck in the middle of the road. Finally got it started after about 2 or 3 minutes, and quickly drove back home to get the other car.

A couple of weeks back, I took a 5 gal gas can I had from last fall, and poured it into the Tahoe. Just mentioning as background, but it was fine until I did this. The can did not have a cover for the spout, and was outside for a time and may have gotten rain down the spout. Yes, I know, but lets not talk about that right now. . .

It is not throwing any codes that I can find. When it runs, it seems to run fine. We went to a local taco place on Thurs., across town, idled in the parking lot while eating, and back across town but didn't notice any major issues.

I have dumped 2 bottles of HEET into it today, with some good gasoline from a clean gas can, and am letting it stew for a little while - I suspect the gas in the previous can might have been water-contaminated maybe, but don't have any proof.

So here's my thoughts:

1. Bad gas
2. Fuel supply line issue -filter perhaps?
3. Gremlins

With it not showing any codes, and it acting exactly like it just ran out of gas, I suspect it a fuel issue rather than mechanical. I'm going to check later today or tomorrow to see if the HEET did anything.

As always, any thoughts and advice greatly appreciated!!

 

[OR VietVet]

I would get a fuel pressure gauge on it and have a long enough hose to snake out the back of the hood and tape gauge to w/s to see while you are driving. How old is the pump? The fuel filter? How did you check for codes? How old are the plugs and wires?

 

[Randy Whistler]

I would get a fuel pressure gauge on it and have a long enough hose to snake out the back of the hood and tape gauge to w/s to see while you are driving. How old is the pump? The fuel filter? How did you check for codes? How old are the plugs and wires?

Good questions. I have no info on the pump or filter, have not been dealt with since I've owned it. I have a code reader to plug in, but it showed no codes, either stored or pending. Plugs/wires are the same as the fuel pump and filter. I had wondered about the plugs/wires, actually, but had placed it on the back burner.

 

[OR VietVet]

Then, at this point, you need to rent or buy an inexpensive fuel pressure gauge and hook it up like I said and drive the rig and hope it messes up while you are driving and can see the fuel pressure.

Plus, check this out: https://www.fixmyoldride.com/Chevro...e7e5cd24ed24635&at_ab=per-2&at_pos=3&at_tot=4

 

[Randy Whistler]

Plus, check this out: https://www.fixmyoldride.com/Chevro...e7e5cd24ed24635&at_ab=per-2&at_pos=3&at_tot=4

Ooh! Ooh! Ooh! (waves excitedly) We may have a winner here!

I'm a retired IT manager - started as a copper guy(phone co., for those who don't know) back in the dark ages when everyone had land lines. If you didn't understand grounding, you had no future whatsoever with the Bell Company!!

That being said, for some time lately, the Security light would flash on, my airbag lite would go on/off(airbag relay Not installed so on is normal), and my PRNDL indicator would go on/off sometimes when operating a window or other power accessory(already fixed the cold solder on the instrument cluster), at least as I recall. I was suspicious of a power issue, but thought battery or battery cables, hadn't thought of grounding. I have a PT Cruiser that had a similar issue a few years back. Would crank great, but wouldn't run cause the ground bus for the fuel pump had crapped!

The fuel thing will be looked into as well - have the fuel tank/pump on the project board, but just hasn't been messed with yet. Thanks so much for this suggestion, with the other oddities that have been happening, this certainly seems in the realm of possibilities!!

 

[OR VietVet]

That is why so many times a member is asking about one problem but if they can they need to share all the recent problems as well because so much can be tied together. If you live in a salt on the roads state, there is a good chance you will have grounding problems eventually.

 

[Randy Whistler]

OK, continuing on this path of a grounding issue - I have not yet had a chance to check out the wiring issues, but that will be tomorrow hopefully. I wanted to outline my thoughts and make sure i'm on the right path. As a refresher, this truck has run fine for 2 years or so, and just recently started sputtering like it was out of gas. Before I tackle the fuel side, I'm going to check the grounding side. Here is a list of the symptoms to date:

security lite comes on when a power load exists. Example: headlights on, front/rear blowers on, A/C on, light might come on and would go out when load was reduced by turning off lights, lowering fan speed, etc.

PRNDL indicator would sometimes not "highlight" the selection when power load, like operating windows, door locks, etc. Not consistent.

Recent problems; acting like out of gas, sputtering, dies, so far has eventually restarted. I should also note that, when it would restart and run, the security light would go on/off, on/off, at intervals when I got it restarted. All other gauges and functions seemed normal, as well as driving home without sputtering. Could be fuel related, quite true, but could be power, too.

As noted previously, I've had another vehicle that had a similar issue. Also, my background is telecommunications/electronics, so I'm relatively familiar with grounding - the Bell Companies make sure you learn that first! Because of my background, having another vehicle do a similar thing, the listed evidence above, and the seemingly intermittent issue with the sputtering, I'm leaning toward a power/grounding issue. I intend to follow/clean/repair all the ground sides I can find on Monday. is there anything else to consider? Is there a battery control module, power controller or some other magic device I should look into as well?

As said above, have not ruled out the fuel side by any means. The power side is just the first step.

And finally, thank you all for every bit of help and advice I've received! It is truly appreciated!

 

[5strmtrp]

Once again, I must beseech the fountain of knowledge for assistance.

On Tues. this week, I drove the Tahoe from the east side to the west side with no trouble at all. Drove a bit on the west side, made one stop, and then it happened. When I left the last stop, all of a sudden the 'hoe started to sputter and cough, like it was out of gas.(according to the gauge, which has worked prior, I had about 1/4 tank). I don't know how else to describe it. It would not accelerate, idled roughly, and died once or twice, the 2nd time forcing me to pull off to a side street. Once we came to a stop, I tried a few times to start it, resulting in a start but no power, cough/sputter, etc. After about 2 or 3 minutes, it started up. I drove a few blocks around, and was able to get it back across town, seemingly normal.

A trip to the local Wally World the next day was uneventful.

An attempted trip today to the same Wally World did not go so well. Same thing, cough/sputter, stuck in the middle of the road. Finally got it started after about 2 or 3 minutes, and quickly drove back home to get the other car.

A couple of weeks back, I took a 5 gal gas can I had from last fall, and poured it into the Tahoe. Just mentioning as background, but it was fine until I did this. The can did not have a cover for the spout, and was outside for a time and may have gotten rain down the spout. Yes, I know, but lets not talk about that right now. . .

It is not throwing any codes that I can find. When it runs, it seems to run fine. We went to a local taco place on Thurs., across town, idled in the parking lot while eating, and back across town but didn't notice any major issues.

I have dumped 2 bottles of HEET into it today, with some good gasoline from a clean gas can, and am letting it stew for a little while - I suspect the gas in the previous can might have been water-contaminated maybe, but don't have any proof.

So here's my thoughts:

1. Bad gas
2. Fuel supply line issue -filter perhaps?
3. Gremlins

With it not showing any codes, and it acting exactly like it just ran out of gas, I suspect it a fuel issue rather than mechanical. I'm going to check later today or tomorrow to see if the HEET did anything.

As always, any thoughts and advice greatly appreciated!!

Saw this come up at the bottom of a post.

By the look of you post your talking about an 01-07 truck.

Your symptoms are EXACTLY what I put up with for a few weeks. All good then bammo limp mode! I sincerely hope the info below helps out.

My 03 Silverado did the same crap turned out to be a Ground wire.

The ground wire that has been causing this issue on a lot of these trucks is located behind the intake closest to the
firewall. Dead center of the motor, feel around there following the harness.

If it’s the ground wire I’m referring to, splice in a section of wire loosen the ground strap against the firewall closest to your brake booster retighten the strap with your splice added in.

Thai should take care of what’s been going on. Easy cheesy fix, but a frigging PITA. to get your ride acting like it’s supposed to.

 

[Randy Whistler]

Thanks, I appreciate the info! It's a 2000, but IiRC, the 2000's are in that group. In any event that's another place to look, and that's what i was wondering about! I'm not greatly familiar with GM products(though getting much, much better lately! ) so having hearing where to look can be a timesaver(not to mention life saver!)!

 

[5strmtrp]

Thanks, I appreciate the info! It's a 2000, but IiRC, the 2000's are in that group. In any event that's another place to look, and that's what i was wondering about! I'm not greatly familiar with GM products(though getting much, much better lately! ) so having hearing where to look can be a timesaver(not to mention life saver!)!

Randy,

I hope it’s just this ground wire for you. Like I mentioned your symptoms are a flashback to what was happening to me.