Engine stalled, help!

[yukonese]

This is the first time my lovely 01 Yukon didn't make it home, in 11 years.

This morning, it ran smoothly as normal. When it's time to pick kids up from the Sunday class, the engine started OK but dropped to 1 or 2 hundreds RPM in 2~5 seconds, and struggled to rev up for a couple times, then stopped. Tried to push the gas paddle, no help. Repeated a couple times, same symptom. There seemed some smoke out from the pipe.

The Service Engine Light did come on once, OBD code said P0420-1. Does that mean O2 sensor bad? Upstream or downstream? All 4 need to be replaced? A bad catalytic converter can make the engine stall? A catalytic converter goes bad all a sudden? Any other possibility?

I have 69K miles on this 5.3L V8. I need some opinions before I call the tow truck. Thanks for your advices in advance.

 

[chauncey0337]

Getting fuel pressure? Can you hear the sound of the fuel pump when you turn the key on?

 

[M3PO]

Getting fuel pressure? Can you hear the sound of the fuel pump when you turn the key on?

Yep, best place to start with these trucks, the fuel pumps are always suspect.


Try beating on the tank with a rubber mallet, and then try to start. I thought this method was BS, until I saw my buddy do it, and he was able to save a tow and drive his truck to the dealer for a pump.

 

[Sprayed99]

I have also done the fuel tank bang to get me home. I had to do it on the highway with my shoe LOL.

 

[yukonese]

If it is the pump, how to explain the engine can start successfully every time? Because the gas pressure can't keep up? The parking place is not so quiet, I will need to pay extra attention to the pump whining. Thanks.

 

[bankswood]

I have an 01 Yukon and when my fuel pump failed I coruld start it but it would quit. I am guessing that the pump would "whirl" suring start up just enough to create some pressure.

 

[DenaliAK]

Just one more for fuel pump. Same symptoms my truck had. It would start fine. Put it into gear and it would immediately drop RPM's and stall.

 

[bkboatnsleds]

or check fuel gauge too,, Mine would ready 1/2 and be empty, but all part of the pump too.

 

[yukonese]

It's the pump!

I did some tank bangs, but unhelpful. Since my insurance covers towing, I had my Yukon shipped to a reputable shop by a flat bed. The shop owner told me there was a Tahoe who had a dead fuel pump today, too. What kind of ACDelco quality!

Why GM wanted to put the pump inside of the tank? Is it fun to drop the whole tank? Hope this new pump will last another 11 years!

 

[hoe]

yea, had to sucker punch the tank 3-4 times with a half tank of gas before. My pump was failing when I bought my truck, and fuel gauge could needle dive at anytime. But she ran great, until the pump actually failed/weakened. But the new pump has solved all problems.

You can drop the tank down half way. I have done this with just 2 jack stands on the side of the truck, no shop lift. Once you have enuff clearance to get the pump unit out your golden. Its actually a easy job. 2 straps and the tanks coming down. You may have to rewire for the new style plug to stock harness as well. They pack it as a kit comes with your new pump.

 

[Gzes]

When my pump was going out it would start stall then die then I had to restart it and I could drive then.. Also the needle would go nuts then new pump and problem solved

 

[yukonese]

Thanks for the experience sharing, I'll try it next time (hope it is not happening too soon), save me $300.
I just refueled the tank 1 mile before the pump went bad. I guess it would be very heavy with 26 gallon gas in there. At least the shop I went put every drop back. The dealer who replaced my leaky tank when it's new vaporized 1/3 of the tank.

 

[PwtrSS_OakCliff]

Mine marked 1/4 and it was empty.. It took almost 8 gallons to get it started once it died..

 

[AppleJuz]

It might be a bad fuel pump. I also suggest changing to a Magnaflow Car Catalytic Converter Accessories just to be on the safe side as it could've gotten some damage when the fuel pump went bad/dead. I'm an old guy and my methods may be a little high on the cost, but I dislike having anymore difficulties in the near future.

 

[SunlitComet]

For now ignore the 0420 code unless it comes back after erasing it. It is likely a reactionary response to the sudden leaned out condition of low fuel pressure. It created a gaseous anomaly in the exhaust system.