Hi guys..

Hope I got the topic right..

My 2005 GMC Savana 1500 with the 5.3 engine has suddenly been acting kinda strange. Not sure what it is but here goes.

Sometimes while driving the engine suddenly stops? You got to put it quickly in Neutral and turn the key to start and it starts right up.

Also while driving the engine stalls from time to time but it keeps going.
Don't know how to describe it but it's almost like it out of fuel or something like the ignition stops for 1 sec. But it keps on going.

This also happens when I start it up, and leave it at idle. Suddenly it stops?

All of the above does not happend every time.
An example start from home drive it like 10 miles no problems. Start it the next time, drive it like 1 mile and it stops and you start i right up.

Any had the similar problems? First I thought it had to be the fuel filter but on the second thought when you put the pedal to the floor it runs perfect from 0-100mph.

Recent things I've done, normal mantince sparkpluggs, sprak wires, oil+filter 2months ago.

Also it isn't any trouble codes....

Any suggestions??

Sorry if I misspelled anything but to many beers will do that to you

//Michael

 

Could be fuel pump.
The new systems are returnless and the filter is part of the pump. If you have never had the pump replaced then it could be on its way out, or getting starved from a bad filter.
Also i have read that these returnless sytems that don't allow fuel back to the tank get plugged up at the injectors. Any crud that gets by the filter ends up at the engine side of the fuel rails. Fixing this involves a full fuel injection service...(pulling the injectors and having the system full cleaned out)......

 

Thanks for your reply..

So what you're saying is that fuelfilter is a part of the pump?
Could someone guide me in the right direction.
Wheres the fuelpump located?
On top of the tank or is it in the little black box mounted on the front
of the tank?

//Michael

 

The fuel pump is inside the tank itself. You have to drop the tank to get to it.....not a small or ultra safe job.
The fuel filter, pump, pressure regulator and gauge sending unit are all one part on the newer returnless fuel systems......thanks gm.

 

Hi again..

So this is how the pump should look like?

Fuelpump
2005 GMC SAVANA 1500 5.3L V8 Fuel Pump | RockAuto

Where's this filter located?
Fuelfilter
2005 GMC SAVANA 1500 5.3L V8 Fuel Filter | RockAuto

A pic from the front of the fueltank.
With some question on it that I'm wondering about?




// Satyr

 

Sorry. I read that the returnless system is for the next generation of the 5.3 litre. Engine code LMF. Yours is a 1st gen, so you must have the older style.

Here is a link to a parts diagram.
VAPOR CANISTER & RELATED PARTS

 

Check the framerail between the tank and the engine for the fuel filter....

 

canucklehead thanks for all your answers and help..

As you said I belive that the engine I have is called LM7.

The pic i did earlier....


//Satyr

 

https://www.google.ca/imgres?imgurl=...vdyLM%3A&w=500

 

This time I barely made it home....

Kept starting and stopping all the time, but when I got home.
Thought I read the fault codes again, suddenly there where 2 pending codes.

P0335 Crankshaft position sensor a circuit
P0336 Crankshaft position sensor a circuit range/performance

If I got this right, the cpu doesn't know the position the crankshaft is in and therefore
turns the engine off?

//Satyr