Help

[SDWallhanger]

Okay guys my 2007 Yukon XL has been running great this last week and a half driving it back and forth to work no issues. No codes. No lights on the dash. So wife and I leave on a trip this morning to do some shopping. 45 minutes out of town we stop at a rest area to take a potty break and it stalls and will not restart. Which is the same thing it did the day we bought it used.
If you leave it sit for 20 or 30 minutes it will start right back up. I've changed the crankshaft positioning sensor the spark plugs the plug wires and the brake light switch. What is going on here should I replace the ECM?
TIA. Russell

 

[Foggy]

I would think fuel pump... after they sit and cool off, "sometimes" they
will fire right back up...
Kinda the same as a crank pos sensor - which you already have done.
The other thing is to really check your battery cables and connections and
related grounds.. If you have bad/weak wiring somewhere, the heat will
get to it

 

[wsteele]

You can buy a cheap little Bluetooth or WiFi dongle that plugs into your ODB port and with an app on your smart phone watch live data on what is happening in your engine, etc.

If you suspect a faulty fuel pump, you can watch the fuel pressure live, fuel trim, open loop versus closed loop, on and on.

Mine cost like $20 and the app was free, but I did do the lifetime pro upgrade on the app, which cost me an additional $6.

It will read codes and clear them, give you monitor status, live data, freeze frame, etc., etc., etc.

 

[ivin74]

I would think fuel pump... after they sit and cool off, "sometimes" they
will fire right back up...
get to it

I agree

Okay guys my 2007 Yukon XL has been running great this last week and a half driving it back and forth to work no issues. No codes. No lights on the dash. So wife and I leave on a trip this morning to do some shopping. 45 minutes out of town we stop at a rest area to take a potty break and it stalls and will not restart. Which is the same thing it did the day we bought it used.
If you leave it sit for 20 or 30 minutes it will start right back up. I've changed the crankshaft positioning sensor the spark plugs the plug wires and the brake light switch. What is going on here should I replace the ECM?
TIA. Russell

It would help to know more details of the vehicle. How many miles are on the suv? How long have you owned it? Do you keep up with the maintenance? What repairs have you done?

 

[donjetman]

Does the engine turn over? if not it could be the starter.

 

[SDWallhanger]

Has anyone ever figured this out? So frustrating!!

 

[Fless]

Has anyone ever figured this out? So frustrating!!

We could help if you can give us more info. I see that some questions were asked but not answered.

When it "doesn't start" could you be more specific? It doesn't turn over (crank)? Or it turns over (cranks) and doesn't fire up?