2003 Escalade Stumbles / Stalls

[stealth09]

So I have a 2003 Cadillac Escalade that stumbles and stalls if throttle is applied to it.

Background info:

A few weeks ago I replaced my fuel pump as the original one fried. I drove the car for 1 day after I replaced it with an OEM AC Delco. Everything was fine.

I take off on vacation and come back 2.5 weeks later. My battery is dead. My brother boosts the Escalade by connecting the positive terminals together then the negative on the battery of the car that is doing boosting. He accidentally touches the negative booster cable on my Escalade with the positive one that is on the battery. He noticed that the booster cable gets red hot. He says it touched for only a second...

He drove it for a couple hours with no issues according to him.

I drive it the next day and notice that it stumbles when I floor the vehicle. I drive it some more and noticed that it starts to stall out when it stumbles.

The next day I start it up and it drives fine for the first minute. After a minute any minor increase in throttle causes it to stumble and die... It keeps doing this. After every restart it drives fine for the first 30 seconds unless you floor it, then after the 30 seconds any throttle stalls it out. If I apply a very minute amount of throttle it will drive, or if I get to speed it will maintain speed with minimal throttle.

I replace the fuel filter thinking it is clogged. That doesn't do the trick. I also clean the throttle body and that does nothing.

I took out the two upstream O2 sensors to bleed of pressure if I had clogged cats and that did nothing.

I checked the grounds on the drivers side frame rail, they look good.

I replaced the crankshaft position sensor, that did nothing.

I unplugged the MAF, no difference.

Unplugged the MAP, no difference.

I pulled the vacuum line off of the fuel pressure regulator and it is dry.

I checked the fuel pressure and it is at 49-50 PSI with the key on and engine off. It is at 47 PSI when idling.

When I give it gas in park, it will cause the fuel pressure to drop to 25 PSI until it dies out...

So I ran a code reader and there were two codes, one for system to lean bank 1 and one for Crank/Cam sensor, but that could of been due to me messing with those.

I cleared the codes and they never returned.

I am thinking that my brother could have fried something on my ECU perhaps?

Any insight?

 

[Rivieraracing]

Wow man, you've done all the crap I would have done and suggested, almost wondering that through all the dead battery/jump starting that you had to do before the problems came up, I'm wondering if you truck will have to go through the relearn/throttle procedure (can't remember exactly what that is called offhand).
I had to do that once when I unhooked my battery for a bit of time, made the truck idle like crap. If I remember right, there was a process you could go through to make it relearn it faster than driving it around like that!! Give me a bit today, I'll go through my book later today and see if I can find the procedure for you!

 

[stealth09]

That would be greatly appreciated. I have fiddled with it for 6 days now, and will take it into the dealer on Monday or Tuesday if I can't fix it.

 

[stealth09]

So I did some more troubleshooting and I think my fuel pump fuse or relay? The one that is grey with 4 prongs, is overheating.

I swapped it with the one for the HI BEAMS and it ran good for 30 minutes, but then the problem came up again...

 

[Rivieraracing]

So I did some more troubleshooting and I think my fuel pump fuse or relay? The one that is grey with 4 prongs, is overheating.

I swapped it with the one for the HI BEAMS and it ran good for 30 minutes, but then the problem came up again...

So, when you swapped it out for your high beams relay, did you try to use high beams with the thought to be bad relay and if so did it work?

---------- Post added at 07:03 PM ---------- Previous post was at 06:50 PM ----------

Also, finally found the section in my Haynes manual that I was talking about for the relearn, took me over an hour to find because it's so easy to read over and I always forget where I have found it in the past!! Never again though, highlighted and marked the page for fast future reference!! lol

This is what it says about disconnecting the battery and what can happen:

b) The engine management system's PCM will lose the information stored in its memory when the battery is disconnected. This included idling and operating values, and any fault codes detected. Whenever the battery is disconnected, the information relating to idle speed control and other operating values will have to be re-programmed into the unit's memory. Then PCM does this by itself, but until then, there may be surging, hesitation, erratic idle and a generally inferior level of performance.

It says this to fix the problem:
"To allow the PCM to relearn these values, start the engine and run it as close to idle speed as possible until it reaches its normal operating temperature, then run it for approximately two minutes at 1200 rpm. Next, drive the vehicle as far as necessary - approximately 5 miles of varied driving condition is usually sufficient - to complete the relearning process."

Hope this helps your problem out, I've had to do this process 2 times in the time I've owned my truck, both times due to disconnecting the battery. Every other time the truck has been fine and re calibrated itself without having to go through this, even this last time I changed out my battery the other day!

 

[Volant1]

Its the fuel pump, I ran through the same problem 4 times

 

[Rivieraracing]

Did you come up with anything Stealth09?