Need help ASAP Please

[Habbibie]

2005 expy 5.4L 3v
This is a mechanical issue not a technical one.

Amigos the truck keeps stalling everytime I stop or slow down enough to a near stop, here's the symptoms in experiencing

1. It stutters when in low rpms. It drops to 400rpm when in idle while in drive, shakes then turns off if I don't drop it in neural and rev it

2. It stalled while I was in motion (foot off the throttle) at low rpms crawling in traffic on first gear

3. This just start happening an hour ago, never has it stalled on me before.

4. I noticed that when I'm accelerating while in 1st gear the engine bogs and feels like it isn't delivering power between 1000-3000rpms, it drives perfect in all other gears and pulls hard. (This has been happening for about a week now)

5. Took it for an alternator test @ autozone (just eliminating possible causes), battery failed (however while holding 12.4v & it's less than 4 months old 850cca/1050ca) but I understand a dead cell will cause it to fail... But a battery stalling the motor while it's running I don't think it's the actual cause here. alternator passed Pumping out a constant 14.36v

6. No clue if fuel pump is been replaced or still original (131,795 miles) but fuel filter is new & less than 1000 miles on it.

7. Spark plugs are new less than 500 mileson them, original coils and original fuel injectors, no CEL codes and none pending either

8. When it stalls, it restarts immediately, though twice when I restarted it.. it almost like skips a beat for a second before starting but still starts fine after.

9. It does have an exhaust leak (exhaust manifold) but been driving fine with it minus the hideous noise it makes.

10. I'm leaning heavily towards it being a fuel related problem (pump or sending unit)

Please any suggestions will help, cause when it's happening to you at the moment your mind doesn't think straight and I know I can figure this out if I was home but I'm 96 miles from home and the only thing in my mind is get this POS expedition home

 

[99WhiteC5Coupe]

Clean the inside of your throttle body with throttle body cleaner (not carburetor cleaner). The inside bore is probably very dirty and the edge of the butterfly valve probably has dirt deposits on it. When clean, the inside should look like shiny aluminum. If dirty, it will be very obvious.

When the valve closes (idle and at almost stop) there is not enough airflow around the blade to maintain a good idle.

You can remove the air intake hose to the throttle body and use a spray can to clean the inside (put plenty of old towels or paper towels under the throttle body to catch the runoff). It is easier to do this on a cool engine.

Once the inside looks clean, have a helper start the vehicle and you can spray more cleaner into the throttle body opening to clean it further while the helper maintains the idle (which will drop when you spray the cleaner inside the throttle body).

 

[Habbibie]

Clean the inside of your throttle body with throttle body cleaner (not carburetor cleaner). The inside bore is probably very dirty and the edge of the butterfly valve probably has dirt deposits on it. When clean, the inside should look like shiny aluminum. If dirty, it will be very obvious.

When the valve closes (idle and at almost stop) there is not enough airflow around the blade to maintain a good idle.

You can remove the air intake hose to the throttle body and use a spray can to clean the inside (put plenty of old towels or paper towels under the throttle body to catch the runoff). It is easier to do this on a cool engine.

Once the inside looks clean, have a helper start the vehicle and you can spray more cleaner into the throttle body opening to clean it further while the helper maintains the idle (which will drop when you spray the cleaner inside the throttle body).

Got it and just went ahead a did it, also I changed my VCT's while I'm at it (had new ones I intended on installing before but never did)

The throttle body was clean before I got to it, I cleaned it about 3 months ago but doesn't hurt to do it again.

This is what I used to clean it

 

[Habbibie]

Here's the two hoses I just cleaned...

 

[Habbibie]

Here's where I'm at now


Also I noticed that there's a puddle of transmission fluid under the radiator support, possibly coming from the pressure fittings on the transmission line? It pretty much looks like it sprayed all over with force cause oil is everywhere, there's no leaks at the transmission or near it itself just where I noticed it.

Edit: ok I just took it out for a test drive & it pulls hard on first gear without bogging out, actually for the first time since the motor swap it pulls that hard and holds the 1st gear all the way up to 3250rpm without a struggle.

I didn't faint, hesitate, stutter or shake indicating it wants to shut off while stopped or aproaching a stop while in gear....yet, tomorrow I'll get the real results to and back from work.

I did everything 99whiteC5coupe suggested plus I changed the VCT's and added a quart of oil (seemed low about 1 quart). I still have to track down the mysterious trans fluid sudden leak but hopefully the problem with stalling is corrected.

I'll keep on the look out for any other suggestions and advice, until then I'll keep you guys posted.

 

[stamp11127]

When the engine is up to temp and running the ecm enters closed loop operation. At this point it crunches the numbers based on input from all of the sensors. A sensor can be bad but still provide data that is within spec - it just isn't accurate.
I would verify fuel pressure is within spec then move on to the sensor data and finally check egr operation.
You should find and fix the trans fluid leak. If you don't it could get expensive quickly.

 

[Habbibie]

When the engine is up to temp and running the ecm enters closed loop operation. At this point it crunches the numbers based on input from all of the sensors. A sensor can be bad but still provide data that is within spec - it just isn't accurate.
I would verify fuel pressure is within spec then move on to the sensor data and finally check egr operation.
You should find and fix the trans fluid leak. If you don't it could get expensive quickly.

Ok thank you for the input stamp, i personally do not have the proper equipment to check fuel pressure or to read live data but you & me agree that the leak needs to be corrected as it could be the most expensive down the road. As far as what you implemented I will have to take it in to the dealer to get proper feed back and an accurate diagnostic on live data and if it's holding proper pressure

 

[stamp11127]

Dealers are evil (usually). Invest in a decent scanner instead of a code reader.
Start buying the needed tools and save yourself $ down the road. My obd2 scanner is pretty old but I looked this one over quickly:
https://www.amazon.com/Actron-CP9575-AutoScanner/product-reviews/B003IOKPLO

The price isn't bad compared to the USB cable & software I bought for my VW tdi's. That hit the wallet pretty good - $475. But, it is a needed tool.

 

[Habbibie]

I'll look into it but I am skeptical as I would be clueless trying to understand and read it properly, do you have any recommendations?

 

[stamp11127]

The more sensors it can monitor at once the better. Read the reviews on various models and compare features. Consider the ABS, SRS and TPMS features if the price is within reach. The big need is to monitor the live data from the sensors. Check tooltopia.com for the various scanners. Usually their descriptions are lacking but a Google search can get you the needed information. Before purchasing I usually try to download the user manual to get an idea of what the product can do.

Your exhaust leak is probably adding to the issues you are having since the data from that bank isn't accurate.

 

[Habbibie]

Dealers are evil (usually). Invest in a decent scanner instead of a code reader.
Start buying the needed tools and save yourself $ down the road. My obd2 scanner is pretty old but I looked this one over quickly:
https://www.amazon.com/Actron-CP9575-AutoScanner/product-reviews/B003IOKPLO

The price isn't bad compared to the USB cable & software I bought for my VW tdi's. That hit the wallet pretty good - $475. But, it is a needed tool.

Ok been comparing for a couple hours now, I got my heart set on this on

https://www.amazon.com/gp/aw/d/B011...rds=cp9680&dpPl=1&dpID=41amrvQ+6dL&ref=plSrch

I can get it for $150-180 local compare to $200+ online

 

[docraymund]

If you can take it to a transmission shop near where you are, much better. I think you have a trans problem causing your engine to stall while in drive (excessive resistance perhaps?). May be the torque converter.

 

[Habbibie]

If you can take it to a transmission shop near where you are, much better. I think you have a trans problem causing your engine to stall while in drive (excessive resistance perhaps?). May be the torque converter.

I'll have to swing by the shop that rebuilt it & have them scope it out since it's still under warranty, but I don't think the transmission is suspect #1 here

Transmission was rebuilt 15,000 miles ago, fluid is still at proper level & very pink, shifts like butter

 

[stamp11127]

Don't pull the trigger on it just yet as these are just fancy code readers with a little screen.

This is more than your budget but take a look on ebay at the used Snap-on Solus. The wider screen spoils you since it displays data over longer time periods plus depending on which model most will allow you to command outputs to various actuators. These are what is needed to really diagnose & avoid tossing parts at a problem.

Check the vehicle operation like you said earlier then check the egr valve operation if the problem still exists.

 

[JoeD]

Habbibie - check the lower trans line fitting on the rad, our 04 just had this fitting fail just a few weeks after a brake line went under the rad.
I saw the residual staining and wetness and thought it was from brake fluid and didnt think anything of it until the wife said it wouldn't move.

~$200 for new fittings and lines from fmco + fluid and I hope its not toasted.

BTW - the fitting and lines are rust rotted

 

[Habbibie]

Habbibie - check the lower trans line fitting on the rad, our 04 just had this fitting fail just a few weeks after a brake line went under the rad.
I saw the residual staining and wetness and thought it was from brake fluid and didnt think anything of it until the wife said it wouldn't move.

~$200 for new fittings and lines from fmco + fluid and I hope its not toasted.

BTW - the fitting and lines are rust rotted

I'll look into it soon, I'll wait till it's a dry day outside. Right now it's wet and hard to distinguish between water and oil

 

[Boose]

Regarding your stalling issue, I experienced the exact same thing with my 05 EB. As the 05 was the first year of the 3V & throttle by wire, there were issues. The throttle position sensor & throttle actuator were suspect. I changed out the entire throttle body in 2009 with a new Factory unit. It's never stumbled since. the entire throttle body was cheaper than buying the sensors individually. I want to say there was a TSB in 2007/2008 that spoke to this. If you replace the TB, go with a unit from 2009 or later. the whole unit was under $300...
Regarding the trans lines, both of my cooler lines have been replaced. The steel rotted through a few years ago.

 

[Habbibie]

Regarding your stalling issue, I experienced the exact same thing with my 05 EB. As the 05 was the first year of the 3V & throttle by wire, there were issues. The throttle position sensor & throttle actuator were suspect. I changed out the entire throttle body in 2009 with a new Factory unit. It's never stumbled since. the entire throttle body was cheaper than buying the sensors individually. I want to say there was a TSB in 2007/2008 that spoke to this. If you replace the TB, go with a unit from 2009 or later. the whole unit was under $300...
Regarding the trans lines, both of my cooler lines have been replaced. The steel rotted through a few years ago.

Great info. Thank you Boose, It hasn't stalled since yesterday but I didn't really hit any traffic jams, the trans lines surprisingly aren't rotted or rusted, the fittings are tighter than all hell too.
I still haven't discovered where the leak came from but it hasn't leaked since while parked??? I'm gonna check the fluid level tomorrow during the day and the results will determine my next move of action is.

Here's how the trans line looked when I found the leak yesterday.... Like I said kinda mysterious where it came from but the lines themselves are dry

 

[Habbibie]

Well I checked the transmission fluid, seems fine, maybe half a quart low but nothing that would indicate a constant leak...

 

[Boose]

In order to confirm my lines that were leaking, I sprayed liberally with brake cleaner. This removed all oil. Then blew dry with compressed air. they soon became "wet" again with fluid. I would spray all of the undercarriage from the front axle to the fan shroud to dry everything of oil. It'll be easier to spot with a "clean slate".