Engine having trouble shutting down??

[JGheen]

So I did a search and couldn't find anything related but this has just started happening today... .

When I go to shut the engine off, it seems to keep running slightly and have trouble completely shutting down. Basically when I shut the key off, it pretty much "diesels" for a moment and has trouble shutting off... like the fuel shutoff is not working. Acts like a malfunctioning 12v fuel shutdown solenoid. . :-laf

Is this a problem with my CP3 or the FCA?? I have read stories in the past related to this but can't find them nor remember what it was..... please help.



Thanks guys,



Joe

 

[Prairie Dog]

Check your oil level and make sure you didn't lose a seal in the turbo ~ the engine can run on the oil. You can also take the air intake off the turbo and look for oil pooling.
Others know more about the CP3 ad FCA stuff than I do.

 

[JGheen]

Checked oil level, its fine and normal, smells fine... ... checked air inlet and its dry... .



Truck is bone stock, if turbo was loosing a seal, I would think it would runaway on me or have a high idle due to oil being burned..... I honestly have never read any threads about factory turbo failing seals on bone stock engines, thats not the case here but guess there may b some out there... ... its acting like it is just not shutting the fuel off when the key if turned off. It shuts off, but once key is turned off it still rumbles for a second or two.



Joe

 

[JMarketos]

key switch? take a close look at the radio or some other key-controlled accessory when you turn off the key. Is it just the engine that's appearing to lag on shutdown, or does the entire dash stay lit for an extra second or two ?

 

[JGheen]

Dash doesn't do anything funny when I shut it off just engine seems to just have trouble shutting completely down... . just like in a POS carburated gasser:-laf when it shuts off, bucks for a moment then finally shuts down, almost makes that same sound like a friggin carburated gasser:-laf.

It did it again this morning when I got to work, but seemed to buck n burp for a couple seconds longer. Almost didn't think it was gonna shut down.....



Another odd thing is the exhaust tone during acceleration thru say 1600-2400rpm is kinda "pulsey"... . if that is even a word. :-laf Normally its very smooth n steady but now it just sounds... . , well, like it pulses thru that rev range. Idle is very smooth, no popping or pulsing sounds or anything..... crusing down the freeway it sounds fine and smooth, just when I accelerate and put some pedal to it is when it sounds odd.



My 5yr/100K ran out on Sept 30th, engine just rolled over the 77K mark... . not planning on taking it to dealer unless I can't figure this out. Haven't had ANY engine problems with this thing until this, its like the whole truck knew the warranty has run out and now the problems start occuring cuz factory clutch is making funny noises too, so next weekend I will b putting in the new SBC street DD I ordered up.



Joe

 

[JMarketos]

Hmnnn. I really don't know what next to say. But then again, I'm not deeply experienced with these. Hopefully someone else will have something to offer. I'd recommend for the near future, check the engine oil level often. Do it with the truck parked in same spot, and let it sit for same amount of time after shutting off.

 

[drrhoades]

I have a 2006. I can pull the key out and hold it in my hand for probably 2 seconds before the engine finally quits. I always have the clutch pushed in instead of the transmission in neutral. Less banging around this way. Seems to me that it is the pressure in the line bleeding off allowing the engine to run slightly longer. Everything is very smooth and the engine runs great. My friends 2006 does the same thing.

 

[JGheen]

Guess I will continue to monitor the engine oil level for safe sakes...



Good to know someone else is having the same issue and your friend with an '06 as well.



So i am beginning to wonder if it could in fact be a faulty FCA, I mean, doesn't that accuator shut the fuel off when the engine shuts down as well as its other functions of fuel control? Guess I will use the search function and read up on FCA problems... .



Joe

 

[AH64ID]

I don't think a faulty FCA or CP3 could be the issue as the injectors are electronically fired, not via pop pressure.

 

[Wingate]

is the fuel mileage down?... do you have to twist the starter longer for the truck to start? any smoke while driving?

 

[JGheen]

Surprisingly there is less cranking and the engine fires up faster and my fuel mileage is still the same... ... no smoke while driving and just the normal small puff upon start up... ..... last 2 shutdowns this afternoon have been about the same..... turn key off and it just "diesels" for a good 2 seconds or so, tachometer does nothing once key is turned off... ...



drrhoades descibed it to the T... ... happens just like he mentioned

 

[AH64ID]

I wouldn't describe "dieseling" as smooth. When a gas motor "diesels" its very rough and rpms are not constant.

So does it "diesel" after shutdown, or stay running for a few seconds?

 

[JGheen]

I never said it "diesels smoothly"... ... it idles very smooth like normal after start up but when I turn the key off to shut it down it "diesels" for a couple seconds, has to be "dieseling" at say 100-300rpm if I had to guess before it stops rotating.



Joe

 

[Prairie Dog]

Anyone who owned an early 70's car sure knows what dieseling is LOL.
Here's a complete wild ars guess - any chance the air filter is completely clogged?

 

[cerberusiam]

Do you run any addtives?



Since the only way fuel is getting into the cylinder when the electronics shutdown is a sticking injector, I would dose it heavy with Power Service and 2 stroke oil to see if that makes a difference. Since startup and mpg hasn't suffered that doesn't really track either but the additives is a start.



The other way is shutting the key off is not shutting the injection system down for a couple seconds for some reason. How to test that is beyond what I can think of except replace the ignition switch.

 

[Prairie Dog]

What ever the cause this has got to go down as one of the strangest issues ever on here. Don't worry though Joe, we'll get this figured out no matter how much of your money we have to spend

 

[KLauber]

Clean it up!

Use Amsoil Diesel Concentrate Performance Fuel Additive. 1 ounce per 5 gallons of fuel.



That way Prairie Dog's post will ring true and we'll spend your money but at least your truck will run better!

 

[JGheen]

Your a funny guy P Dog... ... :-laf..... but this is why I have you guys, so I can spend thee least amount of money possible to fix the issue instead of throwing parts at it like I did ten years ago with my '98 12v. :-laf Learned a lot from that truck.



I run Power Service Diesel Kleen at every fill up using about 10oz or around 1/3 of that 32oz bottle u can buy @ Walmart.



Air filter is definately not clogged as I have been running a Stage 2 aFe filter system since about the 2K mile mark and I actually just installed a brand new filter less than 5000 miles ago as the old one was pretty tore up from numerous miles and half a dozen cleanings. The filter sock is still brand new looking and clean as a whistle.



I drive this truck about a total of 10-15 miles a day. 10 minutes and about 6 miles into work every morning then a short 1. 5 miles to the gym after work then another 10 min and 6 miles back home. 75% of that driving is freeway on Cali's famous I-5. Other driving is around the streets of the Valencia Industrial Center right by Mr. Guy Tripp's Duramax performance center of So Cal Diesel and the large city of Santa Clarita. Used to take long road trips in the past towing the '98 12v sled puller but that has long been sold and I can't afford that hobby anymore. :-laf Other than that, this truck has treated me VERY well since Oct of 2006 and has been trouble free until that damn warranty ran out on Sept 30th of this year!:-laf This has been the worst and most confusing diagnosis..... I really love the CR but I sure do miss the ease of diagnosing a 12v mechanically fueled truck. :-laf



Joe

 

[cerberusiam]

Used to take long road trips in the past towing the '98 12v sled puller but that has long been sold and I can't afford that hobby anymore

Well, there is your answer. You sold its buddy and now just use if for a grocery getter. Its MAD and LONELY. :-laf:-laf

 

[KLauber]

Brrrr!

The truck is constantly in a state of cold operational parameters... it wants to keep running so it can warm up!! Wait till HBarlow reads about your grocery getting!



While I've no idea on why or what is happening to your truck, I suggest you plug your truck in an hour before you leave every morning for the rest of its life. The tiny cost of the electricity may be offset by the lessened wear of running a cold truck and you may even get a tiny increase in fuel mileage by starting off warm. Win Win.



The Power Service is ok, but the Amsoil Concentrate does better, treats more fuel for about the same price and it will increase your fuel mileage by a few percentage points (although at 10-15 miles a day you won't retire on the savings ). More Winning!