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Slow on fire up

K

knkreb

The Bus Driver is here!
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Location
Delaware
Ok, I know it's been a while and my skills are a little rusty, but I can't seem to come up with any ideas....

Here's the deal: All my 6.5's have always started very quickly... as in 1 second or less. With bus 1, even at 20 degrees outside, it would light up in about a half a crank. This new to me van, seems to be less than ideal on starting. Cold, warm or hot it takes about 2 to 3+ seconds on the starter to get it to fire. 134,000 miles.

Appears to have new glow plugs and injectors. PMD remote mounted already. Crank speed seems comparable to all the others. Fixed a fuel leak on the filter. Lift pump works. No codes or problems. New fuel cap. MPG's appear okay.

Perplexed I am. Anything I forgot?
 
When I got it, it was just peeing fuel out of the filter. It was double gasket on the water in fuel sensor. No other leaks found. No fish-bite, misfire, etc, or optical sensor codes that would be associated with air in the fuel system. No smell of fuel either.
 
Just because it has newer injectors, it does not mean they are good injectors. So many people out there are buying the cut rate injectors off of Ebay anymore it is tough to know if they are good or not. Many of these bargain parts are worse than the high milage parts they are replacing to. I would have the injectors pop tested if it was mine.
 
I was going to say fuel filter condition, and to check the injectors as well. :) All good info given!

Maybe a check of the oil to see if your getting any fuel contamination. Also, check the primer on top of the fuel filter. I won't say what it should be like. :rof: I would be leaning toward a fuel prime issue.

I would go ahead and check to see if there are any "hidden" codes that are stored and just not showing, if you can.
 
I am gonna get the filter changed. (on the to-do list) but I'm doubtful it's the filter at the moment. She will set you back in the seat with you want her to go. I've had dirty filters before on bus 1, and you can just feel the power leave ya when they plug up. As a precautionary item, I'm still doing the filter due to unsure of when last it was done.

No pending codes either. I got one of the ScanGauges II so I can see real time OBD-II data. No codes pending or other issues to report.

I was also wondering if maybe a hot start issue like the old DB2 pumps might be a problem, but she starts.
 
As always, you're right on top of it Kevin! :thumbsup: Maybe bad fuel? Just thinking outloud here. And, just double check on the fuel prime. Once started, it usually holds prime with the pumps, it is just the initial start that it may have a "little" air in the system. Maybe even try restarting the engine a few seconds after turning the engine off, to see if it starts the same way or better, before losing prime, if it is even a prime issue.
 
RI Chevy Silveradoman said:
I was going to say fuel filter condition, and to check the injectors as well. :) All good info given!

Maybe a check of the oil to see if your getting any fuel contamination. Also, check the primer on top of the fuel filter. I won't say what it should be like. :rof: I would be leaning toward a fuel prime issue.

I would go ahead and check to see if there are any "hidden" codes that are stored and just not showing, if you can.
Click to expand...

Your thinking DMAX, this is a 6.5 he has. Theres no primer pump on the fuel filter for a 6.5, they have a frame mounted electric pump. For a 6.5 delayed starts are normally either a bad injection pump, or injectors. Injectors being the most common cause of delayed starts. Prime issues with a 6.5 will normally result in a start then stall condition. A good way to get an idea as to what it is to start it up and bring it up to temp. Shut it off and restart it within 5 seconds. If it fires right up then i would look at the injectors, if it still takes a few seconds then the pump may be getting a worn rotor head. This is dependant on wether or not the TDCO is set correctly so that the ECM is firing the fuel solonoid correctly.
 
have you checked the starter? My truck got brand new injectors, inj pump, and glowplugs last year and during the summer it still wouldnt start right up when it was hot. My starter finally died and when i replaced it the truck starts right up now with no glowplug cycle if it sits less than two hours.
 
I will see what RPM registers one start up on the ScanGauge. I'm hoping for maybe a timing issue? We are talking a van with the easy-to-access injection pump. If the PMD was replaced, I don't know/can't see if the pump was rotated at all to access it.

Now for the age old question of... what's the better deal? Buy the software and fumble through it myself or dealership-it for time? This is my bread and butter wagon now, so down time = no money being made. If the vote is for software, which is the "most liked" software for our dinosaur-diesels?

Thanks all for your input so far!
 
Carcode, not entirely user friendly but will do TDCOffset. There is a tutorial on doing the offset on here.

Autoengenuity, not sure if it will do TDCOffset, costs more as well.
 
Beings it's an 01, you will need bidirectional software to do the TDCO on it. For the 96-98 trucks you can get it up to temp and do the key/throttle pedal sequence and it will do it itself, but I found that 99+ doesn't do it always. And if you do take it to a shop, make sure they KNOW the 6.5. MOST diesel guys at the dealerships don't have a clue how to work on the 6.5, or what tdc offset even is.
 
Umm fuel pump working? My OPS was messing up n the fuel pump relay with priming button fixed my problem. Prime her n then crank her up. Dont know if u n mine works the same.
 
Oooops. Not a Duramax.

THEFERMANATOR said:
Your thinking DMAX, this is a 6.5 he has. Theres no primer pump on the fuel filter for a 6.5, they have a frame mounted electric pump. For a 6.5 delayed starts are normally either a bad injection pump, or injectors. Injectors being the most common cause of delayed starts. Prime issues with a 6.5 will normally result in a start then stall condition. A good way to get an idea as to what it is to start it up and bring it up to temp. Shut it off and restart it within 5 seconds. If it fires right up then i would look at the injectors, if it still takes a few seconds then the pump may be getting a worn rotor head. This is dependant on wether or not the TDCO is set correctly so that the ECM is firing the fuel solonoid correctly.
Click to expand...

Ooooooops. You're right Ferman. Sorry. :eek: I saw 2001 and thought he had an LB7. Sorry for the confusion.
 
Could those vans have navistar engines factory? Just a thought, not topic related at all... If it was me i would jump the LP and have it dead heading at start up and see if it starts better, thats bout the same as killing and resarting immediatly.
 
The lift pump runs during the WTS (wait to Start). It primes fine during that time. When the fuel filter was leaking originally, I had to drain the filter, and then I just primed it several times during the WTS.

Now, IIRC, gmctd and TurbineDoc had experimented around with the difference between OBD-I and OBD-II and found that the lift pump relay on the OBD-II was controlled by both the OPS and the ECM. If the ECM had a signal it was running (rpm) it would keep the lift pump relay on. But that has been years ago now. All I can remember about that was Tim asking JD about "where's all your data dude?" (talking about his OBD-I truck)

Those where the good ole days....
 
knkreb said:
The lift pump runs during the WTS (wait to Start). It primes fine during that time. When the fuel filter was leaking originally, I had to drain the filter, and then I just primed it several times during the WTS.

Now, IIRC, gmctd and TurbineDoc had experimented around with the difference between OBD-I and OBD-II and found that the lift pump relay on the OBD-II was controlled by both the OPS and the ECM. If the ECM had a signal it was running (rpm) it would keep the lift pump relay on. But that has been years ago now. All I can remember about that was Tim asking JD about "where's all your data dude?" (talking about his OBD-I truck)

Those where the good ole days....
Click to expand...

That does sound right. Since I dont have a properly running OBD2 truck I hadnt seen the LP run on WTS. On my OBD1 I used jumping the LP to eliminate losing prime causing hard starts.

Mine ended up being a combo of things, bad injectors and gp's, bad batteries, and corroded cables. once all those were fixed my IP got weak.
 
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