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6.5TD motorhome starting problem
- Thread starter Bezzer
- Start date
dbrannon79
I'm getting there!
what year is it? and what type of PCM connector does it have under the dash?
OBD1
OBD2
OBD1
OBD2
jrsavoie
Recruit
Install a toggle switch to run it whenever desired for diagnostics and priming
dbrannon79
I'm getting there!
for OBD2, you'll need to find the fuel pump relay under the hood and jumper pins 30 and 87. the pump should run iirc. for the older OBD1 systems there is a pin in the data connector you can apply positive power to and turn on the pump, that won't work for yours.
other than that, find the pump on the frame and disconnect it's connector, run a ground to the black wire and positive to the red wire on the pump connector. you can use a cordless drill battery to do this so long as it's a not a 20v battery. 12, 14, and 18v battery will work, just don't run it very long on an 18v battery.
other than that, find the pump on the frame and disconnect it's connector, run a ground to the black wire and positive to the red wire on the pump connector. you can use a cordless drill battery to do this so long as it's a not a 20v battery. 12, 14, and 18v battery will work, just don't run it very long on an 18v battery.
jrsavoie
Recruit
Some place handy when your working on.it.
On trucks, Suburbans I put it on the firewall right next to the underhood fuse box.
On the older vehicles, I put it by the load center. On the right side.
I'm not sure where I would put it on a motorhome. I use a safety toggle with the flip cover. I also use an inline fuse
Will L.
Well-Known Member
Usually people put a toggle switch somewhere close to the fuel filter because that’s where you use it most often. Install new filter, turn on switch until full and air bled out. Then turn off.
GM testing procedure calls for one pint every 15 seconds. The computer controlling the run time without oil pressure is why they set it that way.
In that time you should have a minimum of one pint.
Before the computers controlling it the instructions were running a jumper wire and filling up a 1 quart container that was made of glass and sealing it off to leave for settling test over the next hour for minor problems and overnight for major ones. Filling this 1 quart container the dealership had was supposed to take 30 seconds maximum.
Your lift pump is not producing the proper volume. It is not producing the proper pressure. It needs replacing.
We determined the hard start was heat related by use of the block heater. However continued operation of a weak lift pump will wear out the injection pump faster. So consider which is more critical for your use and address them both.
Either cycle the key 3 times before starting for the glow plug warming time or get the bolt on relay kit from Leroy Diesel and use a switch/ button to operate it. O one makes a kit with a timer -either people want to save money and diy or they want it to be automatic and send their ecm in for a reprogram extending glow time.
As to replacing the lift pump- your budget and use become the question.
Best thing out there is to use a Fass system including their filters and their fuel heater. Completely eliminating the GM ffm (fuel filter assembly). You sell the old on on ebay or here to recover a couple bucks.
At the same time if doing everything you can tor improvement- you could seap the fittings going into the ip for 3/8 instead of 5/16, however being fed from the FASS pump, I would run it in the larger size and reduce at the ip.
Next step down is keep factory filter system but install just the Fass pump without the filters.
Beyond that is cheaper and cheaper lift pumps as you go. But understand the cheaper ones live shorter lives and make the system struggle more.
In a pickup where the resale value is $5000, it’s hard to justify several hundred into the fuel system to eliminate future problems and extend life of the ip which is about $1,000 for parts.
In an RV, if you dont replace the ip yourself- labor costs often roll into the thousands. Same scenario for Hummers like mine. Labor often more than triple the cost of the parts. And resale value in hummers or rv makes dropping $1,000 into a new fuel system acceptable.
We can’t say which lift pump is stock for yours- have to post pictures to see.
Most common is the inline pumps and the best of those is the AC Delco EP158. But even brand new they barely hit minimum specifications, usually before year 2 is up they fall below spec.
GM testing procedure calls for one pint every 15 seconds. The computer controlling the run time without oil pressure is why they set it that way.
In that time you should have a minimum of one pint.
Before the computers controlling it the instructions were running a jumper wire and filling up a 1 quart container that was made of glass and sealing it off to leave for settling test over the next hour for minor problems and overnight for major ones. Filling this 1 quart container the dealership had was supposed to take 30 seconds maximum.
Your lift pump is not producing the proper volume. It is not producing the proper pressure. It needs replacing.
We determined the hard start was heat related by use of the block heater. However continued operation of a weak lift pump will wear out the injection pump faster. So consider which is more critical for your use and address them both.
Either cycle the key 3 times before starting for the glow plug warming time or get the bolt on relay kit from Leroy Diesel and use a switch/ button to operate it. O one makes a kit with a timer -either people want to save money and diy or they want it to be automatic and send their ecm in for a reprogram extending glow time.
As to replacing the lift pump- your budget and use become the question.
Best thing out there is to use a Fass system including their filters and their fuel heater. Completely eliminating the GM ffm (fuel filter assembly). You sell the old on on ebay or here to recover a couple bucks.
At the same time if doing everything you can tor improvement- you could seap the fittings going into the ip for 3/8 instead of 5/16, however being fed from the FASS pump, I would run it in the larger size and reduce at the ip.
Next step down is keep factory filter system but install just the Fass pump without the filters.
Beyond that is cheaper and cheaper lift pumps as you go. But understand the cheaper ones live shorter lives and make the system struggle more.
In a pickup where the resale value is $5000, it’s hard to justify several hundred into the fuel system to eliminate future problems and extend life of the ip which is about $1,000 for parts.
In an RV, if you dont replace the ip yourself- labor costs often roll into the thousands. Same scenario for Hummers like mine. Labor often more than triple the cost of the parts. And resale value in hummers or rv makes dropping $1,000 into a new fuel system acceptable.
We can’t say which lift pump is stock for yours- have to post pictures to see.
Most common is the inline pumps and the best of those is the AC Delco EP158. But even brand new they barely hit minimum specifications, usually before year 2 is up they fall below spec.
MrMarty51
Well-Known Member
I got that Air Dog system and I am happy that I jumped on that.
Finally got the two FP sending units functioning and now I’m even happier.
That shstem is well worth the cost and the effort to install it.
Finally got the two FP sending units functioning and now I’m even happier.
That shstem is well worth the cost and the effort to install it.
Will L. and dbrannon79 and everybody : I ordered the 15/16 inline fitting with id 1/8" NPT Port today.
Also would like your opinion of this AutoBest Fuel Pump (lift pump) - same as it came originally on my motorhome- but flows 15% more. I attached picture. Haven't ordered it yet. Thanks !
Info: Autobest High Flow Fuel Pumps are direct fit OEM pump replacements, so there are zero modifications required. If your vehicle has horsepower upgrades installed, your stock pump may not provide sufficient fuel to meet the increased performance demands. To combat this, Autobest's team of engineers have specially redesigned the stock pump so that it has an increase of up to 15% in FLOW RATE; now giving you the option to support your invested modifications with a boosted fuel flow rate.
Ideal to support existing modifications, such as:
Air Intake System
Larger Fuel Injectors
Exhaust Headers
Phenolic Spaces
Free Flow Exhaust
Sport Tuned ECM/ECU
High Flow Air Filter
Throttle Body Change
Also would like your opinion of this AutoBest Fuel Pump (lift pump) - same as it came originally on my motorhome- but flows 15% more. I attached picture. Haven't ordered it yet. Thanks !
Info: Autobest High Flow Fuel Pumps are direct fit OEM pump replacements, so there are zero modifications required. If your vehicle has horsepower upgrades installed, your stock pump may not provide sufficient fuel to meet the increased performance demands. To combat this, Autobest's team of engineers have specially redesigned the stock pump so that it has an increase of up to 15% in FLOW RATE; now giving you the option to support your invested modifications with a boosted fuel flow rate.
Ideal to support existing modifications, such as:
Air Intake System
Larger Fuel Injectors
Exhaust Headers
Phenolic Spaces
Free Flow Exhaust
Sport Tuned ECM/ECU
High Flow Air Filter
Throttle Body Change
Attachments
dbrannon79
I'm getting there!
I looked up this pump and it's a replacement for the AC Delco EP309 if someone can lookup what the rated pressure and flow rate is for the EP309 we can get an idea on what this pump is supposed to be capable of. Now with that said, purchasing it from RA, good luck with warranty exchange. and for the price. order two and keep one in the glove box with a couple of wrenches for when it dies on the road!
dbrannon79
I'm getting there!
is this the one? F2310? look at the specs. @Will L. IDK about this. that looks like a diaphragm type pump to me, it says it's a vane pump.
Big T
Well-Known Member
FASS, Raptor, or go home.
Sorry! The part I ordered is 5/16 - not 15/16.
*******************************************
You can check this page below for the info you wanted about the pump
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You can check this page below for the info you wanted about the pump
dbrannon79
I'm getting there!
Here are the specs for the EP309 and the EP158. if you go with a factory style lift pump, go with the EP158. it's the better of the factory pumps.
Take note of the max and min pressure and flow rates. TBH our rigs need something that will flow at least 50gph for it to keep up with the fuel demand under load.
Take note of the max and min pressure and flow rates. TBH our rigs need something that will flow at least 50gph for it to keep up with the fuel demand under load.
Will L.
Well-Known Member
So the spec shown shows the EP158 as a max pressure of 14psi.
That is the one myself and many others have been recommending as the best version of this POOR design.
I’d bet there is many people here that ran the EP158 and I also bet there is not two who said it held 14 psi for more than 4 hours.
And the other one is a lesser pump from the start.
If you stick with the low cost inline pump- get the AC Delco EP158.
Then in a year to a year and a half get another one. Then another one.
Then another one.
I lucked out and had a place that was replacing them under warranty without a major fight. After a while it ended. And my db2 ip only needed 5psi so it wasn’t as bad as you ds4 guys.
That is the one myself and many others have been recommending as the best version of this POOR design.
I’d bet there is many people here that ran the EP158 and I also bet there is not two who said it held 14 psi for more than 4 hours.
And the other one is a lesser pump from the start.
If you stick with the low cost inline pump- get the AC Delco EP158.
Then in a year to a year and a half get another one. Then another one.
Then another one.
I lucked out and had a place that was replacing them under warranty without a major fight. After a while it ended. And my db2 ip only needed 5psi so it wasn’t as bad as you ds4 guys.
Thanks dbrannon79 for the specs on the two pumps. Now that I know I have a DS4 injection pump and the original lift pump has lasted 29 years.
I have no idea what lift pump is on my Chevy P30 chassis. The lift pump part number is facing the frame- so I can't see it till I remove it.
Looking at it - it seems to be the same size as the EP309 or the EP158.
As soon as my part -( 5/16 inline fitting with id 1/8" NPT Port) -comes - I will start checking my one quart fuel timing by the seconds....and the fuel pressure at the injection pump.
I plan on connecting the pressure gauge on the inline fitting before I check the one quart flow. Then shortening the 5/16th hose and install it on the injection fitting and checking the fuel pressure.
Does that sound reasonable?
Thanks Will L, I know what you are saying but after 29 years whatever that origninal lift pump is- I can't wait to see the hidden part number.
*****************
By the way - my injection pump was replaced 25,000 miles ago under a recall.
I have no idea what lift pump is on my Chevy P30 chassis. The lift pump part number is facing the frame- so I can't see it till I remove it.
Looking at it - it seems to be the same size as the EP309 or the EP158.
As soon as my part -( 5/16 inline fitting with id 1/8" NPT Port) -comes - I will start checking my one quart fuel timing by the seconds....and the fuel pressure at the injection pump.
I plan on connecting the pressure gauge on the inline fitting before I check the one quart flow. Then shortening the 5/16th hose and install it on the injection fitting and checking the fuel pressure.
Does that sound reasonable?
Thanks Will L, I know what you are saying but after 29 years whatever that origninal lift pump is- I can't wait to see the hidden part number.
*****************
By the way - my injection pump was replaced 25,000 miles ago under a recall.
Back to everybody! Test #1 -After 15 seconds with key on- pump turns off....see quart picture attached showing close to 1/2 qt of diesel....double that and you'd probably get around 30 seconds.
Also removed wire connector from oil pressure switch - still turns off at 15 seconds. Please remember this is a "drive by wire" and fuel pressure should be 8 to 14 lbs.
Test #2- Reconnected fuel pressure gauge back to injection pump...turned key on- 5 1/2 lbs. instantly.
These are the two tests you wanted me to do. What's your thoughts on this?
Also removed wire connector from oil pressure switch - still turns off at 15 seconds. Please remember this is a "drive by wire" and fuel pressure should be 8 to 14 lbs.
Test #2- Reconnected fuel pressure gauge back to injection pump...turned key on- 5 1/2 lbs. instantly.
These are the two tests you wanted me to do. What's your thoughts on this?
Attachments
Will L.
Well-Known Member
Ok- the lift pump isn’t doing the greatest, but should not in any way be a problem.
You measured the pressure AT THE INJECTION PUMP INLET, right?
Anywhere else is invalid for the diagnostics.
Let that fuel settle for a day and examine it. Looking for any contamination to settle out on the bottom of the container.
You measured the pressure AT THE INJECTION PUMP INLET, right?
Anywhere else is invalid for the diagnostics.
Let that fuel settle for a day and examine it. Looking for any contamination to settle out on the bottom of the container.
I'll let the fuel settle till tomorrow.
You've sent me the picture I attached showing the blue cap on the injection pump . The other picture shows my set up and dbrannon79 red circled spot that I removed off my injection pump. Then connected my pressure gauge to that hose and then connected the pressure gauge back to the injection pump.
Why am I not getting the 8 to 14 lbs that's required for the DS4 that I have?
You've sent me the picture I attached showing the blue cap on the injection pump . The other picture shows my set up and dbrannon79 red circled spot that I removed off my injection pump. Then connected my pressure gauge to that hose and then connected the pressure gauge back to the injection pump.
Why am I not getting the 8 to 14 lbs that's required for the DS4 that I have?
Attachments
dbrannon79
I'm getting there!
chances are your lift pump is weak or it has one that's only rated for 5psi. I would plan to replace it with a Delco EP158. you can look at your pump and see if there is a tag on it with a part number still.
If you extend your gauge so that you can watch it while driving, see what your pressure does under load when you accelerate. you don't want to see the gauge fall to zero under load at any time. as long as it maintains at minimum 1psi under full load you'll be ok
If you extend your gauge so that you can watch it while driving, see what your pressure does under load when you accelerate. you don't want to see the gauge fall to zero under load at any time. as long as it maintains at minimum 1psi under full load you'll be ok