Truck is one-owner, 1998.5, 2 door, 5-speed, 2 x 4, limited slip differential, 3.5x rear axle ratio, 240,000 miles, exhaust replaced with MBRP 4" last year. Few problems in its history, and until now, never any performance problems. Truck was parked from mid-June through mid-July while I was on vacation. Upon return, truck was hard to start: turned over ok, but didn't fire right off. That problem has continued and gotten worse. I've driven truck about 700-800 miles since mid July, mostly on a trip of 500+ miles, and another trip of 100 miles. Not sure, but it seems truck is harder - much harder - to start after it is at normal running temperature. Otherwise, drive-ability, power, MPG seem normal, although MPG MIGHT be off 1-2 MPG.

Fuel filter is reasonably fresh. I was suspicious of lift-pump (original one still in place) so pulled output line from fuel filter and bumped starter. Pump ran for 26 seconds but NO fuel was pumped - repeated several times. Today I replaced the original lift pump with new/improved Airtex E7153, repeated the bump starter test. Fuel flow is clear of bubbles and meets the 45 ounce minimum. Reconnected line to VP44 and started truck. Starting was again hard, cracked a couple injectors to bleed system, got fuel flow, tightened injectors, and engine fired after a bit more cranking, and immediately settled down to a proper idle. I let it run for a couple minutes to observe and recharge the battery, turned the key off, and tried to restart engine after perhaps 10-15 seconds. It did not fire and after a short effort I decided to let it sit and seek advice here.

1) Is there any chance that anything other than the VP44 is bad? What tests should I run to be sure of the problem?

2) What source/options should I consider if I need a new VP44? Let me say, I care nothing about rip-roaring horse-power. I care about economy of operation - especially MPG. I often make trips to northern Canada hauling a slide in camper and trailer, typically driving at about 60 MPH on open highway to get good fuel mileage. Both fuel economy and driving range are important to me. In northern areas fuel can exceed $7.00 per gallon and be 300+ miles between refueling opportunities. Are there any other upgrades/mods I should consider with a focus on improving mileage without lessening power?

3) I have a 600 mile trip to make on Monday - South Carolina to Pennsylvania. I could postpone the drive to Tuesday. Can I expect the truck, once started, to complete this trip. I have another vehicle in PA and could do the VP44 swap there. Otherwise, I have an urgent need to complete the repair this weekend.

4) I plan on installing a fuel pressure gauge. I'm thinking an electric gauge in cab, either mounted on "A" pillar, or on steering column, with a sender that will screw directly into empty output side fitting (now plugged) on top of fuel filter housing is a good way to go - Westach seems to fill the bill and be readily available. I don't plan to add exhaust gas temp, boost, or other gauges, but will consider good reasons that I should add them to my plans.

Thanks in advance for all help/advice - Jim

 

It sounds to me that your VP44 has gone south. This is not that uncommon if your LP goes it can and will take the VP44 out with it. A stock replacement will work just fine for you, just make sure that you get a FP gauge so that if the LP goes out ever again you will find out before it takes your VP44 with it. I am sure that there is a vendor on here that can get you a VP44 by this weekend to swap it out over the weekend.

 

After sittin all that time the first thing I would try would be some good fuel additive to clean out the system. It may have gunked up on ya from sittin, the fuel may have gone bad also. For a quick cleaning I would recommend Sea Foam. Don't pour it in the tank, just change the fuel filter and fill the fuel canister with it before you put it back together. This way it's is completely cleaned out of the system within seconds. Cleans it all out and is gone before it has time to affect the seals in there.

If this doesn't help I would also pull the outgoing banjo bolt on the VP. This one is a fuel pressure regulator that may be sticking. Just push on the spring and make sure it still moves free and doesn't stick anyplace.

If you don't have fuel pressure guage on the truck where you can see it at all times, GET ONE INSTALLED ASAP. This is the single most important modification you can make to these trucks. The fuel pressure readings will also tell a lot about what the problem is here. They can be had for less then $50 for everything needed to install it and save you a grand plus for a new VP44 if your havin problems.

Welcome to the site.

 

I seriously don't think it's the VP. You don't have any symptoms of dead peddle or driveability issues either. Just the hard start problem.
You must install a gauge to see what the FP is! Go to your local auto parts store and get them to check for any codes.
Once you do these two things get back to us and we'll take it from there.
Oh ya how much fuel is in the tank?

 

I'll check that VP outlet side banjo fitting pressure regulating spring first - in the morning. That's the easiest/quickest thing I can do. As to the fuel being old/gunky - I'm open minded/hopeful it could be that simple, but the fuel that drained from filter and old lift pump all looked good, as did the fuel I pumped up out of the tank while checking the new lift pump, plus a half tank of fuel was bought about 300 miles ago, filling the tank. The tank is now just over half full.

There is an advance auto store I can walk to in morning to get the fuel additive/cleaner to try that idea after I look at the pressure regulating spring. I'll post after 'm done with those items.

Thanks - Jim

As to driveability: I drove through the West )by God) Virginia and Virginia mountains, (lightly loaded) and on down through NC and SC at 65-70 adn more MPH with no sign of any problems, and some short trips around here with never a sign of any power, idle or other driveability issues - just the hard starting problem.

 

I'm always lookin for the easiest tries first, we'll work our way to the harder stuff if they don't work. If they are still the stock fuel lines I would guess probably an air leak or two in the system also letting it lose prime while it's sittin and drawing air while runnin. When it's runnin it still get's enough fuel to compensate but when it it sittin the fule in the lines is being replaced with air making the hard start. The VP44 will be the last thing on the list since it's the most expensive and biggest pain in the back side.

 

With a none working LP it is only a matter of time now until th eVP dies. The hard start woul dmake a person believe that it is FP that is causing it... Check the regulator spring on the VP, put a good gauge on the truck to monitor FP and if it drops below 7lbs start thinking about another LP... One like an air dog or such. As far as a good VP FBD has a SO pump that works great and will not break the bank...

 

First thing this morning I pulled the outlet banjo bolt on the VP44. The ball/spring in it moved freely and easily.I manipulated it a bit to ensure it is working freely. Next, I got some Sea Foam liquid, drained fuel from filter canister (perfectly clear and free of water and all other sediment - filter had been changed about 4K miles ago), poured half the Sea Foam into the filter canister, tightened everything back, removed air hose between air filter and turbo inlet, cracked the front injector to help bleed any air, bumped starter to run lift pump to prime system, gave turbo shot of starting fluid. Engine started. I re-installed and re-tightened everything and drove short distance to Advance Auto, left engine running, had codes checked - there were no codes set, no "Engine Check" light showing. I then drove truck about 15 miles, parked mid-way and let it idle about 10 minutes to look for leaks (no leaks seen or heard), returned home, turned it off, waited about 20 minutes, tried to start engine in normal fashion and it did not start.

Somebody above suggested air leaking into the fuel system. After installing the new lift pump yesterday I ran the lift pump and observed the fuel coming from the fuel filter outlet - it took a couple bumps to purge air from the system, after which the fuel was free of air and flowed well. The fuel I drained today looked fine.

Jim

 

Some common issues for fueling problems here include some of the following, not in any particular order:

Sediment screen in the tank is clogging up. At the bottom of the pick up tube in the fuel tank is a screen that prevents sediment from being picked up, after some years or even just one tank of dirty fuel this screen can become clogged to the point of not allowing enough fuel through.

Pickup tube cracked. These pickup tubes have been known to crack and when your fuel level get's below a certain point it starts pulling air in through the crack much like if you put a hole in a straw and try to drink through it. It pulls the fuel through but mixes air in the with it.

Pin holes/air leaks in the fuel line. If these leaks are between the tank and the LP fuel may not come out of them to show a leak but air will be sucked in when the LP is pulling pressure. They are a bear to find. Much easier to just change the hose. This also allows fuel to flow back into the tank during shutdown so even though your LP is running for the seconds prior to start up it's not enough to get enough fuel back into the lines and primed. Fuel will remain in the filter canister but this leaves you with air pockets in the lines that can do funny things throughout the system.

A bad LP right out of the box. If your using the OEM LP as a replacement it's a common thing for them to be bad right out of the box. These things are junk, there's just no nice way to say it. Carter makes nice pumps for almost all applications but the pump for our trucks is a disgrace to their name.

Having the Pressure gauge will tell the tale on almost all of these problems and finding these problems early is the best way to not kill the VP. This is why it's so important to have the gauge. Just a cheap little needle style one, not the fancy digital ones. They aren't all that dependable. The dummy lights tell you if your system is broke, but don't tell you if your having problems so they are not suggested either. The pressure gauge tells you if your having pressure loss only at certain times, pressure spikes or if it is staying low all the time and all of this tells you what the problem may be.

 

First - thanks. Second, correct me if I'm wrong: I think it is none of the items on the list. There is no air in the fuel being pumped out of the fuel filter canister outlet. The lift pump (brand new - installed in effort to fix hard starting problem - old pump tested bad - new pump tests good) produces a good flow from the fuel filter canister outlet. There is no loss of power when driving - no fuel starvation - no power loss - as occurs when the fuel filter is past due to be changed so it is hard to picture there is any clogging/restriction in the fuel lines that make starting hard.

Yes, I understand and agree I should have installed a fuel pressure gauge long ago. I will do so soon. But the new lift pump - the latest upgraded Airtex E7153, pumps fuel at a good flow rate and free of air bubbles, and the problem changed not one whit after the installation of the new pump seems to indicate no fuel flow problems between the fuel tank and the inlet to the VP44. I understand that it seems likely that hard starting is caused by a fuel/air problem between the tank and the VP44 inlet, but the checks I've made, and vehicle performance when running seem to indicate no problems in this area. One thing I can try to reduce the vacuum in the line between the fuel tank and the lift-pump is fill the fuel tank - I'll try that this afternoon - beyond that I have no idea where else to look or what other tests to run.

Call me Stumped - Jim