2001 150 Vmax HPDI at idle, then quits and won't re-start

Calling all mechanics. I think this is a relatively easy to solve issue, and may have been covered in other posts, but I appreciate any replies to help me narrow down the issue with a little more certainty. 2001 Vmax 150 HPDI that has provided me with years of trouble free service. I change filters regularly (external water separator - twice a year, internal in clear cannister - once a year, just changed out the VST in the early summer). I have had the following issue happen to me 3 times over the last few months. After running at idle for about 15 minutes (yesterday I was running it on the muffs on the trailer), motor simply shuts off. Usually if I restart it right away, and throttle up and run home, all is well. But since it was on the trailer, that obviously was not an option. On two previous occasions, restarted the motor, throttled up, and ran 20 - 40 minutes home with no further incident.

Yesterday, the motor restarted, but died. Then would not fire at all. Turns over, just won't start. Pulled the plugs and they didnt look so hot. So I replaced them, but it would not re-start.

Things I haven't done - I've not replaced the inline filter (I think it is the medium pressure filter), nor have I cleaned the O2 sensor in some time. I did replace the Big Blue external filter yesterday before the incident. I looked at the fuel that I dumped from the filter and it did have a few flakes of trash, but nothing extraordinary. Motor seems to be getting fuel as the fuel cylinder under the cowling is about 3/4 full.

Any thoughts would be greatly appreciated.

Richard

Re: 2001 150 Vmax HPDI at idle, then quits and won't re-start

Check fuel pressures and then spark to see what is going on

Re: 2001 150 Vmax HPDI at idle, then quits and won't re-start

You certainly need to pull the o2 sensor and clean if it hasn't been in 2 years....no doubt about that...clean by burning off with torch...no chemicals/solvents....also I would check or just replace the pump ball on fuel line...would be surprised if you had a fuel pressure problem as it runs perfect(yes?) at anything above idle...opposite of fuel pressure problems. Clean the o2 and change the filter you haven't and i think you may be pleased.

Re: 2001 150 Vmax HPDI at idle, then quits and won't re-start

When your starting engine are you advancing the throttle? Cylinders 2 and 3 do not fire while the engine is in neutral if you advance the throttle more in an attempt to start other cylinders will not fire to prevent overreving. Sounds more like a fuel restriction you can verify this by draining the VST and putting the fuel into a gradutated cylinder when you experience the problem and then prime the bulb until it is firm and drain again. If you have more fuel in the VST from when you primed the bulb you have a fuel restriction. Also keep in mind that the low pressure fuel pumps torn diaphrams can also cause your problems. I would just go ahead and replace those first. Also your plugs will look fouled at a low rpm, once you reach the upper rpms is when you should pull them. Also disagree on the O2 sensor.

Re: 2001 150 Vmax HPDI at idle, then quits and won't re-start

Here is what we found - slight air leak at external fuel/water separator filter was causing fuel pickup issue. Very little fuel pressure in the vst tank. Replaced a section of fuel hose between the bulb and filter bracket, new fuel bulb, and tightened up the fuel filter a little. At that point we could no longer hear any hissing when squeezing the bulb.

Started right up after that, and ran it on the muffs for about 25 minutes. Planning to go ahead and replace the medium pressure filter, clean up the O2 sensor, and replace the high pressure fuel pump oil next week. Life is good now!

Merry Christmas to all.