I am seeking the wisdom of others before going paranoid! ):h

The Dmax has (all of sudden!) developed a surge in the idle. When idling, it "surges" about 50 rpm (blip on the tach) every 3-5 seconds. Acts like someone is "bumping" the accelerator. Only surges when below 1k rpms. Smooth at all other times, even with cruise set. Also, with no power adders, it will smoke when pegged from about 2k rpms to redline. I don't smell diesel in the oil, and level is ok (2k on oil). I can't say about the mileage since the new bed is heavier. Also, the power is good for stock.

P.S. I just picked up the Dmax after having my new bed custom built. It has been sitting for 16 days and only started 4 times, each for about 5 mins. I dropped it off with 3/8 of a tank. The filler has been relocated. I think it is probably something in the fuel. Last night I used it for a delivery and burned a tank of diesel with 3/4 quart of Power Service added. Surge still there this morning, but seems to be getting better. I will disconnect the battery at lunch so the "puter" can reset and plan on changing the fuel filters Saturday.

Thanks for listening! ):h :rolleyes: :D

Oops! I did not realize there was another thread similar. However, mine just started doing it, and does it in drive with the brake applied. Annoying at stoplights!

Sounds like a fuel pressure regulator to me. Mine does the same thing, surge at idle and lurching ahead in drive with brake applied.
Haven't tried pegging it from 2k to redline, but I would expect to see some smoke when hitting the pedal that hard.

Mine did the same thing shortly after changing the fuel filter. Turned out I had not bled enough of the air out. Did they happen to open up any of your fuel lines when doing the work on the bed? If so, you may have air in the system.

Sounds like a Fuel Pressure regulator to me also.The 01's had a weak spring in them and were replaced under warranty with a idle "lop" you describe.



If your still in the under 100K range have it warranted.

Thanks for the replies!

Seems that the battery reset, fuel additive, and bleed/ prime fuel system worked. Still there, but only slightly. I am adding it to my short list for my 35,000 mile warranty service (about a month away!).

Thanks again!