03 V10 Rough Idle - Diesel Forum

03F250 · 12-09-2002, 05:09 PM

Hi fellow gassers.. I know some of you members recently got new V10's so I'am turning to you guys with new V10's for some help. My 03 V10 has a shudder at Idle. When I picked it up last weekend she ran fine didn't even know she was running. I put the AFE magnum kit on at 639 miles. I then filled her up with premium gas and thats when I noticed the shudder and shake of the engine at Idle. Otherwise truck runs great. Its just at Idle and even when coasting to a stop seems like a surging of the engine until completely stopped. The tach does jump up and down a little in neutral between 750-800 and in gear between 650-700 is this about right for the rpm's. I don't think the AFE intake kit would have caused this. And yes I disconnected the battery after installation to reset computer. I think the ultra 94 octane is the culprit. I will wait till I use up this tank of gas and go back to 87 octane. I hope thats the problem any other suggestions would be appreciated. Anybody else have this problem [img]/ubbthreads/images/graemlins/shrug.gif[/img] Thanks Dennis......

HeavyAssault · 12-09-2002, 05:12 PM

Yes I would have to say the gas may be the primary culprit.

Most chips or programmers require the use of 93 octane.
Go back to 87, it should go away.

03F250 · 12-09-2002, 05:22 PM

Thanks Heavy Assault.. But I was always under the assumption that higher octane was better. Also do you know what the rpm's are for an 03 v10 in neutral and in gear. Thanks again Dennis.... By the way how far are you from oak ridge thats where I bought my truck really nice people down there in T.N...

HeavyAssault · 12-09-2002, 05:45 PM

You drove a long way just to buy a truck!! [img]/ubbthreads/images/graemlins/eek.gif[/img]

I live above Nashville to the West a little at the Kentucky line.

I cannot explain the difference.
It has to do with the ECU monitioring the engine. I suspect it is based on how clean the fuel may burn. If there needs to be a certian level of CO2 in the exhaust and 93 burns below that level then there could be a dumping of fuel by the ECU to get to that higher level need for smooth operation.

I really can't say but from reading other sources I'm making my own guess.

I know that by using a chip/programmer you need 93. So what is changed when using a chip?? Fuel/timing curves by the companies.
So how does this effect your engine?? Remember the basic concept of an engine, then through in a computer and it gets really complicated..
If you are measuring certian aspects of engine output and have a means to change certian inputs, the need to use the proper fuel comes around. A fuel that burns dirty has certian levels of chemicals, and vice versa. If these are out of limit it may overwork the ECU to cause a rough idle while trying to fix the "problem" with the measurements of the out going chemicals.

monsta · 12-09-2002, 05:57 PM

Although the culprit could be the fuel it could also very well be the AFE. There are reports that the oils flung off from a NEW (or recently re-oiled) oil impregnated filter can coat the MAF sensor wire and give you symptoms like you describe.

A quick check of that wire will tell. If you clean it just be careful. Use a Q-tips and some alcohol and be careful not to break it.

Higher octane doesn't imply higher quality. In simple terms, the higher the octane, the lower the chances of the fuel self-igniting. This is important in a chipped truck since the timing is advanced.

03F250 · 12-09-2002, 06:57 PM

Thanks again Heavy Assault, Monsta... Well next fillup is going to be 87 and see what happens. I will pull the filter off tomorrow and have a looksy at the MAF. I guess if these remedys don't fix it I will have to put the stock air cleaner back on and see what happens. Otherwise I'am very happy with my truck. Big difference since my last truck was an 02 lightning. And I already have the mods coming Banks headers undecided about there cat back as I kinda like magnaflows. And I'am waiting for the superchip microtuner to come out for the 03's. Bedrug also on order for christmas present from my parents. I can see this truck is going to be a never ending project. There is always something else to get. Well I will keep you posted on the remedys. Thanks again for yor help. Dennis.....P.S. Heavy Assault yea it was a long trip did it nonstop but well worth it. I have never been treated better than I was by the dealer in Oak Ridge. This was my second truck bought from him. My truck was ordered on oct 30 delivered to dealership nov 16. [img]/ubbthreads/images/graemlins/eek.gif[/img] I really like the TN hospitality. My salesman invited me down to do some fishing on his boat next summer. I think I just might take him up on it.

HeavyAssault · 12-09-2002, 09:30 PM

That's cool. You can't beat good service, and it is worth the drive to be treated right.

BTW welcome to the wonderful world of never ending upgrades and mods!!

I have a sheet of stuff to do a mile long. Just do a little at a time, it helps to stay sane. [img]/ubbthreads/images/graemlins/biggrin.gif[/img]

dcd · 12-15-2002, 01:20 AM

I just bought a 2003 Explorer recently with the 4.6L V8 and I remember reading in the manual that using octane higher than 87 might cause rough idle or something to that effect. So maybe that is the culprit.