Ok, so I bought this 1999 Durango yesterday. 167k miles, no codes. They thought there was something wrong with the fuel filter because the RPMs were jump and it liked to hesistate while driving. So I managed to get it for $1500. Threw a TPS on it, good to go, no more jumpy RPMs no more hesistation when driving.

Now the only issues I am having, is when I go to accelerate from a complete stop. The truck will drop RPMs (from 600-700 to about 400-500) I am thinking either MAFS, Throttle Body needing to be cleaned, Plugs Replaced? Anyone have any ideas?

 

The RPMs actually drop initially, when you put your foot on the pedal? Is this correct? And if so, is it only when in gear, or does it do the same in park, at idle?

 

The RPMs drop when I have it in gear and initially hit the accelerator, as well as in park, usually not so much in park, but it does do it in park.

 

Tune up, we just went through this with my mom's 99 tahoe 350 vortech. Sounds like the cap and rotor. I would do all the things you listed to since you just bought it. Plugs (champion coppers gapped @.040), wires (mopar performance or msd), cap and rotor (napa enchlin seems to be the preferred, get brass contacts on the cap), and a good throttle body cleaning (link in the DIY thread).

BTW, the 5.9/5.2 dont have a MAFS. HTH

 

Haha, of course they don't, New to the dodge family, always wanted one, and now I do, I will do a good cleaning of the throttle body and a tune up, and a fluid exhange on the transmissiona as well as change the filter. Thanks!

 

ok just put 2 and 2 together, and figured out something new. With the truck came an aftermarket radio/dvd in dash (one of the flip ups). I had been having a little issue with it for the past day, where the radio would turn off and not want to come back on. I noticed this evening, when I press on the accelerator, IF it dips down, the radio goes off! Don't know, maybe something electrical?

 

Check your battery connections and have your battery load tested. Really sounds like a bad connection. HTH

 

Yep, that'd be my guess, too, considering the added info.

Or +1, as you guys here say

Stixx, it's normal for the RPM to drop a little when you have it in gear with the brake on, but your DVD going off...that definitely makes it sound like an electrical problem, and the hesitation indicates that the ignition is probably getting low voltage when it happens. Since it seems to run fine at higher RPM (I'm sure you'd have said something if it didn't), then the problem appears to only happens when the alternator isn't turning fast enough to easily carry the system load, which points to either a connection problem somewhere, or a bad battery, or maybe both (possible, but less likely). Since you haven't said anything about starting problems, Adukart is probably dead-on with the connection problem theory. With all the electronics, ignition, fuel delivery system, etc. these things use quite a bit of power, and if there's a narrow pathway (bad connection) then everything that needs power will suffer somewhat.

I went into a little depth because if you're anything like me, you like to "learn to fish" (in the biblical sense, not literally) when you have a problem arise. That is to say, I thought you might want to know the "why" behind the "how". That, and because, when I have a few glasses of Rye (yes, I actually drink rye whiskey...that, or Bushmills) I get a little wordy

If you want to test Adukart's theory, before you clean your battery terminals, start your engine, turn all the lights on (inside and out), your radio, rear defrogger, emergency flashers, and anything else you can think of, and then hold the brake and slip it into gear (do this in your driveway, not at a stoplight) and see what happens. I'm guessing it'll kill your engine.

 

+2

I had the the radio shutting off and RPM drop/stalling the other day if I didn't keep my foot on the gas at all times. Turned out I had a loose battery terminal. I tightened it and all was good. About two years ago I had the same problem and it ended up being because of corrosion on the wires where they connect to the terminals and the battery post. I took the terminals off and cleaned all of the corrosion off the wires with a wire brush and then put on new terminals, which solved the problem. I also changed the battery that same week.

So definitely check your battery and wires thoroughly

 

Well see, the only time the RPMs drop is when I go to accelerate from a complete stop, it will sit and idle all day long at 700 RPMs with no problem. Doesn't always drop the RPMs when I am accelerating from a complete stop, usually when it is warm. I am going to check the connections and everything tonight.

On the connections part (I see you guys always talk about checking the battery first.) I will definitely agree with that. I have a 1989 Ford Ranger as well with 300k miles (thats why I bought this durango :-) ) It had a problem where if it rained it wouldn't start and if it did start, it would die when I hit the gas. Replaced the terminals and viola, fixed. So I will check that out tonight!