Ok, so I have an '04 D with the 5.7L powertrain 4x4 with almost 193K on it. Today out of nowhere, the engine stalled on me. Was coming to a stop at a stop light when this happened. I put it in park and tried to restart it. No success. Now the starter was trying to crank the engine, and it sounded like it wanted to start. Well got myself towed off the road and brought it to the shop. The check engine light did come on during all of this, so they hooked it up and were unable to pull any codes. The truck will start and will continue to run if applying gas during the starting process and continuing to give it gas once it is started. Now once you let go of the gas it will not idle and dies. The shop has also performed a fuel pressure check, and have stated that it checked out just fine, so not likely the fuel pump. They also removed the intake housing from the throttle body to see if that was plugged and the engine just wasn't getting enough air. Checked out fine. They then said that they believed it to be a plugged converter so towed me over to a muffler shop in town to check the cats. They haven't been able to get to it yet, so won't know more for at least another hour or two.

Please take into consideration that last Thursday and Friday I removed my exhaust manifolds due to broken studs on the rear of both manifolds and replaced the bolts, studs, and gaskets. So no more exhaust leak there. Maybe this could be a cause to my problem.

Now I have a couple of questions, if it is a plugged cat, they guy at the shop has suggested that he can just cut them out and pipe it (keep in mind I am in Arkansas at the moment and they do not have emissions rules here). Now I know that I have asked in the past what effects this will have on the vehicle, and I have gotten a nice variety of answers from earth hugging to you will throw codes. Outside the obvious of I should just replace the cats because they were there to begin with, or that I will throw an engine code because the o2 sensors will be reading the same temperature forward and aft, I would like an honest idea of what may go wrong if removed completely. Please spare me the ethics behind remove the cats as that is not what I'm looking for. So I will reiterate, I want to know, what harm can I do to the engine if the cats are removed and piped?

This is due to the fact that I am not currently home and in Arkansas at the moment and need to be in California Wednesday. I do not have days to waste trying to procure a new Y pipe with cats. So if removing them will do nothing more than make the truck louder, spew more exhaust gases, increase horse and torque, improve fuel economy, or throw a code because the o2 sensors are reading the same temperature forward and aft of the removed cats, then this will be my speediest option. If it will cause damage to my engine then I will spend the days here until I can get a new y pipe with cats.

Any input is greatly appreciated, and I apologize if I may sound rude in this post, but I don't need or want a lesson on earth hugging and ethics as I have already received this from earlier posts.

Thanks much.

~fr0gster

 

Frog:

Before you throw a bunch of money out here, get your battery load tested ASAP!!!

These are classic symptoms of a dying battery. Being an 04, if yours is OEM it is time for a new one just on age alone.

Don

 

Don, thanks for the reply, the battery has not been load tested yet thats I know of, but is only 14 months old and is not a cheapo. Unfortunately I ended up spending a night in AR last night *** the dealer couldn't look athw it til this morning.

Talked to my regular mechanic last night and he seems to think its is possibly the idle air control motor.

Update to post:

The cats are off and a pipe in between to replace the empty space. They were bad. One tested at 10 lbs, and the other at 8.5. They should test no more than 1.5.

 

Frog:

What kind of test did they perform on them? Although cats do sometimes go bad, usually it is due to an issue with engine such as running too rich.

With them removed, is it running better now?

As I understand it, putting a vacuum gauge on the engine and running up the rpms while watching will tell the story.

If the engine vacuum gauge begins to drop and stay down as rpms are increased, and exhaust restriction is indicated.

If the removal of them does not cure it. I say look back at the fuel pump. They can show good pressure at idle, then not be up to snuff when you are working the engine.

Don

 

Don,

Thanks again for replying. With the cats removed at first, still wouldn't idle. The non dealer shops were at a loss and didn't know what else could possibly be wrong, so finally buckled down and took it to the dealer.

The dealer inspected it and found that my plugs were fouled (should have checked this myself) and that the throttle body, idle air control (not serviceable on the 5.7 as it is built into the throttle body housing) were gunked up. They wanted to charge me close to 500+ bucks to clean the throttle body and perform a tuneup (replace the damn plugs). I told them to kiss off on the plugs but to go ahead and clean the throttle body. Once they had the throttle body and IAC cleaned up, truck idled fine. Paid them their 180 bucks and then took it to the parts store for some new plugs. They were kind enough to let me use their parking lot to change the plugs myself there. Took me bout two hours. I felt like a pro as every other time I have changed the damn things it has taken me at least three to four hours.

My guess as to why the plugs that were in it fouled up like they did is one they were the bosch plat +2s (only had 50 to 60k on them, replaced with champion coppers), two that I had ignored the exhaust leak out the manifolds forever (and since I fixed that problem last week, the tuck just couldn't breath), and three that the cats were shot. I don't know the name of the test that was performed, but the guy drilled a hole in them and then stuck some sort of pressure gauge in them to test em.

After all this was done, I went back to the muffler shop and had the guy rework my exhaust with a magnaflow muffler, and new pipe. The muffler that I had on it had some creaces in it , that he had showed me yesterday and advised that it was gonna rupture likely in two to three months. Now the sound of the magnaflow is nice, but a little loud getting started. Once on the freeway at crusing speeds, it isn't bad. Can here oneself think, talk on the phone, and listen to the radio without troubles. The only one concern that I really have about the exhaust now is that it makes a blurbbbbbbbb noise at shift points if shifting at about 2200 rpm or so. Kinda annoying and louder than I would like. Seem to think that I'm going to draw some unwanted attention to myself. Now I know that the original stock exhaust had a muffler in the center, and then the big ol tailpipe in the rear. Well no big ol tail pipe in the rear any more as that was killed long ago when I hung the exhaust up. But did have two mufflers on it before all this rework and was as quiet as could be even with the cats removed. idk gonna have a shop look at it again when I get a chance to see if I should add a second muffler or if there is something else they can do to quiet the shift points.

I really don't think my fuel pump is bad, as I haven't had any trouble with it since doing what I've done.

Anyways, the truck is running great (got out of AR about 500 bones lighter). Just put about another 400 miles on it today rolling it over to 193,4xx. Fuel economy is astounding. I currently have an empty tandem axle boat trailer behind me that weighs less than 2k lbs and am getting close to 15.5 mpg. I used to get somewhere between 9 and 12. That is also a combination of city, slow highway speeds (55, 60 mph) and fast highway speeds (75) and some hilly, windy roads.

Oh, I put a can of that bg 44k in the first gas tank leaving AR. I think that a lot of my carbon issues could also be related to this garbage fuel at the pumps these days (ethanol/unleaded mix) and that I put 87 grade in most the time. I have read that 89 is recommended, but it can tolerate 87. In states with higher elevation you can get as low as 85 and as high as I think 91....idk never pay attention to the super stuff as I like to pinch my pennies at the pump.

Also, I'm going to replace the throttle body when I get back home (whenever that may be) with one that has been bored out a little more. Price is about the same as buying a new one from the dealer. So why not, right? Wished I had the money to put headers on it when I replaced the manifold studs, bolts, and gaskets. Oh well.

Sorry if this reply seems all over the place. Been an extremely long day, and winding down on the net for a bit before going to sleep. Any comments you want to make about my post are welcome as I like kicking ideas around with people.

Well good night (or good morning).

~Fr0gster

 

You may need to tune the Durango if you get a larger diameter throttle body or atleast I had to when mine was installed,
FF

 

How do you like your throttle body? What tuner are you using? Do you like the tuner your using? Does it have a good amount of options? Can it handle shift point changes or can it only manipulate the engine?

I have talked with hemifever about the sct package that he offers. Have been thinking about going that route for a little time now, but really in the end I'm so concerned I'm goin to screw up my pcm and really don't want the bill it takes to replace one of those. Hemifever did mention that if the canned tunes that he sells with the sct tuner don't seem to be gettin the job done that for like 100 bucks he would line by line tune it. I like the idea of being able to work with someone 1 to 1 regarding the tune process, as I'm completely loss when it comes to that.

Do you have headers on your exhaust? Do you like them? Much performance increase for the cost?

***Edit***

Silly me should have looked under your post for what you have on your D.

Thanks,

~Fr0gster

 

Check out www.shophemi.com or www.inertiamotorsports.com ,
FF