Hi,
I hope somebody might be able and willing to help me. I have a 2001 Dodge Ram 1500 Sport 4WD 5.9L. A little over a week ago it started missing real bad. It was a very sudden and hard miss, sometimes backfiring. Within a day of driving it, it became very severe until it quit running altogether. I made an appointment at the shop and ordered a fuel pump just in case, but it didn't really seem to me like a fuel pump issue based on the way it was acting.

I should clarify...I am not mechanically inclined. I finally got it into a shop the other day. They checked the fuel pressure with the key on and running (just idling). The fuel pressure was normal (within specs), so that ruled out the fuel pump. They replaced the distributor and rotary button, and that had no affect. The plugs and wires were replaced last year and they didn't appear to have a problem. They cut out the catalytic converter and checked it, and it was fine (they had fun welding it back in). They hooked up a scanner to the computer, and initially they thought it might have a bad fuel pressure sensor. They replaced the sensor and that had no affect.

The truck will idle just fine. It's when you give it the gas, even a little bit, that it starts missing terribly and backfiring. They noticed when they hooked up the scanner to the computer that initially the computer is giving them all the diagnostic readings (there was no code at all on the computer). However, when they give it the gas with the scanner hooked up, the scanner instantly goes blank and says something like "No Hookup Detected"....as if it's not even hooked up to the computer at all. It does this every time they give it the gas.

Based on this, they think the computer is bad and needs to be replaced. So I am about to order a new computer and have it pre-programmed to my truck. My computer part number is P56040273AF, and the S/N is TEH14112V9NQ. I am just wondering if anyone is aware of anything else that might cause this problem before I spend the money for a new computer, the time waiting for it to arrive, and the time waiting for another appointment in the shop. I really need this truck fixed as soon as possible, and if they replace the computer and that's not the problem, then we are back at square one trying to figure it out.

They worked on the truck for 7 hours the other day trying to figure it out, and this is going to end up being quite expensive any way I go about it.

Thanks for any advice.

Anthony

 

Wow they are really cleaning you out. That's why I'm real careful bout getting my vehicles worked on at shops because they have no idea about what's wrong with it and throw parts at it hoping one will fix the problem, or laughing that you are paying for every part they throw at and paying their paycheck for horrible service.

It may or may not be the computer but seems to me you should test, replace and check quite a few things before ordering that ecm. Check all ground cables making good contact, check and replace the throttle position sensor. Unplug the front O2 sensor and see if it stops the behaviour. Small things first and then get bigger. No reason for them to just throw a distributor at it and a cat. Find another shop ASAP!

To check if the cat was clogged they coulda just removed the front O2 sensor to let it breathe, no need to cut it off!

Also check all vacuum lines and change PCV valve with dealer part only.

If they removed the distributor they need to reset fuel sync to 0 degrees with an expensive scan tool!

How bout routing sparkplug wires per TSB and insulate them with split conduit to prevent spark jump

 

As said above, check all the vacuum lines, if the 02 sensor is original with more than 70,000 miles on it, its bad and needs to be replaced. Check the crank shaft position sensor, it can and will cause the problem your having if its going bad. Has the plenum gasket been replaced ?, if not, its also something that needs to be done.

 

Thank you so much Beeker and Ram Driver. I very much appreciate each of you taking time to reply. I will make sure that each of these things are checked one by one as necessary and will update when the problem is identified. I went ahead and ordered the computer last night as I didn't know what else to do. It does come with a 30 day money back guarantee if I need to return it.

The guys at the shop where it is are really nice guys...they have just been stumped on this problem. It occurred to me to check this forum, since I figured there would be someone here that may be familiar with this issue. It seems to me the most experienced Dodge mechanics are located right here on this forum.

I have not changed the plenum gasket yet, but plan on doing that in the near future. To be honest, this truck has been nothing but a huge money pit with something significant and expensive tearing up every other month it seems. I'm actually embarrassed by how much money I have in it, considering it books for less than $5000.

 

My truck was a basket case when I got it, because the previous owner did absolutely nothing to take care of it. It does take a lot of money to fix these trucks if you can`t do it your self (im not able to do it my self), but because these are good trucks, it will be worth it when its done.

 

If you have the time, there's no reason anyone shouldn't 've able to work on these trucks. Tools are a valuable investment and the knowledge to use them is even more valuable. there's never a bad time to start wrenching. Plenty of people on this forum started like that. And if you post pictures we can be nice most of the time

 

^Yes that LOL

Keep us updated on your repair. Good luck