2 probs rough idle, ac problem

[dcathey]

Hey guys I have developed some new probs.
1.) I was leaving a jobsite today and on my way to get some fuel. All of a sudden the Service Engine Soon Light pops up and it idles very rough and I have to struggle to get up to a decent speed. It will eventually get there on a highway but leaving red lights is miserable. I have no idea what this could be. This is the most important problem and I am going to Autozone to see if they can run a code check for the service engine light. any input would be greatly appreciated.
2.) My a/c has something seriously wrong with it. I want to have the problem addressed but the past 2 times I have taken it they cannot fix it(last summer). When I accelarate it usually blows cold and normal. When I am at a stop light it blows hot or also when im up to speed. I have had a vacuum pump replaced before and that helped for a while but it ended up messing up again. Oh and also it really acts up more the warmer the weather is.My 4x4 is also spotty as well. Only works when it feels like it. What should I be looking for to address these problems?

 

[JLDickmon]

Hey guys I have developed some new probs.
1.) I was leaving a jobsite today and on my way to get some fuel. All of a sudden the Service Engine Soon Light pops up and it idles very rough and I have to struggle to get up to a decent speed. It will eventually get there on a highway but leaving red lights is miserable. I have no idea what this could be. This is the most important problem and I am going to Autozone to see if they can run a code check for the service engine light. any input would be greatly appreciated.
2.) My a/c has something seriously wrong with it. I want to have the problem addressed but the past 2 times I have taken it they cannot fix it(last summer). When I accelarate it usually blows cold and normal. When I am at a stop light it blows hot or also when im up to speed. I have had a vacuum pump replaced before and that helped for a while but it ended up messing up again. Oh and also it really acts up more the warmer the weather is.My 4x4 is also spotty as well. Only works when it feels like it. What should I be looking for to address these problems?

I'm betting that your rough run/SES light is a burnt under valve cover harness (UVC) the valve cover gasket serves as a bulkhead for the injector & glow plug harnesses, and failures are quite common on the 7.3

when you took it in last year for the A/C, what did they do to it?
I'm going to start there.

 

[dcathey]

a litle update. Went up to autozone to see if a computer code would come up and it diadnt. Truck is smoking badly and is very slow to accelerate. Takes a while to even get up to 50. It also shifts very hard at about 2500-2600 rpms. If you guys can my number is 9122422209 and would appreciate any input if you could. also added 10 oz of Lucas fuel system cleaner to 15 gal of diesel. What should I try next?

On the ac I had a service comp. tell me that it was the vacuum pump and they replaced. My dad had it last summer and did a couple things but never got it working quite right. I was told that it may be a simple vacuum line but since I am going to take it somewhere to get it done right I want to have the problem as pinpointed as possible to save on fixing the wrong things...again. But that is for another day. I gotta get this new problem with the terrible idle and acceleration. How hard is the UVC problem to address? Can it be a DIY job?

 

[BJS]

UVC is a relatively easy job just time consuming.

You need to remove your intercooler tubes, remove the valve covers and then replace the harness and possibly valve cover gaskets depending on what is damaged. (expect a 4 hr job the first time) I'd recommend replacing the glow plugs while in there as they are usually the culprit for a filed UVC.

The A/C problem honestly sounds like a bit of an overcharge or a dirty condenser (possibly evaporator). Overcharge will put too much liquid refrigerant in the condenser so that there is not much room for the condensation to take place, with the high volume of airflow at speed it works fine but when you stop then it does not have the airflow to adequately condense the refrigerant.

 

[dcathey]

Any other ideas on what this could be and is there a UVC on each side or just one. Any ways to test if there are more than one. I am ordering parts tommorrow and dont need any hangups. Thanks and also any tricks to this project that I should know about?

 

[dcathey]

Hey guys....rode up to sav. to get parts from int. and saved 200 bucks by the way. and got to swing by bass pro but anyways. got home and cranked up the truck to put in garage to start working on it and drove around block...guess what. No problems whatsoever. I decided not to mess with it tonight since i wouldnt know if i even fixed the prob. I then drove to the shop to do some stuff and sure enough no pros whatsoever. Do you guys still feel as though it is a uvc harness?

 

[Nautorious1]

Rough Idle and A/C issue

Just to go back to basics, how long has it been since you changed your air filter and fuel filters? Diesels are very sensetive when it comes to the fuel system. I'm sure you checked those issues first, but I just wanted to make sure because sometimes we all look for the worst thing first and forget about the easy stuff to eliminate. Also sounds like it could have simply been bad fuel or water in the fuel, maybe from where you last filled up. Diesel fuel can also develop algae over time, which can clog filters and injectors. Get some diesel fuel algae treatment and run it in a few tank fulls down to empty and then replace your fuel filter again. See if that helps.

 

[dcathey]

Finally going to replace uvc. Truck worked fine on friday and then started messing up agian friday evening. I did not mess with it much this weekend. Cranked it up yesterday and it took 3 times to get it going jus to move it into garage. Anything else that may be the culprit. IT has absolutely no power when it starts acting up. ALso shifts very hard at higher rpms.

 

[JLDickmon]

that's the problem with being an internet mechanic, you're always guessing...

yes, I still would pull the UVC's and check them, heat may have splayed a connector somewhere and it's possible it's not always getting good contact.

 

[dcathey]

Changed driver side to no avail. I had the codes ran and I got p1247 and p1316. Does this offer any more insight to my problem? I think I am going to do the passenger side tonight.