I did a search and looked through the FAQ. I have a 95 neon and when it gets warm (outside temperature as well as engine) i get a high pitch whine coming out of the computer box on the driver's side fender (pcm?) ALL sensors are new within the last year. Also my fuel pump is going bad. I can get a 95 neon with a good working motor for 200.00. The only problem is it's an standard and mine is an auto. I know there are differences between the two computers, but will the auto run on a manual computer? I'm getting so sick of putting money and time into repairs on this turd i's like to make it runnable for a little while longer. When the car does run properly it runs well but those occasions are rare. Can anybody PLEASE give me some insight on what to do?

 

I don't understand how the computer could whine! And yes there is a big diff. in computers between the ATX and the MTX. If you can get another car for 200.00 get it and park your turd. LOL Any how if you could swap the tranny into yours and the copmuter then yould add about 20 more hp to your car.Provided you changed fuel pump. Since you have an auto tranny there is bad news from mopar, they dont make a performance pcm for an auto, it is several hundred dollars cheaper than a replacement pcm thru dodge. If you had a mannual tranny. AFX makes one for an auto but it's about 3-400 bucks.STILL CHEAPER THAN A DODGE REPLACEMENT PCM. Its prob about 600 or so.The pcm in my 98 ACR would be about 900 atleast thats what the local garage told me upon ordering the mopar performance pcm for 268 bucks. GOOD LUCK.

Try NOENS.org,how to's

 

It really does. Maybe not quite a whine but like a squeal. You know the sound an old TV makes if you put your ear around the back? That's the sound....

 

There is nothing in the PCM to make any whinning noises. Check where it is really coming from.

 

I've even used a stethoscope. The noise IS coming from the aluminum box on the driver's side inner fender with all the wires coming out of it. I'll assume it's the computer.

EDIT: ok maybe squeal would be a fitting word for the noise.

 

It is not suposed to do that, I would assume it broken.

 

It is supposed to do that. The PCM may emit a high-pitched "whistle" sound after the engine is shut off. The sound may last up to eight minutes. The noise can vary in pitch and intensity from one PCM to the next and with changes in temperature and battery system voltage. This noise is due to the PCM being powered up after ignition-off to enable a diagnostic routine for the O2 heater operation. This diagnostic routine will only occur when certain parameters are met, which include engine operating temperature and how long the vehicle has been driven. This noise may also be heard with the ignition on and engine running, but is usually muffled by the normal engine operation sounds. Replacing the PCM may seem to eliminate the noise for a period of time, but this is only due to the system not meeting the qualifying parameters to run the ignition-off diagnostic routine. THIS IS AN OPERATIONAL CHARACTERISTIC OF THE PCM AND NO REPAIRS SHOULD BE ATTEMPTED.