I have a 98 neon with a 5spd trans and 2.0 motor. Recently my trans has been making a noise in 4th and 5th gears above 2000 rpms does anyone have an idea of what may be the problem and an easy fix for it if so let me know

 

Not really enough information to diagnose anything as it could be just about anything.

Start by checking the manual transmission gear oil fluid level - low levels can cause gear grindage and other issues.

 

i did have my fluid level checked out by a transmission shop and they said the fluid look normal and was full they are the ones that said i shouldnt drive it so i dont but they wouldnt tell me what could cause the noise i also heard that it could be the syncronizers but i have no clue im new to having a neon so im not sure much about the transmissions on them

 

When the synchronizer in my Nissan Sentra started going out, at first it would not stay in 5th gear (it would just pop out) usually when I accelerated or let off the gas. Then later, it would not even stay in 5th at all - even if I tried to hold it there. But at no time did it make any noise. Were you having problems keeping it in gear?

The cost of rebuilding a tranny for an older car is really not worth it, especially if you have any junkyards around you that will sell you an entire low mileage 5spd tranny for about $250 or less depending on where you live.

 

im having a trans shop get a rebuilt trans and put it in another question maybe you could answer what is a good way to get rid of **** poor idle that it has it does not have a cat on it but does have a muffler

 

As for not having a cat, you must be getting an error code from the downstream O2 sensor as the cat "filters by burning off" the unburned gas and other noxious fumes (Nitrous, etc) so that isn't helping things. However, that will not affect your idle issue. T

That error will not light up the Check Engine Light (CEL), but will be stored in the PCM for readout on an ODB-II reader (go to Autozone, Advance, NAPA for a free readout). Make sure you write down all the codes given.

I had the same problem so here is a brief summary of what I did and I hope this helps:

1) check all your vacuum lines - especially the ones coming out of the evap canister - I had a rub hole in mine on the line coming out of the evap back to the gas tank - it goes over and around the passenger side tire well. The clip rubbed a hole in the line - about $1.00 to fix.

2) If it has been awhile, replace the Air filter. Sounds like a silly thing to say, but if you haven't replaced it in awhile, it could be clogged up and not helping things.

3) Take off and clean the hell out of the throttle body. Pay special attention to the throttle butterfly and IAC area. In fact take the Throttle position sensor and IAC sensor off and clean the heck out the holes where they go very well. Use a good carb cleaner for this task.

4) Clean the MAF/MAP sensor. It is attached to the intake manifold and measures the airflow into the intake and helps PCM regulate the gas input. It needs cleaning every so often to keep it tiptop. ONLY USE an approved MAF sensor cleaner on this item! Anything else can damage it!

5) If you have anything other then cheap *** (Champion, AC, NGK) copper resistor plugs, ditch them. I don't know if the newest indium plugs are OK, but platinum and split fire plugs suck in a Neon.

6) Check your coil and wires for proper resistance levels. If out of spec, replace the bad ones. If your coil is out of spec, let me know as I can sell you one super cheap. I thought mine was bad, but it was not.

7) If you can, have someone check the fuel pressure at the rail using the port on the rail. You need a fuel pressure guage and can probably get a loaner at Advance, Autozone, NAPA, O'Reilly, etc.

8) If your car is a 1995, replace the fuel filter as it is external to the pump and easy to do and if your car has over 60000 miles on it without changing the filter, it needs one anyway. If it is not a 1995 model, I would not do anything until I have tried #7 above as it is a major PITA and big mess to take the fuel pump assembly out of the tank and replace things (and expensive too unless you can get the individual parts instead of having to buy the whole darn thing).

9) Sometimes, even though the error code may not be thrown, the upstream O2 sensor just needs to be replaced. This O2 sensor is the workhorse of the two. If you haven't replaced the sensor and have over 70000 miles on the car, just do it anyway. It won't hurt and may help and they are not that expensive. A slightly malfunctioning upstream O2 sensor can affect your idle.

Most likely one of these is affecting your idle. I ended up having to replace my throttle position sensor, upstream O2 sensor, and my IAC (my car had 175K miles on it and I don't know when/if it had ever been done), and I did have error codes in my PCM to indicate that they were not fully functioning.