99 neon 2.0 dohc. So I got oil on top of the manual transmission leaking down, and I think it might be head gasket or oil pressure sending unit. not sure where the sending unit is, and i have been baby-ing the car so I really dont think I blew the head gasket. any ideas or should I just start to dive in for the head gasket??? also I believe with the amount of oil leaking, and on top of the tranny, that it is probably a pressurized oil leak, not just a gradual leak. happend on my way home from work and its all highway, 60 mph 5th gear. any ideas fellas????

 

Oil pressure sending unit is on the back side of the motor (firewall side), on the rear of the engine (close to cylinder #4). About 3 inches above the oil pan gasket. If you remove the airbox, you can get to it easily from up top, or you can get under the car and reach around the rack and pinion unit to get to it that way, but you really cannot see it either way as there is just too much stuff in the way to really get eyes on it. Now if you have access to a lighted snake camera, you are golden.

How fast is fast? 1 quart a day? 1 quart between oil changes? Somewhere in between? Is it truly leaking the oil, or burning it?

Do a compression and a leak down test first. Popping the head for no known diagnosed mechanical issue is not wise. If you do that, then depending on the mileage, you should also have the head redone (to regrind and reseat the valves and replace the valve seals), and put on a new timing belt, water pump, etc.

Why? Because if you spend the money tearing off the head, you might as well make sure you won't have to do it again anytime soon.

 

good call on the tearing the head off, at 113k I might as well do the job right. and fast would mean about half a quart in one 20 minute drive. left a puddle about 6 inches diameter when I stop at a store for a few minutes (5 minutes at most), then I got home and popped the hood and saw oil steams on top of the transmission leading down. I almost wonder if the head bolts loosened up, but I dont have the time or much cash to do the whole head gasket process. Checked the coolant this morning and looks good, no oil... yet. checked the oil dip stip, looks clean, no coolant. Its got a cold air intake so the stock air box is gone already so I will try to check the sending unit. once I check that I think I will try to start it and verify how bad the leak is and where from, then Im sure I will be back on with more info... crossing my fingers its a easy fix....

 

keep in mind it is 8 degrees today with 6 inches of snow on the ground... not ideal to work on a car, but I did get out there and clean up the residual oil I saw last night and then started the car and watched all over and there was no new oil that I could see. so I laid on the ground and watched to see if any oil was dripping down, but there again no signs. The one thing I did see was oil all over the driver side of the rack and pinion and some of the firewall, almost like "sprayed" on it but i was on the highway 60 mph. so I pulled the clutch cable cover on the transmission and notice engine oil all over the inside of the cover.... would the rear main leak into the transmission case and the flywheel throw the oil out of that clutch cable cover? not sure it would do that at all, doesnt make sense at least, and not sure I have ever heard of anything like that. I have to work tonite, but I will most likely try to get the car up in the air and try to start it and fid a source of the leak... was also thinking about pulling the transmission inspection cover to see if any oil comes out... does any one know if the internal core of the transmission take a gear oil or something??? I might be facing a transmission leak rather than oil... I know mtx dont take fluid but wouldnt it be a sealed system with some kind of fluid like a differential or transfer case???

 

ok well I figured it out.... but it is not good. got some gear oil and started filling the mtx and once I put almost a whole quart into it, it started leaking out of the bell housing.... ooohhh hell. so does anyone know much about the mtx to give me an idea on the seal or what may have happend to cause this? I obviously need a good deal on a mtx if anyone knows where to get a good one.... this sucks

 

Two problems. One, the seal on the "front" (bellhouse) side of the tranny is THE biggest pita to replace as it requires you to remove the tranny to really get to it. The other is that if you have that much tranny oil already leaked out, you may have gear damage too. Maybe not, but you still have to get that sucker out just to really do what you need to do.

Another problem is that now your clutch is coated with glop. That has to be replaced too. While you are at it, you probably need to change out the seals on the transfer case to keep from losing it there too.

Really, your best bet is to find a replacement tranny from a Junkyard, pop in new seals, put on a new clutch, fill er up and drive that mother. A JY tranny from a car with a decent number of miles shouldn't run more the $300-$400. You'd spend that alone trying to diagnose what may be wrong with yours, even if you find someone who still works on manual trannies in your area.

 

Pretty sure I will go that route, just dont have the cash at this moment and I need the car, but I will just have to deal. Das has a trans from his 96 with 183k for $250 that would get me mobile at least then I can go from there, but yea theres most likely gear damage and if I drive it Im lookin to be left on the side the road. but at least I know what the problem is and I can go forward from here... thanks for your help bro!! I appriciate it.

 

Don't be afraid of that tranny with 183K on it. If Das had it, it was probably taken care of. My 1995 neon is just now crossing the 190K mark and my tranny still shifts like a dream. I have no idea how it was treated before I got the car because my friend who had it before me did nothing to it but drive it until it blew the timing belt....he paid $200 for the car BTW.

I put new oil in at 157K (along with new seals and a new clutch) because I was rebuilding the engine and I have not had any issues with the tranny.

I am going to drive the wheels off this sucker, run it till the motor seizes or gives up, or fall on the ground when/if the car under my seat rusts out (no rust anywhere...yet....).

 

So, I got a transmission from a salvage yard and put it in, wasnt as hard as I thought it would be, but I found out why the "old" mtx was leaking. A bolt had backed out of my clutch cover plate and punched a hole in the case by the axels and then punch a hole in the bell housing the size of a quarter. no wonder I got such a good looking car for so cheap. guy who sold it to me just didnt want to do the work to replace the mtx. Got the "new" mtx in and the car runs GREAT. feels solid and drives good, but I think I need to replace my tie rod ends and maybe the ball joints, might as well replace the struts then get an alignment and this car will be golden. Thanks for all your imput and help!!

 

Just as a further FYI to the masses, parts and all, what did you sink into the project?

Glad you are back in business. I just love my Neon. I finally replaced my bad windshield yesterday with a brand new one, and it only cost me $166.02 total at Safelite! They did the work and I just watched. I suppose I could have tried to do it myself, but even a used glass was going to cost me $75 - and that does not count for a new seal, etc. I would have had to get too.