Hello. I'm new here so please take it easy on me! Just purchased my first Fiero, 85 GT. One owner car, well documented. I've always wanted one since I was a kid. I drove the car home after purchasing it. It was approximately a 125 mile drive. Upon arriving home I noticed that the rear of the car was greasy with oil. I looked under and noticed it was leaking oil or what appeared to be oil. It wasn't like gushing out but there were several decent sized puddles on my garage floor. I would say 4 to 5 puddles about the size of half dollars. I inspected the car well before I purchased it. I test drove it for 10 minutes or so and everything was fine. No leaks or anything. As I said the car was well maintained and the former owner insists the last time he drove it, there was nothing wrong. Good man and I believe him. It was not his everyday driver of course and it had actually sat for a long time since he had driven it. Here's my thinking.... The car has set and perhaps something happened on the ride home. It seems like it has to build pressure and warm up good before leaking. After it cools, no leaks. I crawled under and inspected the oil filter and the adjacent area. Everything seems to be fine. The surrounding areas just seem to be wet with oil. Nothing obvious that I could see. Its a stock 2.8. I've read through a lot of the existing threads on here, I think and I couldn't quite find the same issue so that's why I'm asking. I apologize if this is a repeat. If so please direct me in the right direction.
I would suspect the distributor O ring... check the area around the distributor base, and if it looks wet, you have a leak! It's super easy to replace, I just did mine a few days ago... It started leaking badly on the last oil change.
The front valve cover appears to be dry. Hard to really tell on the one closest to the firewall. I've inspected the distributor area and the best I can tell it looks rather dry in that area. From what I've read, the distributor O ring is a common leaking point so I'm gonna start there. I can turn a wrench but I'm by far a seasoned mechanic. My bro-in-law is legit and he's planning on educating me in mechanics this weekend. Hopefully its a simple fix. The car is amazing and I'm just a little bummed that its got a leak. I guess if that's the worst thing that happens, I'll be in good shape. If anything else comes to mind, please let me know. Engine had a full rebuild less than 10 years ago at around 60k miles. It's at 99k now. From the documentation I've been able to determine that just about everything that could have been replaced as far as gaskets and seals was. So I'm hopeful that it's nothing major. Would the car sitting for an extended period cause issues such as this? Thanks for the help!
Congratulations on getting your first Fiero! Sometimes when the cars sit for years with little driving the seals and gaskets can start to leak during regular driving. Case in point -- all three of the 5 spds I've gotten started to develop leaky Clutch Slave Cylinders (and sometimes the Master as well.) My last one was especially impressive: to get it transported the driver was able to start the car, move it around, and drive up onto a two-level car carrier. The next day when he drove it off at my house the transmission was already getting finicky. The next morning I couldn't work the clutch at all. This was a sobering experience for me: my original plan was to fly up to San Francisco to pick up the car then take a leisurely drive down to So Cal. The reality would have been a break-down on the highway and $$$$ to get it fixed. So be glad you made it home in one piece
Possible leak area in addition to those mentioned already: the Oil Pressure sender (picture below). Mine just sprung a leak and over a 2-day period sprayed an impressive amount of oil around and below it. I think this is an unusual failure mode, however. Good luck on finding your leak and Welcome to the Forum.
Ok so we inspected the distributor area. Doesn't appear to be any sign of leakage. Everything looks dry on top of the motor. The valve covers appear to be in good shape as well. A little wet but nothing like the amount of oil I think would be coming out of them to produce the amount of leakage. Turned to the oil sender unit and it appears to be clean and dry. Appears to have been replaced not long ago. The oil definitely seems to be coming from the filter area. The oil filter was pulled and replaced and still leaks. It will only leak when the engine is hot and the car is moving. I noticed a nice sheen of oil all over the rear bumper area today as well. Turned to the oil sender tube and its so hard to tell if its the culprit. It's definitely the original one to the car. Oil doesn't look to be coming from the transmission side. Everything looks pretty clean and dry over there. The starter does have oil all over it as well. We cleaned the entire area as to hopefully catch where its leaking from but no luck. It's like the oil just magically appears all over everything after a test drive. The engine oil level did drop some and the oil pressure gage in the car does bounce around quite sporadically. Drain plug looks good and from what we can tell the oil pan gasket seems to be ok. Hard to tell for sure though. I'm not the best mechanic by any means but I just don't see that amount of oil spraying from the oil pan gasket. The best I can tell is that when driving its spraying or leaking it out at a higher rate. When the car is stopped the residual oil leaks off and after a small but decent size puddle, that's it. No more leaks. I'm stumped to an extent. Any ideas?? I guess tying to replace the oil sending unit and oil sender tube will be my next step. I've tried to search for the stainless steal tube on the fiero store but cant locate it.
I thought about dye but I think the problem with that will be that its throwing oil all over everything under the car just about. It only leaks when the car is moving so when I stop and look under I can see it leaking still but oil is all over everything and eventually it stops leaking. I think whats leaking down after I stop driving is just whats been spewed out and its just leaking off. I would say with dye everything is just going to light up under there........
Are you sure it is engine oil and not transmission or CV joint lube? CV joint stuff will be thick, but transmission fluid it fairly close to engine oil in viscosity. I have a drive shaft seal that leaks, I haven't gotten around to fixing it yet, it only leaks when the can is warm and being driven.... And flings it all over under there, so much so that if it sits for a while it will get a few different (more quarter size) puddles from the fluid dripping off different parts. May be orth looking at. Check the transmission fluid level. If it is a manual you'll need to remove the speedo sensor to do this.
Towards the back of the car (on going into the transmission). It's located near the coil but much closer to the ground. It a cylindrical thing with a bolt tightened down on a little tab that holds it in. When you pull it out, pull it out straight so you don't drop the speedo gear into the transmission. There should be a slight mark on the shaft of the speedo sensor that tells you it is full. I usually just fill it approximately to a centimeter above where the speedo gear sits. (This should all make sense as you take it out and can see how it works.) only "tough" part about it is the potential to drop the gear into the transmission, but it can't go far. You'll need a retracting type grabber to get it out though since the gear is plastic. If you pull the sensor straight out this shouldn't happen. Also, make sure it is seated well when you put it back it and don't let any dirt fall in there, in fact I'd wipe the area around it before you remove the sensor. If you need fluid be sure to use synchro-mesh transmission fluid.
Ok I ended up getting the dye and adding it to the oil. As I suspected it was hard to really tell exactly where the leak was coming from. I did look to be more concentrated around where the oil pan bolts behind the starter. So I opted to change the oil pan gasket. When I pulled the starter and shield behind it, there were no signs of leakage in that area that I could tell. Everything appeared to be good and dry. The area between the starter and the oil pan appeared to be where the heaviest concentration of oil was coming from. Ok so I changed the oil pan gasket. The gasket was old and very brittle. Also the oil pan bolts were not tight at all. I thought for sure that would take care of it. Buttoned everything back up and let it set overnight. Added oil and a new filter and took the car out last night for the test drive. I let it run for about 20 minutes and it didn't leak a drop. I made about a 4 mile drive and when I got back to the garage she was leaking. The oil looked to be coming from the same area as before, at least the drips on the ground were in the same spot as before. I did notice that it didn't appear to be as much oil as before the gasket change so I don't feel to bad that my brother and I spent several hours changing that gasket. No doubt it was leaking as well. I checked the distributor again and from what I could see looking down at the base, there's no signs of leaking there. Could the distributor O ring be leaking and I not be able to see it from looking down at the base of it? What about the dip stick tube? Is it possible that it could be the leaking point? We checked it and everything appeared to be ok along with the oil sending tube but as stated before the dye was all over everything. Very hard to trace it back to the exact point. It doesn't appear to be coming from above though like from the valve cover or the distributor O ring. It only leaks when the car is moving. Sitting still at idle and it will be dry. It's like it has to have oil pressure built up before the leak shows up. Does anyone have anymore ideas as to where the leak could be coming from and perhaps a better way to diagnose it?
The base of the oil pressure sender would be suspect. The pre-88 ones seem to have leaking issues. I know this was brought up before, but you may not be able to see anything wrong when oil pressure is low. Maybe you should race the engine for a few minutes with a piece of cardboard next to the sender and see what happens.
[This message has been edited by Gall757 (edited 05-04-2015).]
Its been changed to the 88 sending unit and it looks to be dry as a bone. Oil pressure gauge seems to be functioning properly. There's no trail back to that area that I can tell. The man I bought the car from had mentioned before that he had an issue with the oil filter not seating properly and he had a leaking issue. I mean I purposely bought a K&N filter because it wrenches on so I could get a better bite on it when installing it. To me it just doesn't seem likely but has anyone ever heard such a thing before and is it possible? This is the third different filter I've tried so I'm thinking this is not the culprit. As I said before the amount of oil that leaks does appear to be smaller amounts so that leads me to believe the oil pan gasket was leaking but I'm lost as to where it could be coming from.
My guess is that at some point the rubber seal from the oil filter remained on the motor as opposed to coming off with the old oil filter during an oil change. If this is what happened you now have two rubber seals in between the motor and the filter causing the leak. Just my guess but you've mentioned the oil filter a couple times now as a possible culprit. Spin it off and make sure there isn't an extra rubber seal "glued" to the motor where the filter goes. Worth a shot.
Cut up a cardboard box and get a bunch of flat sheets to put under, around and here and there in the engine compartment. Put one near the bottom of the distributor.....valve covers...etc. Start the car and run it up to about 4000 rpm for 30 seconds. If nothing is found, the problem may be with the transmission and not the engine. Suspect the output seals on the axles.
Ok folks, oil leak solved! I wanted to definitely post a reply with the solution. Moved on to the oil dipstick tube after the oil pan gasket. It was found that the O Ring at the base of the dipstick tube had worn out. Replaced the O Ring and buttoned everything back up and no leaks whatsoever. Hard for me to imagine it putting out that much oil but it obviously was. My guess is that the car had set for a long time before I purchased it and the O Ring failed sometime during the ride home, approximately 130 miles. Everything seems good now. As stated before I'm new to this forum and I just wanted to take a second to Thank all of you who posted and tried to help me. I love Fiero's and have always wanted one but I sure don't know everything about them. I've heard and I'm learning first hand that PFF is a great place with great people who actually care and will help you out. My first post / experience has been great! I've got a lot of things I want to change and upgrade on my car so I will have many more questions. I'll be back! Thanks again.