2000 C5, perfect condition. I'm sitting in a drive-thru tonight a few minutes after starting my car, and I noticed that my oil pressure was completely pegged on my dash oil pressure guage, which has a max of 80, and on my HUD as well. Chcecked my DIC and it reported my oil pressure as 130, with no fluctuation whatsoever. My car was just idling at several hundred RPMs, so obviously none of that could be right, and I've never had any oil pressure problems before.

As soon as I left the drive-thru I turned my car off, and I noticed that as soon as I turned the key to ON, before I even started the car, the oil pressure gauge was pegged. So, it just confirmed what I already knew, that it was definitely nothing engine related.

My question is, what's the most likely part that will need to be fixed, and does anybody have an estimation of parts and labor? (I won't be doing it myself)

TIA!

P.S. I was surprised to see that my DIC wasn't throwing me any warnings about high oil pressure... Either it knew that it was just a gauge or sending unit issue, or I guess extremely high oil pressure isn't one of the things it warns you about.

 

Sending unit is done. Very simple fix.

 

Great, that's what I figured, though I had no clue how difficult it would be to replace. If anybody else has any input please feel free to chime in.

 

No more input is needed my friend.

He's definitely correct, this is a very common issue. There is a sticky about it I believe at the top of this section.


http://forums.corvetteforum.com/c5-t...iy-thread.html

there's the link, post # 60. READ THE STICKIES!!

 

Yes, read the stickies as their are probably thousands of posts regarding this issue through lots and lots of threads. When GM replaced the original design sensors, many of us, including me, got a new one, installed it and the new one lasted anywhere from a few minutes to a few weeks, then it too died. Now one person will differ with me on this and that's Ok as we're all entitled to our opinions and you should decide for yourself. The original sender was made of brass and the replacements are aluminum. Some of us, relocated and the problem went away. I'm not hearing of anyone getting new brass ones now that are failing and installed in the original location. It takes about 30 minutes to remove the intake manifold, replace the sender and reinstall the intake manifold. Not that hard of a job. Make sure you have the torques available and a couple pieces of tape for the rear bolts on the manifold as you'll need them.

 

Here's a link to the best DIY on the forum IMHO

http://forums.corvetteforum.com/c5-t...y-vectorz.html

 

Well thanks for everyone's input, greatly appreciate it. As far as stickies go, believe me, I've read more than my fair share, and I'm familiar with the vast majority of common C5 problems, having owned mine since I bought it new in 2000. If this is such a prolific problem, say for example like the gas gauge reporting empty problem, then I can't imagine how I've never once heard about it, but the fact remains that I haven't.

Anyway, I'll check out the provided links, thanks again

 

Thanks for the input about brass and aluminum senders. I'm a little confused though because you said the aluminum senders replaced the brass ones, but you said you hadn't heard of anybody getting new brass ones now that are failing. Is there an option to buy the brass OR the aluminum senders?

Looks like it's a doable job for a handy do-it-yourselfer, but I'm definitely going to have RPM Motors do it for me. I'm disabled compliments of a near fatal skydiving accident and don't have a lot of mobility, so I'll put it in their trusty hands. I want to make sure I get the best sending unit available though. Mine lasted more than 10 years without the slightest problem, and I'd like the next one to last equally long if possible.

 

When my sender goes out, I plan to get the relocation kit.

At that time, I also plan to replace the air valves. (I can't remember their exact name, but I've gotten the trouble code for them a few times.) They are basically check valves where the diaphragm deteriorates and sticks.
You see one in step 8 of the link given above. It's just to the right of the guy's thumb.
You see a portion of the second one in step 13. Up and to the right of the green circled oil pressure sending unit. The one in step 13 is the reason I'd change them while the intake is off.

 

For a while, all we could get was aluminum senders. Supposedy we are now able to get brass ones again and people are getting them. I'm not hearing of any problems being reported with the new replacements lately. Maybe GM woke up and saw there was a problem with their replacements whereas the original senders worked for many years. Anyway, the reports of failures now are related to old, original senders like yours and not the replacements too.

Now to clarify one item, I'm currently using an alunminum one myself but I relocated it to get it off the block and out of the intense heat back there. Its working fine but if I had to do it over again now, I would now attempt real hard to get a brass one. Also, I refused to cut the shroud open like so many did to make it easier to get to due to the quick failures of the new ones. No holes in mine now or ever.

 

Glad to see some fellow memebers helped you out with your situation. Been there brother. Its just one of those things. Here in case your having trouble finding a brass unit....

http://www.oreillyauto.com/site/c/de...3438&ppt=C0039

 

You may need to take off more than the intake to get the passenger side AIR check valve replaced. The head may have to come off?

I don't think the intake adds much space but I could be wrong....edit: after looking at picture (step) #13 I think so even more that you'd have to pull the head or the valve cover at least

 

This thread has a lot of good info on the AIR check valves.
http://forums.corvetteforum.com/c5-t...eck-valve.html
In the pictures, you can see the passenger valve is bolted to the back of the head. I think I can change it without removing the head. I'd have to unbolt it anyway if I was removing the head.
Post #79 has some good pictures of a disassemble valve that was bad. The rubber diaphragm is hardened.
Seeing them is the reason I will change it out in lieu of cleaning.

 

It's not the bracket that holds it to the head if memory serves...it's the big ole nut that you have to bust loose to get it separated from the AIR line.

 

Ahhhhh.
I guess it would be something I'd look at if the time came.

 

Thanks everyone for all the really useful information. So far after 10 years I haven't gotten any trouble codes related to the Air Check Valves (knock on wood), so if it would require taking off the head, or any significant effort beyond what has to be done to replace the oil pressure sending unit, I think I'll pass on that. Very good information though, it's always helpful to replace problematic parts or parts that are likely to break soon from routine wear when you're going to be putting forth (or paying for) the labor to access that part anyway. Ironically I just had to replace a bad knock sensor for the first time a month or two ago, and that would have been the perfect time to replace the sending unit had I known it was likely to fail soon. Kinda surprised nobody at RPM mentioned it if they're so prone to failure.

I ordered a replacement sending unit from Gene at GMPartsHouse night before last before I had any feedback on the aluminum vs. brass, and his site didn't have any details about it, so it looks like I'll find out when it comes in what I've got. Hope my replacement works as well as my first one did, I won't complain too loudly about most minor mechanical or electronic parts that fail after 10 years and 100K miles (not that they shouldn't last longer). Overall I'd say I've been reasonably lucky, although I've had my share of repairs. Most were in the first couple years, and those were almost entirely things that everybody has had trouble with (steering lock, rear differential, etc.).

BTW, does anybody know where to get the relocation kits for the sending unit, and does relocating it involve cutting holes in the shroud, or was that a procedure someone came up with unrelated to relocating it?

Thanks again!

 

what I followed

 

I just did this job last week on my 99 C5.

Buy the correct sensor, make sure it has the crush washer.

Enough of that, lets talk about what it takes to actually change it.

1) You will have to remove the intake runner from MAF to TPS.

2) It was a PITA to remove the tube from the MAF and I had to pull the air cleaner. IT also was a PITA to reinstall. Next time I will go with K&N dual kit

3) Manifold removal is relatively easy but disconnect the brake vac line and give slack so you can remove the clamp on the vac. port on the rear of the plenum

4) be sure to unplug the electrics to include the knock sensor and MAP sensor.

5) Once the plenum is out you will be able to get to the sensor and it is pretty easy straight forward change out.

6) No way no how could I reinstall the plenum AND connect the small hard tubing to the a/c vacuum controls. Finally I came up with a solid engineering solution to make this easy and the manifold installation becomes a 15 minute job.

7) I bought Emission tubing to exactly match the tubing on the a/c system. Then I used a vac hose rubber connection. Note the emission tubing will correctly plug into the vac. port on the plenum

8) Cut the emission tube about 12" long but allow it to naturally curve. Then connect with vac hose connector to the a/c connector. This will give you the room to connect to the rear of the plenum.

9) Moving the plenum back into positon allow the emission tubing to coil naturally and not kink while seating the plenum. (note be sure to connect vac brake, elects etch.

10) The plenum rear two bolts will not be able to install after the plenum is seated you will have to use tape to hold them up to clear and remove the tape after plenum is installed.

11) I put a TINY amount of blue locktite AFTER calling the company to confirm this was compatable with the GM recommended sealer / locking material

12) Learn a new language when installing the aircleaner. I did.