98 Grand Am GT 2.4L - Low Oil Pressure
amcswebs
09-25-2005, 10:57 AM
I guess its time for this backyard mechanic to seek the advice of those that know more than myself (which is likely just about everyone).
We bought a 98 Grand Am, 2.4L, 5 speed standard not to long ago thinking the 'tick' we heard was a minor one and could be easily fixed. Unfortuantely, I had only worked on older engines and had NO idea what i was getting into. Now I need help.
This engine, it turns out was much louder than most so we took it to our favorite mechanic to see if he could help us figure out what was wrong. His answer (and he was sure) was that the timing chain system was worn and making the noise. So we gave him the car and let him rip it apart to fix. Seems it wasn't the timing chain at all. To add insult to injury the car was returned with the timing set up slightly off which added to the noise.
Anyhow.. it was my turn.. I took apart the timing componants and then continued on to the cams/lifters to see what i could find. Seems the bearings in the housing (and on the camshafts) were showing some signs of wear and scoring so I picked up a couple of used ones.. cleaned em up.. made sure they were usable and replaced the existing ones.. LONG job for sure. Guess what.. Still loud.
Anyhow.. to make a very long story short I did what both the mechanic AND I should have done in the first place.. I pulled out the oil pressure sender and connected a mechanical guage to see how the oil pressure looked. The oil it seems IS flowing, but not with enough pressure to make the mechanical guage register.
After HOURS of reading on the various forums I have reached the conclusion that it must be one of 3 thing and I need YOUR ideas or suggestions before I once again rip this motor apart. I just don't have the knowlege to make an informed decision on what to do, or what to look for on my own. I hope you can help.
Possible causes I have come up with.
1. Pressure relief valve stuck open (would this cause low pressure? Anyone know if its possible this is what it could be? How do I check?)
2. Oil pump is shot.. (I believe that it comes complete with a new pressure relief valve, but i HAVE to try and keep costs down now as all the trial and error checks, etc have become costly)
3. Engine Bearings are shot.. (This motor runs SMOOTH as glass.. would it do this if the engine bearings were shot?)
This car is SO damn clean throughout and is so much fun to run I just hate to think it is junk. We have had to buy another car for transportation and when I'm done this one will likely be sold at a loss, but I just can't stand being 'licked' on a problem and would hate to see a car that looks and runs like new get junked.. what a waste.
Can any of you experts help me?
We bought a 98 Grand Am, 2.4L, 5 speed standard not to long ago thinking the 'tick' we heard was a minor one and could be easily fixed. Unfortuantely, I had only worked on older engines and had NO idea what i was getting into. Now I need help.
This engine, it turns out was much louder than most so we took it to our favorite mechanic to see if he could help us figure out what was wrong. His answer (and he was sure) was that the timing chain system was worn and making the noise. So we gave him the car and let him rip it apart to fix. Seems it wasn't the timing chain at all. To add insult to injury the car was returned with the timing set up slightly off which added to the noise.
Anyhow.. it was my turn.. I took apart the timing componants and then continued on to the cams/lifters to see what i could find. Seems the bearings in the housing (and on the camshafts) were showing some signs of wear and scoring so I picked up a couple of used ones.. cleaned em up.. made sure they were usable and replaced the existing ones.. LONG job for sure. Guess what.. Still loud.
Anyhow.. to make a very long story short I did what both the mechanic AND I should have done in the first place.. I pulled out the oil pressure sender and connected a mechanical guage to see how the oil pressure looked. The oil it seems IS flowing, but not with enough pressure to make the mechanical guage register.
After HOURS of reading on the various forums I have reached the conclusion that it must be one of 3 thing and I need YOUR ideas or suggestions before I once again rip this motor apart. I just don't have the knowlege to make an informed decision on what to do, or what to look for on my own. I hope you can help.
Possible causes I have come up with.
1. Pressure relief valve stuck open (would this cause low pressure? Anyone know if its possible this is what it could be? How do I check?)
2. Oil pump is shot.. (I believe that it comes complete with a new pressure relief valve, but i HAVE to try and keep costs down now as all the trial and error checks, etc have become costly)
3. Engine Bearings are shot.. (This motor runs SMOOTH as glass.. would it do this if the engine bearings were shot?)
This car is SO damn clean throughout and is so much fun to run I just hate to think it is junk. We have had to buy another car for transportation and when I'm done this one will likely be sold at a loss, but I just can't stand being 'licked' on a problem and would hate to see a car that looks and runs like new get junked.. what a waste.
Can any of you experts help me?
kok328
09-25-2005, 11:42 AM
You couldn't pay me enough to install used bearings! :2cents:
skibum1111
09-25-2005, 01:43 PM
If there is no power loss then your bearings should be ok, when bearings fail they knock, the knock sensor indicates this and changes the timing, thus the power loss. Sounds to me like the oil pump is toast, these things do happen from time to time. If you are going to tear it down that far, look at the pressure relief valve when you have it apart, even if its stuck open change the pump anyway as you have it apart already as its nice to know what caused the problem. Also, when you have the oil pan down check the rod bearings, grab the end of the rod and see if it wiggles around on the crank or higher up, if thats the case put it back together and throw out the motor or rebuild it.
GTP Dad
09-25-2005, 03:01 PM
Like skibum111 said the oil pump is probably shot or as you said the pressure relief valve may be stuck open. However, the problem is that if you checked it with a manual pressure guage and getting no reading then you need to stop driving it and correct the problem. Unfortunately, even if you replace the bearings you are only buying a little time because if the car has no oil pressure everything is going to fail in the near future.
I do not, however, think that you should junk the car. If you have to rebuild it then you are looking at a pretty hefty chunk of money. You can purchase a guaranteed used engine or a reman engine for a lot less money. Since you are going to need to pull it anyway if the bearings are shot then if you go that route you can save a lot of time and money. The 2.4 is readily available and shouldn't be hard to find. If you need an engine check the local wrecking yard or car-part.com or cherry-auto.com. all can help you out. Good Luck!
I do not, however, think that you should junk the car. If you have to rebuild it then you are looking at a pretty hefty chunk of money. You can purchase a guaranteed used engine or a reman engine for a lot less money. Since you are going to need to pull it anyway if the bearings are shot then if you go that route you can save a lot of time and money. The 2.4 is readily available and shouldn't be hard to find. If you need an engine check the local wrecking yard or car-part.com or cherry-auto.com. all can help you out. Good Luck!
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