Stealth R/T Posted October 5, 2015 Report Share Posted October 5, 2015 My oil pressure is great when I start the car, but as soon as it warms up the oil pressure drops to the L on the gauge. The car does not run hot, and when driving it does not make odd noise. The oil "squirt era are doing their job and I regularly change the oil,just curious as to why it goes from something to nothing. Thanks, zach Quote Link to comment Share on other sites More sharing options...
nightwalkerancestery Posted October 5, 2015 Report Share Posted October 5, 2015 For one, your gauge might be reading low to begin with. Wouldn't hurt to grab a new sending unit to rule that out. Gives peace of mind too. My restore hit a speedbump when priming by not getting oil pressure, so I thought. After a bit, it read pressure but was super low. Grabbed a new sending unit I had (have three) and suddenly showed 3/4-7/8 pressure at idle. The sending units are notorious for being bad/inaccurate with age. Next, as oil warms up it thins and the oil flows out from between the bearing surface and mechanical part quicker than when cold. If after replacing sending unit it still reads low, you may start experimenting with thicker oils. I run 15w to 20w oil in older Starion engines that show slightly low oil pressure. Things get worn and tolerances open up. Running 10w-30? Try 10w-40. Might help you grab a few pounds. Worst case, the oil pump is on its way. However, I've never had a SQ oil pump go bad even on my 270k mile starion with stock guides and all. Good luck! - Charles Quote Link to comment Share on other sites More sharing options...
importwarrior Posted October 5, 2015 Report Share Posted October 5, 2015 get an analog gauge and test it from the block.in pic below.this hose is priming the engine and it is a good location to hook a analog or electric oil pressure gauge.test your pressure there. ALSO it is a 1/8 BSPT or BSPP thread NOT NPT.try this couplerhttp://www.ebay.com/itm/Forged-Adapter-Fitting-Steel-Male-Connector-4AN-1-8-BSPT-C1-6-/381398520443 http://www.enginemachineservice.com/prime1.jpg Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 6, 2015 Author Report Share Posted October 6, 2015 Alright, i will have to do that and check the oil pressure. I'm in the process of whether or not i want to have a friend of mine start rebuilding the car from the block up. Id like to have forged rods,pistons, and crank put in along with a jet-valved deleted head. i also would like to have all the seals replaced,, the oil pump and main bearings, new timing chain and have the balance shafts eliminated along with new valves and cam (if possible) my budget would be anywhere from 2-5k for the motor and turbo, and if possible have the rear cv joints replaced and maybe even a new tranny, clucth and such. I know id never get my money back out of it, but id have a really uncommon bad car that is reliable and fast to, although i dont do drag racing, just so when a rustang or slomaro pull next to me and laugh at my 4 banger, i can leave them in the dust. any input on what i should start with and what parts i should use would be greatly appreciated Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 6, 2015 Author Report Share Posted October 6, 2015 Ive also noticed that when it runs with no oil pressure i dont notice any scraping, knocking or ticking along with the motor not overheating so i feel like the gauge is innacurate or like said before the sending unit is bad. the main bearings were replaced in 2001 so i feel like they shouldnt be it unless the crank is already worn Quote Link to comment Share on other sites More sharing options...
Funky Phil Posted October 6, 2015 Report Share Posted October 6, 2015 You dont need rods or a crank unless they are damaged. They are stout from the factory. 600hp+ stout Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 6, 2015 Author Report Share Posted October 6, 2015 No s***!!?? That's cool, thought the Pistons weren't the greatest though Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 7, 2015 Author Report Share Posted October 7, 2015 Here's a little tip I've learned from expierance and from other reliable sources. DO NOT RUN 15w-40 diesel oil in an old, dirty motor!!! The high detergents drag all the carbon, dirt and sludge out, and these contaminants will get into all of the little nooks and crannies of your engine before your oil filter can pick them up, scoring everything and burning your motor up. A good friend of mine whose has raced for many years informed me of this, likewise the best oil to run in these cars is one with a high zinc content and one that doesn't break down as fast so a good choice is castrol gtx 10w-40 SYN BLEND or valvoline 10w-40 high mileage. In the summer a good choice is castrol gtx 20w-50. Hope this helps Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 7, 2015 Author Report Share Posted October 7, 2015 The reason I said this is because I saw a post before with somebody saying it is ok to run 15-40 oil in these cars, while that might be true if the motors are clean or recently rebuilt, it is not true of a car with a dirty motor. Don't break apart the stuff that might be holding the insides together is a good way to look at it. Quote Link to comment Share on other sites More sharing options...
Dad Posted October 8, 2015 Report Share Posted October 8, 2015 And don't run it with no oil pressure, noise or no noise. Fix that! Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 8, 2015 Author Report Share Posted October 8, 2015 Haha, yea it's on the list. I'm going to do that thing suggested above and test the pressure from the block and see if it is just a bad oil sender Quote Link to comment Share on other sites More sharing options...
nightwalkerancestery Posted October 10, 2015 Report Share Posted October 10, 2015 (edited) Maybe I should rephrase my oil post. I've only run 15w-40 and 20w-50 in two motors and they were taken care of. One of the two had over 220k miles. The oil pressure in the summer would be so fluctuating when coming off a 30min, 80mph interstate run that it was more comfortable to run the higher weight oil. Still, I've never seen bad results from either in terms of scoring from internal debris. From a few reliable sources of my own, including one of which uses to work for an oil manufacturing company as head of control, he informed me that there is little difference between "gasoline engine oil" and "diesel oil". If you look on many of the bottles, most will say "heavy duty" on the front and the details will only say "suitable for". The detergents can wash away the debris, but so can the same detergents in Synthetic. As a matter of fact, 20w-50 saved my engine AND my bearings when I lost oil pressure at 70mph on the interstate when my cam plug blew out of the head. If it wasn't for that, the engine may as well have been toast with as much stress as was put on the internals. When it comes to fluids on here, whether it be oil or tranny fluid or diff fluid, it's all a personal choice in the end. I'm running 10w-40 on my new motor only because it's brand spanking new and because I want it to have an easier break-in with better debris removal from honing and the like. However, I will likely switch to a Castrol 15w synthetic later because I like the protection of the thicker oil and it makes the engine feel MUCH smoother, mechanically. That's what I like and I trust. I have no problem with 15w or 20w in my older motors. Never had a problem before and that's my personal choice Good luck with the oil pressure. I would go with the sending unit first. Cheaper! Don't worry too much about the gauge. I've never seen a bad gauge, just a sending unit. Very common. If that doesn't fix it, you have much bigger problems and should begin taking things apart. - Charles Edited October 10, 2015 by nightwalkerancestery Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 10, 2015 Author Report Share Posted October 10, 2015 I've been told that 20w-50 is fine, just that the 15w-40 will tear the motor up. Where is the oil sender unit located and if the unit is bad, why when I start my car up does the oil pressure stay at half then drop to 0 when it gets warmer?? Quote Link to comment Share on other sites More sharing options...
Dad Posted October 11, 2015 Report Share Posted October 11, 2015 Because ats the oil gets warmer it gets thinner, then bleeds out from the extra clearances of worn bearings and shafts. Thinner oil will bleed out faster Quote Link to comment Share on other sites More sharing options...
nightwalkerancestery Posted October 11, 2015 Report Share Posted October 11, 2015 I've heard of lots of people running 15w. More than 20w anyway. No problems that I've heard that's directly related to oil weight. The sending unit is on the oil filter housing adapter. Right under the oil filter. It's the large canister/saucer looking thing. About two to three inches tall...About an inch and a half in diameter with a one-wire connector. As the engine warms up, the oil becomes more viscous (aka thinner). The oil exits all clearances quicker once it's warm versus when cold. When sending units go bad, they can either fail completely, or they can leak internally. The internal leak is a result from old diaphrams/o-rings inside that rot and don't hold the pressure properly anymore. This will cause it to show pressure, but read significantly low. This may be your case since you say there's no lifter noise when it reads no pressure. My red car's original unit was completely bad. Swapped with an old spare I had and it showed just under half on cold start. Bought five new sending units to keep around, as well as to use on my other cars eventually, and on a cold start the oil pressure reads a hair below the first max line. Once warm, it drops to 3/4 at idle. All on 10w-40. - Charles Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 12, 2015 Author Report Share Posted October 12, 2015 Thanks, i appreciate the info on the oil sender. Is it hard to replace it especially if its leaking like you say? Quote Link to comment Share on other sites More sharing options...
nightwalkerancestery Posted October 13, 2015 Report Share Posted October 13, 2015 They leak internally. Never head of one leaking externally. They're very easy to get out. It has a hex fitting near the base of it. I think it's 14mm (9/16"). Just wrench it off, watch for the oil drip, and screw a new one in. I like to use so Teflon tape about 1/16"-1/8" up from the end. Don't want Teflon tape getting in the oil system! - Charles Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 19, 2015 Author Report Share Posted October 19, 2015 Alright I'll do that. Any idea as to which brand oil sending unit to buy and how much they cost??? Quote Link to comment Share on other sites More sharing options...
2conquest Posted October 19, 2015 Report Share Posted October 19, 2015 Best of luck with your repairs. Im in the same boat but my car registers zero ats and maintains zero but it idles, runs, and doesnt show its getting hot?? Keep us updated, I'll be reading, troubleshooting and comparing just in case I might be missing something. Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 19, 2015 Author Report Share Posted October 19, 2015 Thanks man, ill keep you updated on progress. Im hoping it isnt main bearings, but they were replace by recall in 2001 so i dont think its them. Thanks, zach Quote Link to comment Share on other sites More sharing options...
Starfighterpilot Posted October 19, 2015 Report Share Posted October 19, 2015 FYI - I had two oil pressure sensors fail on me. When they failed they both read out of sight High no matter the engine temp or RPM. So I don't think it's a problem with the pressure sensor. Ya might want to pull the oil pump out and apart and replace the it's internal oil pressure relief valve Plunger and spring especially the spring. They wear out and loose tension. Also check the oil pump's internal clearances and for evidence of scaring or spalling per the FSM. For What It's Worth KEN Quote Link to comment Share on other sites More sharing options...
nightwalkerancestery Posted October 19, 2015 Report Share Posted October 19, 2015 Dude, I had two bad sending units on my silver car over time and both read either low or zero oil pressure. My current car came with a bad unit that read pressure, but was low and incorrect. What the sending unit sends to the gauge once it fails all depends on the type of failure. If it's a spring failure then it will likely read max pressure. But, if the problem is a diaphragm that is old and leaking, then it will read either low or 0. A sending unit is a LOT easier to fix than an oil pump. Call me crazy, but I go with the cheapest and easiest fixes first. If it doesn't fix it, call it preventative maintenance and move on. It'll eventually fail anyway especially if it's original. - Charles Quote Link to comment Share on other sites More sharing options...
Stealth R/T Posted October 26, 2015 Author Report Share Posted October 26, 2015 (edited) Im sorry, and am not trying to offend anyone, but these cars are the biggest pieces of crap. I honestly wish I would've kept my stealth because this car is a hunk a junk. The electrical systems are completely faulty, one vacuum leak and the car goes to hell, cant even find the darn brake componets for the cars, had to order the freakin pads an wait for them because they are an odd size. Nothing works correctly, the trannies are very rough and the cooling systems are bipolar. They have terrible power steering, miserable braking. The only thing this car is good for is doing donuts in a gravel culdesac because the rear diffs are locked in posi!! They accelerate like a diesel tracter, and have terrible understeer. These cars were probably really good when they were new or if they have been taken care of but stay away from ANY that show signs of abuse because you will pay through the mouth to find parts and have them replaced. If anybody is interested in buying a 1988 Conquest Tsi, with the shp rims and the lsd rear end please feel free to call me at 6363850241. the car is in decent shape, runs good (hasn't left me stranded yet) and drives well. Im just done with this nightmare of a car. I bet the Japanese are laughing at me now for trading for it. Thanks, zach Edited October 26, 2015 by Stealth R/T Quote Link to comment Share on other sites More sharing options...
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