So I would like opinions on this observation. The car is a 1994 Ford Probe GT (Mazda built KL03 V6)with close to 100k miles. I bought it about a year ago and for the first few months, it always started up just fine even in frigid WI winters. Then last spring, I started getting adventurous and switched to Amsoil ASL 5w30 (doped with LC). Soon after, it consistently began requiring two attempts to start up. I didn't think much of it - old car and all. However, I recently switched back to dino (Havoline 5w30) while AutoRXing and immediately noticed that it starts right up like a champ - first try just about every morning. The difference is obvious. I don't think the AutoRX is the factor because the change was immediate. In addition, the one and only time I ever heard the HLAs ticking was with the Amsoil. So my question is, what gives? I thought synthetics were supposed to be all-that-and-a-bag-of-chips. I had planned on going back to either Amsoil or GC after the AutoRX but now I'm not sure what to do. The Havoline is doing great but I'd like to extend my drains a tad and keep things squeaky clean inside the engine now that I've gone through the trouble of AutoRXing. Any thoughts??
Mazda KL03 V6 - poor starting with amsoil 5w-30 compaired to dino
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Hard to say. I'll bet the Amsoil and LC were doing some cleaning that may have effected piston seal. You put some new clean oil in and piston seal is improved and faster start. Why not suspect the LC? Was the car using any oil?
I've never heard of any motor oil affecting start other than cold cranking ability or dirty oil effecting piston seal.
Best to finish a double clean with AutoRx before saying any oil brand effects start (other than cold cranking)
I've never heard of any motor oil affecting start other than cold cranking ability or dirty oil effecting piston seal.
Best to finish a double clean with AutoRx before saying any oil brand effects start (other than cold cranking)
I'm not really sure of the book definition of "cold start." Here's better description. The double attempts would occur first thing in the morning or after work - once the car had been sitting for several hours. If the car had only been off for a few minutes - like at the gas station - it would start up fine with one attempt.
By the way, my experience with Amsoil ATF was just the opposite. It's great! Much smoother 1-2 sifts.
By the way, my experience with Amsoil ATF was just the opposite. It's great! Much smoother 1-2 sifts.
Maybe the higher dose of Moly in the dino clings to the engine better while the Amsoil all drains down to the sump when parked?
My Mazda 2.5 v6 seems to like dino as well.
My Mazda 2.5 v6 seems to like dino as well.
I have an MX6 V6, 90K+. It grew up on M1. I got it with 55K, and did an AutoRx soon after I got it. The HLAs quited down within 100 miles. After the rinse I continued to use dino and it worked fine. Now I have switched back to M1 and engine noise is greater than with dino. I dont think it is HLA noise, but friction gear. I never did experience starting issues though. You might want to try a different synth. I think the bennies with synth is worth the noise...
This is concerning
I have a 93 MX6 with the 2.5 V6 KL03 too, and am curently running dealer specified 20W50 dino oil. Was planning on changing to 5W30 or 5W40 synthetic but now am a bit worried
I have a 93 MX6 with the 2.5 V6 KL03 too, and am curently running dealer specified 20W50 dino oil. Was planning on changing to 5W30 or 5W40 synthetic but now am a bit worried
People are worried about synthetic oil causing hard starts? It is simply not logical nor is there any basis in historical fact. Like most things automotive there is a true root cause given all the facts.
Are you using LC on this fill? If so, then that's probably not it unless it also helped disolve a good amount of sludge into suspension with the Amsoil and increased the viscosity. Did the oil darken quickly with the Amsoil/LC. As far as noise goes, I've found the current Havoline to be a very good oil to quiet engines. My guess is the high moly contributes here. I also think it's an artifact and doesn't necessarily mean better protection but I like the effect.
I'm not trying to bash synthetics or amsoil here folks. I just wanted to post a phenomenon that I could not find mentioned after searching. I know it's not logical, that's why I posted it here. It doesn't make sense to me either but I'm not making it up.
Just to clarify. I only heard HLA noise a single time last spring and it happened to be with the amsoil after a cold start. It only lasted about a minute and went away - presumably as the oil got where it needed to be. I just thought I'd mention it as it seemed to go along with the over all issue - what ever it may be.
I doubt is was the LC because I didn't start using LC until about a month after I put in the amsoil. (once I discovered BITOG) I noticed the double-attempt starting before that.
The oil did turn a deep amber color but only after several thousand miles. I do have the amsoil BMK-11 bypass set up which I hope is filtering out junk and could be keeping the dip stick oil cleaner that it might have been other wise. Also, I had the valve cover off once last spring and apart from some varnish, it was quite clean inside - though I have no idea what the rest of the engine and ring packs etc are like. In general, the engine smooth and powerful and quiet. Sure, it's got a few miles and then some but I don't think the problem is with the car.
From those now worried about synthetics. Do a search, there was a person with a Mazda 626 (same engine and transmission) who posted a whole bunch of UOAs back in 2004. That person never mentioned what I saw.
I just wanted to post this odd observation and get advice on what oil to use next, not ruffle peoples feathers. I would like to go back to a high quality synthetic but now I'm sure what.
Just to clarify. I only heard HLA noise a single time last spring and it happened to be with the amsoil after a cold start. It only lasted about a minute and went away - presumably as the oil got where it needed to be. I just thought I'd mention it as it seemed to go along with the over all issue - what ever it may be.
I doubt is was the LC because I didn't start using LC until about a month after I put in the amsoil. (once I discovered BITOG) I noticed the double-attempt starting before that.
The oil did turn a deep amber color but only after several thousand miles. I do have the amsoil BMK-11 bypass set up which I hope is filtering out junk and could be keeping the dip stick oil cleaner that it might have been other wise. Also, I had the valve cover off once last spring and apart from some varnish, it was quite clean inside - though I have no idea what the rest of the engine and ring packs etc are like. In general, the engine smooth and powerful and quiet. Sure, it's got a few miles and then some but I don't think the problem is with the car.
From those now worried about synthetics. Do a search, there was a person with a Mazda 626 (same engine and transmission) who posted a whole bunch of UOAs back in 2004. That person never mentioned what I saw.
I just wanted to post this odd observation and get advice on what oil to use next, not ruffle peoples feathers. I would like to go back to a high quality synthetic but now I'm sure what.
Oh, I didn't consider this a bash - I am just frustrated at the lack of facts (ie hard to diagnose over the phone
)
I guess just get the engine really clean with AutoRx and try the ASL again.
I guess just get the engine really clean with AutoRx and try the ASL again.
You've got to start eliminating the stuff that is working. Lot's of things could be happening and in an inconsistant manner. You could have clobbered the O2 sensor and plugged up a pcv at the same time. This is a case of a mechanic with some troubleshooting ability vs a parts changer. The oil may not be the center of your problem(s).
There's no real problem now. I my observation. When I got the car it stared up with just one crank and continued to do so through a dino oil change at the local shop. Then went to amsoil 5w30 and it started to require two cranks when cold. I didn't really care until I went back to dino and boom one crank start ups were back. That's went I light went off and I started doing searches. Unfortunately, there aren't many people with this engine and forums devoted to the car are more focused towards ways to soup it up not wacky oil observations.
PS. The PCV valve is new.
PS. The PCV valve is new.
I don't think you can eliminate the impact of ARX and cleaning - I added some to my fill of M1 at 1500 miles after an oil and filter change and noticed a difference in low rpm response from a stop within 100 miles of driving. My car used to bog a bit as I engaged the clutch. Now I do not need to feather my clutch, even on slight hills. Since ARX was the only change, I can only attribute it to some internal cleaning.
I suppose. There are indeed several variables here. I just wouldn't have expected the ARX to work instantly - I thought it was a slow clean. And that doesn't really explain why the double-crank-starting began with the Amsoil. My thought is, and I certain could be wrong, that if it was a sludge related issue, I would have noticed it from the beginning when I bought the car and it would have gotten better over time with the Amsoil as it cleaned. The opposite occurred. The behavior started around the time Amsoil went in and ended instantly when it came out. I wasn't really tuned in to the issue last spring but I surely noticed the difference now that dino is back in (granted, with ARX.) The car is back to the way I bought is a year ago. (except for the transmission which is much better thanks to Amsoil ATF) There's also the LC variable but like I said, I think the behavior was occurring before I started doping. I'll be able to rule that out in a month or so when the ARX treatment is complete. I don't know what oil I'll use next but I'll add LC to it and see if the behavior reoccurs.
I kind of like hominid7's idea. Maybe the Amsoil flows a little too well while the dino leaves some film/residue behind which for some reason helps my particular car start up???? Is that all possible?? Is synthetic too good for this car??
Thanks for everybody's input here
blue94
I kind of like hominid7's idea. Maybe the Amsoil flows a little too well while the dino leaves some film/residue behind which for some reason helps my particular car start up???? Is that all possible?? Is synthetic too good for this car??
Thanks for everybody's input here
blue94
Valve seals are worn, leaking oil in the combustion chambers, allowing the plugs to foul-up when cold. PAO-based oils have a much higher flash point than regular dino oil. So, alittle oil leaks down the valves stems past the seal when cold. Dino "burns" easier than PAO/ester synthtics, thus you have the harder cold starts with synthtic than dino. It won't show-up if you take the plugs out and look for fouling - it's already burner off. I wouldn't worry about it and use any oil that keeps the oil from leaking on your driveway from that motor.
Gotta love it....sharp cookies here!
I guess the standard method to check for valve stem leakage is to have someone start the car while you stand by the tailpipe and watch and sniff for the slight wiff off oil smoke/smell
I guess the standard method to check for valve stem leakage is to have someone start the car while you stand by the tailpipe and watch and sniff for the slight wiff off oil smoke/smell
I just checked the Amsoil and Havoline web sites, and according to the published specs the Havoline 5w30 (in the car now) actually has a higher flash point than the Amsoil! Havoline is 232C(450F) while Amsoil ASL is 228C(442F). Is the theory still valid? Is PAO still inherently more burn resistant regardless of flash point? The idea sounded so good to me before I checked the data tables...
First of all those numbers are very close - flashpoint is not a precise number. Second, flash point really doesn't mean "burnability" (oxidizability).
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