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Hi, I have recently noticed my supercharged 2004 S2000 (with 48,000Kms) having some odd fluctuations in temperature. First some background info:
-The car had a small coolant leak from a small hose, but we fixed it before we saw any over-heating or any damage, we replaced coolant with Honda's own, and bled it. I'm currently running an AEM v1 with the modifry so I can see coolant temps, the normal operating temps should be at the dead center of the gage, or I think 10 bars out of the 20 in the AP2 (185-205 deg.).
Yesterday I saw it hit 2 or 3 bars hotter, but the car would go back down to operating temperature (10 bars) after I hear the fans kicking in, or even 1 bar lower in some cases. I know this isn't normal so I'm not using it right now. I took it to my trusted mechanic, he said it could be the after cooler radiator being dirty/clogged (exterior) and told me to bring it back later to clean it. There are no apparent leaks (coolant reservoir and radiator are both full), no bubbles in the coolant, and apparently no air in the system either (the heat in the car is searing hot), so I'm assuming this is not categorized as 'catastrophic'. I was also thinking the thermostat. The car does not seem to run hot while running faster than 40Kph. I just want to know if this is a true probable cause, and what other causes there could be.
That aftercooler radiator looks pretty much dead. It shouldn't cause that much an air restriction compared to say a large intercooler blocking the mouth of the bumper but it might be an idea to replace it as the fins look quite bent and probably not allowing much air through.
On the AEM ECU and probably on the flash pro you can change the fan settings to what ever you want. It may well be that the fans come on abit later than OEM.
Sounds like normal operation to me. And spending money to have your aftercooler cleaned which is unrelated to your coolant temps, would be you getting taken advantage of by either an incompetent mechanic or one that just wants your business.
Sounds like normal operation to me. And spending money to have your aftercooler cleaned which is unrelated to your coolant temps, would be you getting taken advantage of by either an incompetent mechanic or one that just wants your business.
This is not what I would consider normal operation, I know it's normal to see 1 more bar every once in a while, not 2 or 3 more. The mechanic's reasoning is that the aftercooler radiator is blocking a chunk of the engine's radiator, to me it seems somewhat reasonable, I don't think they would charge me much for cleaning it anyways, and if it really is dirty I wouldn't mind it getting cleaned, but I just want an alternate theory on why this would be happening, because where I live I'd have to order every part and it would take 1-2 weeks for them to get here, so I'd rather get the parts I need and do everything at once than to just going through different things, I hate to see my baby parked .
Originally Posted by markforrester99
That aftercooler radiator looks pretty much dead. It shouldn't cause that much an air restriction compared to say a large intercooler blocking the mouth of the bumper but it might be an idea to replace it as the fins look quite bent and probably not allowing much air through.
On the AEM ECU and probably on the flash pro you can change the fan settings to what ever you want. It may well be that the fans come on abit later than OEM.
Thanks for the reply, I might look into replacing the rad if it needs to be. I would check my fans, they seem to be running, but I have been running the same setup for a couple of years and it only started happening recently (actually, this week while I was bedding some brakes, and then it just kept happening), so I don't think there's an issue with a parameter in the ECU, which hasn't been touched after it got tuned.
So ive gathered that this change in your coolant temp only started right after you installed the supercharger? Or you had the supercharger on for a wile, and then it started running higher temps? You can get higher temp swings depending on ambient temps, if you are in stop and go traffic and definitely if you are running the A/C. But those are all normal. Do any of these apply in your case? Heat exchangers in my experience running a supercharger for many years, dont clog up, but rather the pump can get weak/go out or a kinks line, all of which you can verify by removing the cap on the aftercooler wile running and check that you see good movement/circulation in the system, if you do, its not being obstructed by dirt or any other failure, and that would again tell you that its not having any bearing on your engine coolant temps, so should look elsewhere. If you run the aftercooler system and verify you see no coolant moment/not functioning, then its possible IAT could be so high that it is having some bearing on inconstant higher engine/coolant temps, but you would also be noticing a severe drop in throttle response and power in that case as well.
Last edited by s2000Junky; 04-05-2018 at 12:34 PM.
So ive gathered that this change in your coolant temp only started right after you installed the supercharger? Or you had the supercharger on for a wile, and then it started running higher temps? You can get higher temp swings depending on ambient temps, if you are in stop and go traffic and definitely if you are running the A/C. But those are all normal. Do any of these apply in your case? Heat exchangers in my experience running a supercharger for many years, dont clog up, but rather the pump can get weak/go out or a kinks line, all of which you can verify by removing the cap on the aftercooler wile running and check that you see good movement/circulation in the system, if you do, its not being obstructed by dirt or any other failure, and that would again tell you that its not having any bearing on your engine coolant temps, so should look elsewhere. If you run the aftercooler system and verify you see no coolant moment/not functioning, then its possible IAT could be so high that it is having some bearing on inconstant higher engine/coolant temps, but you would also be noticing a severe drop in throttle response and power in that case as well.
The car has had the supercharger since my dad bought it in 2006 (and before, because he bought it like that), so it's been running a good while without any major issues, I'm now the one responsible for the car, and in the 3 years I've been driving it, I have only noticed small increments of 1 bar in stop-and go traffic under really hot weather and with the A/C on, but never more than that, so now I'm quite cautious of running it. I have seen somewhat inconsistent throttle response as well, as you mentioned, it seemed I had to go deeper in the throttle to get the car moving, so I might check that, now that you mention it, my car was in a small accident, that hit the left front where the water pump is located, but it seemed to be running fine at the time and a good while after, it's something worth looking into though, thanks!
I have seen somewhat inconsistent throttle response as well, as you mentioned, it seemed I had to go deeper in the throttle to get the car moving, so I might check that, now that you mention it, my car was in a small accident, that hit the left front where the water pump is located, but it seemed to be running fine at the time and a good while after, it's something worth looking into though, thanks!
Yep, always good to pop that cap off the aftgercooler once in a wile anyway just to insure good fluid movement and to check level, especially important if you have no gauges to monitor IAT. Electrical relays do go out, lines get kinked and pumps do get tired. If you were in an accident, something could have got loose, or pinched line preventing flow etc.
Yep, always good to pop that cap off the aftgercooler once in a wile anyway just to insure good fluid movement and to check level, especially important if you have no gauges to monitor IAT. Electrical relays do go out, lines get kinked and pumps do get tired. If you were in an accident, something could have got loose, or pinched line preventing flow etc.
One more question: Would you consider it safe to drive to the shop? Its only around 7-10 kms, but in stop and go traffic. I might check it myself, but I do need to diagnose to know what I need to order for the car, of course, I’d rather the mechanics look at it, just because of experience.
One more question: Would you consider it safe to drive to the shop? Its only around 7-10 kms, but in stop and go traffic. I might check it myself, but I do need to diagnose to know what I need to order for the car, of course, I’d rather the mechanics look at it, just because of experience.
IAT heats up quick in stop and go traffic, but i dont foresee any detrimental issue to your motor as long as you are light footed in your drive. But you really should be familiar and capable enough to check basic things like checking coolant flow in the aftercooler. Supercharged systems are pretty strait forward but there are a few things you should be hip on for checking to keep things on the up and up. Relying on a mechanic to do these regular checks for you is not practical and its an added cost, and chances are a typical mechanic isn't going to be familiar enough to properly check these things in a proper/systematic way unless they are really familiar with supercharged s2000's. You should be able to check all your fluids, check and know how to adjust your supercharger belt and be able to identify visually or audibly something amiss to prevent possible detrimental issues before they happen or get worse, or really you have no business running a forced induction system. The fact that you are catching irregular coolant temp is good, means you are at least engaging in the process.
You need an Allen wrench to unscrew the cap on the aftercooler (which is the box looking part of the intake right before the throttle body) and there is a cap right there on top, easily accessed. Make sure you see fluid approx 1.5-2 inches from the top from full, so there is enough room for the fluid to expand as it heats up, so checking proper level is first, then turn the ignition to full on, engine shouldn't need to start if wired correctly, but go ahead and start car just to alleviate that variable and make sure you see a decently brisk pace of coolant movement in the aftercooler, clearly showing that its circulating in the system. Report back.
Last edited by s2000Junky; 04-05-2018 at 07:34 PM.
Thanks, I will check that tomorrow after I come home from work and report back. I know the basic way superchargers work, I am just not used to working on cars myself, my S has forced me into DIYs though, so I’m learning a whole lot lately. I’m confident in my mechanics, they work with my uncles on their race cars, and one used to race an S2000 (as well as serve as a bridge for this S2000, lol), so they are not complete strangers to these cars, but most are not familiar with these forced induction setups, which is why I’ve had the need to learn how to work with it myself, and any guideance is well received!
04-04-2018, 07:11 AM
Engine running hotter than normal
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