Hello All,

Well to start off my wife and i just moved from Florida to Tucson, AZ. Well everything has been going great all up to a couple of days ago when the temperature here hit 110+. My wife came home and started telling me how horrible the car was running. After doing some trouble shooting and everything turning out and running correctly. I ended up talking to a couple of Force Induction buddies that drive STI's and Evos, and they said that it's the ambient air temperature that is causing the car to run sluggish.

So my question for all you guys driving your cooper S's in hot states what are you guys doing to get cool air in and through ur intercoolers?

The car we have is a bone stock 2005 Mini Cooper S convertible. She drives it to and from work about 15 miles, city traffic style, 5 days a week. We had to drop a grade in fuel to 91 octane, since AZ doesn't carry 93 octane at the pumps.

Thanks for your inputs guys!

Toy86

 

Heat soak can be an issue....till the car starts moving...
So I suspect You might have another issue making it worse....like a stuck bypass valve maybe...what is it doing?

 

The car is fine, and run good when it's the morning or late in the evening. The only time it runs like crap is when the car has been sitting in the sun baking all day. My wife says, that when she goes to accelerate the car doesn't want to go. It still accelerates, but very sluggish. I know cuz it's this Arizona heat.

So some of the options i've been thinking about and trying to reserch are maybe switching from a top mount intercooler system to a front mount but i don't think that will really matter cuz the air going throught is still going to be hot.

One of the best options we found was this water intercooler system like this: http://www.madnessmotorworks.com/mad...tercooler.aspx But as you can see it's not cheap.

Other things we're considering is possibly gettting the larger hood scoop, and possibly a larger intercooler with either the Alta, or DD air diverter.

We're just trying to find out how other cooper s owners are doing in hot states if they're even being affected.

Thanks for your assistance.

Toy86

 

I also don't think that the heat is the root cause of your poor performance. I used to live in Wichita KS, and it's routinely 100-110F there in summer and my '04 Cooper S never had any issue being driven there. Maybe the radiator cooling fan isn't working properly in traffic and the car is beginning to overheat? Look for things like that. You can actually get the little tach display to show you coolant temp while driving (search on here for a how-to), which might help with diagnostics.

 

2nd you might have something going on...
On 100° days I DO see a bit of lag for the first few feet of moving...then it is fine...
Folks have been driving the GEN1 S since 2002....
For alternate intercoolers, many have been tried....different locations too...all have drawbacks...even water to air ic or oversized/front mounted...namely made lag or longer time to recover from a heatsoak.....

 

Thanks guys for your inputs. I'll double check the fans and operating temperature again. The speed limits here in town are mostly 40mph, she does have to jump on hwy that is 55/(65 actual), and it's there where she feels the lag in power when she has to quickly accelerate up to highway speed. Once there the car operates normally.

Question for you guys, what are some signs of the supercharger starting to call it quits?

Her car does have about 112k miles on it and no major repairs done. We did have the power stearing pump changed under warrenty from Mini when were were in FL, and then we drove the car all the way from FL to AZ and it did great on the interstate.

Thanks guys for the info.

 

also check fuel delivery.
I lived in Phoenix for 30 years and when it gets that hot many cars get vapor lock. I have not seen anything like that in a MINI but you issues sure sound the same.
Just a guess.

 

[SIZE=3][FONT=Calibri]o.K. i didn't think anything about the fuel system. When you mean "Vapor Lock"; do you mean Detonation? When the fuel ignites before the piston hits TDC?[/FONT][/SIZE]
[FONT=Calibri][SIZE=3] [/SIZE][/FONT]
[SIZE=3][FONT=Calibri]How would i go about check the fuel system for Vapor Lock?[/FONT][/SIZE]
[FONT=Calibri][SIZE=3] [/SIZE][/FONT][FONT=Calibri][SIZE=3] [/SIZE][/FONT]
[SIZE=3][FONT=Calibri]Thanks for your help.[/FONT][/SIZE]

 

I don't know what happen to my last post but this should be ezer to read. lol

o.K. i didn't think anything about the fuel system. When you mean "Vapor Lock"; do you mean Detonation? When the fuel ignites before the piston hits TDC?

How would i go about check the fuel system for Vapor Lock?

Thanks for your help.

 

If I was caught in that situation first thing I'd do is probably reset the ecu. Simply unplug your battery and let it sit for 30 mins.. You'll lose your radio settings and all but it will allow your ecu to readapt to the environment and your driving style.

You did go from sea level to 2k in altitude.. Cars with forced induction dont usually suffer from the altitude loss unlike those that are naturally aspirated but who knows. Even though the heat might the major issue this procedure could help.

 

Vapor lock is basically boiling fuel....
can sometimes happen if you are using "winter gas" which is more volatile to allow better starting in hot weather...like a car was filled on a warm winter day..stored...and then driven in HOT weather...or you are using up some old fuel from a gas can out of season...
gas stations typically change their blends spring/fall early enough to prevent issues....
How many miles on the car?
Air filter been changed? I know the mini's stock location can get gunky fast, and when I lived in Colorado (not with my MINI), I would go through filter pretty fast from the dust....Spark Plugs?

Is the car 100% stock? Any mods?
Any warning lights?

A SC can made some noises as they fail...most common way to fail is losing the oil in the water pump PTO, then the gears wear quickly...water pump stops. Not an issue here...next is the snout bearing wearing...but usually a sound...lash..kinda like loose gravely sound...also not an issue (apparently). the final wear is just loss of boost through rotor/Vane wear...but should be a gradual loss...and a few folks have gone 200k+, so unless you are running without a filter, I kinda doubt it.

I might be tempted to use a can of sea-foam through the PCV system to clean up some sensors, etc.....

 

OP. Nope What you are experiencing is just normal AZ summer driving. Both of my 03 are the same way and everyone I know with a first gen talks about the same thing. I'm up in Tempe and we're usually about 10 degrees hotter. It sucks but about the middle of October you'll be loving life again.

 

Zippy is correct but in AZ it can happen with summer gas with air temp is 110 and under-hood temp is !!!!

Mostly happens with start-up becasue gas in the lines have vaporized and the pump does not work on gasious-fuel, or is working aginst vapor insted of liguid. The gas vapor compresses and does not move the liquid fuel.

Prolly what the other AZ guy responded, just hot less dense air from the heat.

 

Hey guys thanks for the helpfull hints. Meboosta, you made a great point about the sea level thing; that could be the cause along with the lower octane gas from the west. OldGameFreak thanks for input about this AZ heat man, you really put the worry behind us.

As far as the Vapor Lock thing i did some research on this and i highly doubt that the fuel is vaporising before it goes through the injectors.

Just to give you guys some back round i am a mechanic foro the air force, and i just got done discussing this same situation with my coworkers and we came up with that the probably reason that the car is performing the way it does with these hot heat days, is that the Hot air is thinner, and that the car's computer is compensating for the lack of air by adding more fuel cuzing the engine to bogg down under acceleration. Once the car gains speed, and the air flow increases through the intercooler, and cools the charged air, the Air/Fuel mixture corrects itself and the car runs fine from there on, until you hit stop and go conditions again.

Some of the things that i'm going to try and do to fix this situation is i'm going to up grade the radiatior fan, get a better air diverter to replace the stock one. If that doesn't work well probably up grade the whole intercooler system to Water/Air.

I will continue this post as we do the upgrades to combat these hot Arizona days; to help out other Mini Cooper Owners fight the heat from these hot states.

 

I wouldn't bother with the radiator fan. I run a scan gauge and my water temps are usually just under 200. It can be 118 outside and I never get hot (WATER TEMPS). It's going to be all about cooling the inlet air temps. If you really want to cool things off just go with a meth injection setup.

 

So I live in Zimbabwe, Africa got a 2004 pre face lift r53. Hot 30 to 35 degree dry Savanah heat. Burning hot 🔥. Anyways
I feel the exact same issue only when I'm pushing it and stop and go traffic.

I'm thinking along the lines of doing a run on a very hot day and deliberately track data and move from there. But im thinking of a couple of ideas. Bmw 850w heavy duty fan , water to air intercooler and methanol kit.

I believe its the inlet temps, and it needs to some how be cooled. Thats why I believe meth injection is key combined with the other 2. Maybe even having a second tune that is specific to hot days and altering fuel maps and AFR. The thing is we want our cars to be run all day long, pushing it and pulling it.

Only issue with my suggestions and ideas is the price and budget you need for such a thing. It would cost roughly 2.5k to install and with a tune. Yet a golf gti mk5 is around 3 to 5k. Golf 6 gti is around 7.5k to 9k so at this point we gotta look at the numbers and if it makes sense.

 

Engine controller seeks to keep air/fuel ratio in the 14.7:1 area because with a healthy engine with this air/fuel ratio is produces exhaust gas that is most efficiently processed by the converter. So it will not add more fuel, but less, because there is less air. However, a turbo-charged/super-charged engine will still be supplied a good amount of air -- vs. a naturally aspirated engine -- and the engine controller will keep the air/fuel ratio in spec.

I have driven in some hot climes including southern AZ -- 116F -- and even up north to the west of Kingman AZ -- 119F -- and elsewhere where temperatures are 100F+ and in various cars and really didn't experience any issues. Oh, the 1st time -- in that 116F heat -- the car's temperature gauge needle went into scary territory but the engine was fine. And the same for other engines in various cars I have driven in high (>100F) ambient temperatures.

While 91 octane is probably not ideal it is not the problem. But whatever gasoline you buy you want it to be fresh. So be sure to buy from a busy station.

If the lack of performance is real and not normal there is something going on -- to state the obvious -- but it is not directly due to the heat. My inclination is to suspect a fueling problem probably -- if I had to guess and I do... -- due to a weak fuel pump. This assumes the engine is in good tune. That the plugs are reasonably fresh and the right plugs and have the correct gap. The engine air filter is not too dirty. These are small engines but with a turbo/super-charger consume considerable amount of air compared to the engine displacement and the engine air filter will get dirty. Hate to admit it but several times I let an engine air filter go too long -- one time with a naturally aspirated engine and one with a supercharged engine -- and after replacing the air filters the engines ran noticeably better.

 

On the low end, try running a sponge air filter, they breathe a lot easier and are good for hot wx. The combination of a dirty air filter + lower fuel octane could actually be the problem, so push a little bit of Seafoam through that topside vacuum line to shake some of the carbon build-up off of the valves and you may be back to normal. How are the spark plugs doing btw?
On the high end, your harmonic balancer may be taking a dump on you or like ZippyNH said, your bp valve may need replacing as it sounds like it's lagging under boost. Just guessing here but when problems start I find it best to imagine the worst case scenario to soften the blow to my wallet.

PS. the desert will make your engine bay dusty af which may require you to buy a pair of new air filters, so you can easily swap them out more often than usual.

 

it isn’t that at all

no issues here on115 degree days after soaking in the sun all day. Other than the interior being hot AF.

id be looking at changing the fuel filter and maybe pump or FPR as it sounds like an issue with fuel evaporation, aka vapor lock or a low fuel pressure when hot scenario.


but also… the battery. Heat is as bad as cold on them.

 

What Temps are you seeing you think are causing your issue ? I've seen intake Temps on my cars in 180'F before and spiked at over 200'F and I had almost NO power loss still. I mean yea some but far from enough for concern. And those were EXTREMELY HOT iat's because of extra boost and pos ebay ic I was testing .
imo , check the intake Temps while driving . A simple 3$ obd2 dongle and any free 0bd2 monitoring app will give you the ability to view iat and other parameters that may better direct you towards your issue..
Is the car an auto ???? I could see bad clutch bands or sticky solenoids causing a delay off the line , exp when hot.

 

A dry 35 C day is actually a nice mild summer day , like almost late September October November / fall weather. Like it’s a good day to go cut the grass, and do other outdoor work because it’s so cool out.


fyi, we’ve been as high as 45 C, mostly around 40c for 3 months consecutive, and I haven’t seen temps as low as 35 C since roughly early may.

so you don’t have any sort of high ambient heat issue causing high intake temps or issues.

 

I hear you, my fuel pump just got changed and boy its back to pulling. Haven't took it for long enough run to see if it's completely solved my issues. I'm happy for now , but let's see. Try to get some custom head work done, open up the supercharger a tinny bit, custom cam and a tune. I want to be able to drive this thing long haul with no heating issues. Maybe even a 550i fan, radiator , etc wish me luck