Hi NAM'ers.

My modded 2002 MCS with 47000 miles on the odometer that won't start. I can't get a service appointment until Monday (I need to leave for MITM3 on Monday) and I'm wondering if the community can be of assistance.

I installed the Detroit Tuned Bypass Valve on my car last week. I decided to REALLY try it out by taking a 30 mile drive on a loop of highways that I really like. I ended up pulling over at a parking lot just before getting onto a really fun road because I was getting an SES light accompanied by high supercharger temps and a high idle (1500-2000 RPM).

The only reason that I know that the supercharger temps are high is because both of my SC horns have temp probes installed in them. The SC was spitting out 200-225 degree air when normally they're around 150-175 max on my car - even when I'm really on it. The car also felt like it didn't want to coast when I let off the throttle when entering exit ramps. It felt like the throttle lost modulation or the engine was dragging (getting 'boggy') a bit as I let off the throttle.

I reinstalled my stock bypass valve (after I read about some cases of elevated SC temps after installing the Detroit BPV). Unfortunately, now 97% of the time the car won't idle unless I keep my foot on the pedal and maintain some throttle to keep the revs above 1100 RPM. It stalls miserably unless I do this. During the VERY rare instances that it does idle, the RPM's are very unsteady and vascillate between 500-800 RPM's (it sounds like the engine is being revved mildly at low RPM and is about to sputter and die).

I don't outwardly want to blame the Detroit BPV. It is more than possible that another component may have let loose, I have an air/vacuum leak somewhere, my stock bypass valve is bad or a something else. ANY ideas or suggestions would help at this point I'm reaching zero hour and need to fix this.

Things I've checked so far:

1) Wiring harness at the throttle body is well connected. The car threw 2 codes for the throttle body (P0123 and P0222). I ended up replacing the throttle body and do not have these codes . . . presently.

2) I rechecked all my IC clamps and the clamp at the neck of the BPV

3) I inspected the plastic tube that goes to the supercharger from the throttle body and couldn't find any damage.

4) I replaced the metal crush gasket at the base of the intake manifold horn.


Things I'm wondering about:

A) Could something unrelated to the like a supercharger, belt tensioner, or AC compressor that finally died be dragging on the belts and stalling the engine?

B) Could another sensor have gone bad and is not allowing the throttle body to get correct readings to maintain idle?


Thanks for any help that you can offer! I really want to make it to MITM 3!!

 

Look at this again, was where my problems were. Wasn't totaly seated on
the SC intake, but looked like it was. Good luck.

 

How do I check if it's completely seated? Do I need to remove the radiator to get at it? -or- Is there a simpler way to check this?

Thanks!

 

Actualy, you, if you have a good sence of touch, can check the space between the valve & the tube.

What you describe really sounds like a big time air leak. How is the idle?

 

Hi all!

I did some visual rechecks of the car and an ECU reset today based on everyone's advice and then had a 3% moment of starting success where I got the car to idle. I then took the car for a drive. I still had that awful, scary idle as 'Blue (my MCS) and I started-off on our little MINI adventure, but it didn't stall. However, as the drive progressed, I could see the RPM's stabilizing at a nice ~800RPM! YESSS!!!

This may sound strange, but I think that the ECU had some 're learning' to do. I think the combination of way high intake temps combined with a replacement of the throttle body (which is now a dubiously replaced item) came together to REALLY screw with my ECU.

The car now starts like a champ. Let's see if will do that again tomorrow.

Thanks to all of you for your help and good MINI 'Car'-ma!" I really like how we look out for eachother in the MINI community.

Motoring-on . . .

-Clint

 

It's interesting you report high post-SC temps as a consequence of the BPV mod. There was a large thread about this a couple of years ago that confirmed this. I have run the BPV for the last 3 years (it was one of my first mods as I had a bad stumble at 3k). I too have temperature probes on either side of the IC and always see post-SC temps in excess of 200F. I am surprised you see such low temps (150F with a max of 175F). This would suggest the BPV mod contributes 50-75F to the intake temperatures--which is hard to believe.
That said, I most commonly see approaches below 20F, which suggests my intake system is working just fine.
What are your observations on approach?

 

Hi Dr. Phil.

I saw that you were in on the action pertaining to the debate over BPV's & elevated intake temps came up. Chad has a great product. If snappy throttle response and no yo-yo are your goals. That's your baby.

Your SC temps sound fairly high. I think that Jan at RMW has the SC up around 250F sometimes, but that's when he's on a track.

I have 3 questions for you:

A) Did you have the probes in place before you installed your DT BPV?

B) When you say 'approaches' do you mean within 20F over ambient air temp -or- 20 degrees under the temp at the SC?

C) What type of IC are you running?

To answer your question: More boost on hand = more heat. +50F-75F may be an extreme case, but I think that it's valid for my car because I'm running a 15%SC pulley w/a 2% crank pulley. I was doing comparative testing at the time I had said BPV on my car with the stock MINI air-air IC to compare it against the H20-Air IC that I typically have on my car (see my gallery). I now need to re-run those tests to take said BPV out of the equation because that mod obviously added a variable.

I'm running an H20-Air IC and I see 20-25F over ambient temp every day the temp is under 100 degrees and I'm cruising around town (30-50 mph). I see 15-20F on the highway and sometimes better in cooler weather.

Let me know about questions 'B) & C)' when you have a free moment.

 

Thanks for the information! I love talking IATs, even if it's only half the equation (I never want to ignore those all-important pressures). Yes, by approach I mean IAT-ambient. The general rule is that if you can achieve and maintain these under 20F you're in good territory, if you have any type of super/turbo-charged system. PARTSMAN and I have spent considerable energy working on the approach, and we see similar results--around 20F in normal traffic, around 10F in constant low load highway, and under 10F when times get good (winter, long optimal runs). I reported a maximum on-track approach of 35F from my last track day in 2007, which I was most pleased with.
To achieve these approaches I regularly see a temperature differential across the IC of over 120F, as high as 140F, which I think is truly impressive. I run a *system* that includes a DFIC with a gigantic scoop, a ram-scoop to the airbox, a modified intake duct system (thanks to PARTSMAN) and some M7 blankee. I feel that all this combines to make for a high performing intake system. That said, I can't tell you what the HP differential is, as I need a moving dyno (!)

I think the approaches you report are very impressive. Your experience with the BPV is very unfortunate, but I'm glad you're back with a working, performing, MCS!

PS I just remembered a conversation I had with Randy Webb, and he thought 200-250F SC-out temperatures were reasonable at high load.
cheers,

 

Mini-mon, glad that everything worked out.

Dr. Phil, should read Dr. IAT. I think you're past the masters part..........