My car has just over 4200 miles on it, under about 5k RPM load, coasting, out of nowhere my check engine light started flashing, and I felt like I was driving a '70's era diesel truck. I shut the car off right away (Pulled over) and restarted it to find that there were no issues at all... I decided to give him a bit of a treat after that (Filled up with 3.5 gallons of 101 octane ). So I drove around for probably 15-20 minutes under varying loads (Normal driving, high speed driving, full throttle driving) to see if I could reproduce the issue, nothing.

Not sure where it came from, there was no warning at all. It seems like possibly the car misfired. My check engine light is still on and I think i'll take it down to Steve's Auto Clinic tomorrow to see what codes he can pull.

Just figured I'd post and see if anyone had an idea. Interestingly enough my DSC light was on as well, which I understand to mean that the car went into Limp Mode. Again, bizarre considering the milage.

Anyone have any ideas what could have caused this? Something to worry about or just a hiccup?



***Update Below, See post 13***

 

umm get the codes first but sounds like you *might* have overboosted too high for the MAP sensorto read it

 

That seems impossible given the situation. Honestly it was running like the MAF was disconnected, so what you said makes sense, but I wasn't really accelerating, I was just holding steady at partial throttle at about 5k rpm's. I was coming up to traffic so I didn't see the point in shifting, but I was too far away to really start using the engine breaking.

Also... if I haven't overboosted before at WOT wouldn't it be impossible to overboost at any less than that? Or maybe I don't understand it...

 

It'd be pretty hard to overboost given your mods and the warmer weather now. However it sounds like a faulty BPV to me.....

Happened to me as well, got both the CEL and DSC light on...but then they went away after restart. The code did pull though, and it was a faulty BPV. Sounds like an excuse to get a Detroit Tuned BPV nick.... :-)

 

Hmm 5k was a huge might on the overboost and given addition info rule it out, check your vaccum hoses yet? That or a BPV sounds likely but kinda suprising with you having a new BPV, of course the code is a HUGE piece of the puzzle lol

 

Yea, if it was a vaccum line it wouldn't have reset though? I dunno, I'm just gonna take it to steve tomorrow and have him run the code. We'll see from there I guess, anything before will just be speculation.

 

Thats how my car was running when I had a bad 61mm throttle body. Once I got that fixed the problem went away. But about 3 months ago this happened again and it was fatal, this is the time my piston blew a hole through it. Now $8000 later I will have my car back in a couple weeks. This all happend driving at 45mph in 4th gear.
Let us know what the results are
M

 

I ran her up pretty good after it happened and couldn't even come close to reproducing the issue. Interesting about the throttle body. I never got a chance to read up on exactly what happened to your car, could you link me to the thread? My throttle body is stock, and I don't plan on modifying it.

If it is indeed the bypass i'll have it replaced with the detroit tuned valve. I'm heading to Steve's Auto Clinic tomorrow to have him check it out. Mario are you coming to the SCMM meet this Sunday? I'm heading on a drive with a few audi folks afterwards. I have 2 tennatives with friends, but who knows where that will go, my friends are all flakes .

 

I posted it a while a go on Beanth the Bonnet I'm sure its several pages back.
No meet for me, I would like to go but I don't think it will be very fun with out having my Mini. Sometimes I forget I even own one, because it has been so long since I have even seen it.
Have you dyno'd your car yet? I would love to see the before and after once you get the new head.
M

 

No I haven't yet, but i'll be doing a baseline 2 pull test and the an after 2 pull test. The big thing right now is going to be what size injectors to run. I don't want to go with modified stock injectors (Inconsistant spray pattern) but we're not sure the 380's will cut it with the kind of power the head is putting down (With the mods I have, and based off the numbers longboard came up with, I think i'll be pushing 250 whp after proper tuning).

"He who shall not be named" has claimed that the new head is flowing so much that the engine sounds more like a scooby engine than a Mini. That tell tale pulsating engine growl . I'm looking forward to it, I just don't want to buy bigger injectors only to dyno again and see my AF goes wacky at 6500 RPM's and I need 400's :-\.

Since Longboard has already started going down this road, i've been advised to wait until they get the kinks worked out before I start experimenting. In the end I think i'll probably be going with his software too. The MTH, honestly, hasn't done a thing for me, and with the new valves rated up at 8k and beyond, i'd want software that would let the engine rev up into that range. I'll either start a thread of my own or start posting into longboard's thread once I get more information late next week. Depending on their schedule and mine i'll probably cruise down there and watch the install/get some impressions based off what I see.

I probably won't test drive his car, even though i've been invited to. I always feel weird driving someone elses car, let alone driving it quickly. I know I wouldn't want someone else doing that to my car !

 

I have a friend who was having his FPR valve slip off it would reset and then it didlight up if he pounced on it. IF yours was closer to not falling off completely but maybe one that was only off a little or had a tiny leak somewhere I could see it being hard to find without a code.

 

hmmmm....slight intake leak somewhere, map sensor/throttle body issue, most likely supercharger bpv valve sticking intermittent. see if you get a code 1688 -- (map sensor) bpv valve sticking will set that code.

 

Just got back from Steves. I was getting a "Random Cylinder Misfire" code. We pulled the plugs and sure enough one of them was fouled.

I'm getting the car dynoed next week so I'll see what I come up with for AF numbers. I remarked that the car could be running rich, but Steve thought that was unlikely.

His opinion is that since it was only one plug that was fouled it was likely just a bad plug. He gave me a whole new set of plugs and installed them out of good will and said he'd send in mine as defective.

I'm on edge now about where to go for my new head. Steve showed me a dyno today that was pretty darn close to what Longboard was getting (Baseline dyno at 184 whp, after the new head, he came back at 218 whp. 34 HP delta isn't bad, especially considering the fact that I can get Steve's head for about 900 less than the other head.

Decisions decisions...