Nope, sorry.

 

I'm with you- anyone know what kind of spring we can use?

 

My '04 MCS (TD79237 11/03 build) appears to have what you guys call the yo-yo effect. It's very mild, and I originally thought it was normal for a fly-by-wire throttle. Only seems to happen at initial tip-in of the throttle, usually in 1st or 2nd gear if I'm not trying to accelerate much. It's gotten to the point where I've adjusted my driving habits so that I accelerate a little faster to prevent the yo-yo.

Is there a way to figure out what software version my car is running, w/o going to a dealer (I'm in Alaska...no dealer nearby)? I'm not the original owner, but from the paperwork I have, it appears the car was recalled (I dont know what for) and I'm wondering if it was reprogrammed as a result.

I'd really like to get the yo-yo resolved, as it is mildly annoying when I'm trying to drive slowly...

Thanks in advance!

 

Hi there,

My 02 MCS has had the "stalling on cold start" issue since I bought it almost a year ago. Sorry, I don't know how long it was doing this before then.

Recently I have noticed a slight yo-yo and the acceleration is not as responsive as I would have expected.

It's been to a MINI service centre in the hope that they would update the ECU map, but I was told that it had thrown up a fault code relating to low fuel pressure at start up. They wanted to start on a "program" of swapping stuff in the fuel system, starting with the Fuel Pressure Regulator (FPR). They couldn't guarantee that this would cure the problem and mentioned the next step would be the injectors, fuel pump, wiring loom....sounds expensive and not very scientific.

I have a couple of questions for the experts on this forum:

1. Would a faulty FPR cause the fuel pressure problem at start-up? Surely the fuel pump would build up pressure as soon as the key is turned?

2. If it is the FPR would it also have something to do with the yo-yo symptoms?

I'm thinking of trying the VGS rerouting of the vacuum lines as an experiment, but I'm also thinking that perhaps in my case the root of the problem might be (as the MINI service guys said) something wrong with the fuel system. The FPR is connected to the vacuum system, would a faulty one cause the yo-yo and hesitation???

Dave

 

Hey I have a question regarding this..

I've done the mod and I like how it feels -- car even feels a little stronger.

Question is are you guys doing anything with the plastic tie-rod arm from the vacuum actuator? Mine is running into the spot it normally is connected to, and into the zip-tie..

Edit; N/M. Popped the plastic tie-rod arm back on after putting a heavier duty zip-tie on the bpv. I also modified an alan wrench to adjust the screw on the BPV to ensure that it's fully closing.

Seeing 1-2 psi just revving the engine now..

 

you need to take the BPV off to adjust it. tying to adjust it on the car will not work that great. if the butterfly doesn't hit the set screw at all it could wear a grove in the side of the bore and make a leak over time. once this happens you have to buy a new one. also while we have use the zip-tie to for several tests, we have not tested it for long term use and do not know what it could do long term. but i am guessing gas milage.

Chad
DT

 

Thanks for the info and advice. Only made about 1/6 turn on the adjustment, was mostly just curious to see the affect it had on drivability and if I would see any more boost at all, and I did.. I'm going to get a DT BPV soon.

 

Does anyone have the pics for this? They seem to have gone missing...

 

It's talking about using a zip tie to hold the BPV closed. with the car off, the BPV is closed. get in there with a long zip tie and go around the arm with the black plastic plunger from the diaphram and around the set screw. pull till tight, this will keep the BPV from opening. you will now alwasy be "under boost". i recomend this mod for everyone that does auto cross. (the day of the event)

Chad
Detroit Tuned

 

pm me your email and ill send you the pdf instructions Neufusion

 

I don't know if I have the Yo-yo problem, but I have some problem. Note, my car is modified, but has 15%, stock s/c. When I shift at relative low rpms, driving easy. when I let off the gas, the rpms actually increase a little. This makes smooth shifting very hard. I actually have to lift before stepping on the clutch, and sort of coast a little, in order to match rpms. This is a pain in the ***, esp. since I have a lightweight flywheel and little mass to keep the rpms up. I'd like them to drop quickly. What can I do? What is wrong with it? This does not happen, or I don't notice it when I am on it hard and shifting at higher ( 4 - 7000 rpm).

 

you don't have they yo-yo, you have a light weight fly wheel. as soon as you push the clutch in it takes all the force/drag away from it and it speeds up if your on the gas at all. just by taking your foot off the gas should do the trick

 

No, it is not the light weight flywheel. Lifting off the gas does not stop the engine from speeding up. There is a momentary (half second or more by my estimation) increase in engine speed when I lift my foot off the accelerator before the engine speed starts to slow down.

Like I say, I have to actually lift off for a second at least before the engine drops down to the speed it started at when I took my foot of the accelerator. Then I put the clutch in to shift.