Just got started in the Mini world. I posted about the odd thermostat housing, as it did not appear like the ones in you tube videos I have seen (angled temp sensor v. straight). I have a leak there and have an ECS metal (and crossover pipe) on the way. However, I have other problems that I am chasing down. I have a miss at cold start up. Showing fuel pressure low. However, according to a carfax it has had a high pressure pump in the past. With todays crap parts, there is not guarantee that the newish pump as not already dissolved and gone back to nature. However, I am leaning toward pulling the junction box out and sending it off for a re-solder and fuel pump relay. the S clubman has 133,000 on the clock and like all the other little delicate parts on this car, I am sure that the board and relay are starting to feel the power/heat cycles. Has anyone used Houston Cars and Gadget on ebay. They seem to have a 100% rating. Any thoughts or recommendations contra the re-solder. Thanks in advance.
MoneyPit1969

 

Please provide more details.

 

2012 Clubman S no performance upgrades that I know of. I bought the car in late May. I don't have the codes in front of me, I will get them this afternoon. I pulled them with iCarSoft scanner. It showed a low fuel pressure DTC. The problem started as a stumble at startup that cleared up with driving. The idle and performance were fine after startup. Now the idle seems okay. however, it seems to have possibly gone into limp mode. No misfires are being detected at idle. When driving it has no performance. Under normal accel it is okay, but when accelerator is applied, no kick down and no boost. It does seem to be a fuel issue. Chicken and Egg sort of thing. However, I do not believe that the Fuse Junction Box has ever been out of the car. I don't want to chase fuel pumps if the relay and solder joints are bad. Thanks.

 

This preliminarily sounds more like an HPFP issue than a JBE issue. The engine would not start at all if the low pressure fuel pump in the tank wasn't working.

 

I am exploring all options on this. The reason I leaned to the Junction Box is that it has a relatively new HPFP. I can pull mine and have it reworked. However I was thinking of getting one on eBay and trying it out then sending mine if no joy. Does the ecm or junction box have to be reflashed if I switch to a different used junction box.

I will also be testing the hpfp this weekend to see if I have to drop the coin on that instead.

 

Some aftermarket HPFPs have notoriously short lifespans.

 

Thanks. I am trying to be a cheap shade tree mechanic. I can get a junction box for about $120 or have mine reworked for $150 vs $300-500 for the HPFP. I am just trying to avoid the inevitable I guess. Any thoughts on the reflash

 

I believe that a replacement JBE would require recoding, though at this juncture your car's issue does not fit well with a faulty JBE.

Reading the rail fuel pressure with your iCarSoft scan tool should quickly reveal whether the HPFP failed.

 

Hpfp is at nominal rail pressure = 1167psi ; rail pressure = 1170 at idle. At 3000 rpm nominal is 1456 psi up to about 1595 psi when reving up to 3k. There was a stumble and rumble at startup, but once started and running no code present after clearing them. The codes present were misfires, combustion gas present (I am guessing because of the misfires) and low fuel pressure were all stored codes. Those numbers sound pretty good for the HPFP I think?????

 

The rail fuel pressure is not low based on your readings, though I would have expected a lower fuel pressure at idle.
No fault codes?

 

There were a number of saved codes including low fuel pressure, exhaust combustion gas present, and misfires. After the first little stumble, at startup, it smoothed out fairly nice. I reset the codes and nothing, no codes reappear during that run cycle. I am going to crank it again in the morning to see what code it throws due to startup. As mentioned I cleared all codes and none were thrown during the run cycle.
I am not familiar with coking on the N18 valves. How much of a problem is that. Given the decent fuel pressure I am wondering if I have a valve seal problem. The pcv valve was whistling. I replaced the valve membrane and spring (not the whole valve cover) last week. Whistling stopped, but stumble didn’t.

 

Keep monitoring for BMW fault codes while running the engine and driving the car. Your Mini doesn't seem to have a fuel delivery problem upstream of the fuel injectors.

One possibility for stumble only after a cold start is a bad coolant temperature sensor. You can use your scan tool to check for abnormally high temp readings when the engine is cold.

 

I like to ask people that already have the Tshirt so to speak. The coolant temp sensor is where I started in a previous thread. I just got a new AL thermostat housing and cross pipe. It has a new sensor in it. I hate to take the intake off twice, but I may install those and see if it fixes it. If it is the coolant temp sensor it is definitely intermittent as it reads around ambient then up to 192 when the tstat opens. I think I am going to do the housing and pipe Friday afternoon. I can inspect the valves while I have the intake off. If all looks good I am going at the JBE.

 

Did you monitor the temp readings at a cold start where the engine stumbled? If not, do this to assess if the temp sensor is faulty and if the faulty readings correlate with the engine stumble.