Hello All,
I am once again having issues with my MINI. I thought I had put something back together wrong after I cleaned the intake valves but I took it back apart, cleaned and inspected everything, put it back together and it still runs poorly (misfires).

**Does anyone know if the Bavarian Technic scan tool can read the fuel rail pressure? If so, what is the value called? **

I looked for it but couldn't find it I have also contacted Bavarian Technic but the kept talking about ambient pressure and EGT, so they apparently didn't understand my question, even after asking it several times
Thanks for any help!
Howard

 

Well, I heard back from Bavarian Technic and they said "There are no separate values available for fuel rail pressure". Rubbish :(

Has anyone measured the fuel rail pressure? How? Obviously, I don't have a pressure gauge that goes up to 2000psi...

The only thing I can think to check it to compare my injection length at idle as well as the AFR and if the AFR is lean and the timing is long, it pretty clearly isn't getting the fuel pressure that it wants...or has a huge air leak, that I would think would increase the idle RPM enough to rule it out.

 

Hi Howie,

I'm using the Torque app on my Samsung III phone. I am able add a gauge using the app. by accessing the Fuel Rail.

I have attached two pictures of the app with the Fuel Rail gauge enlarged. The photo was taken with the engine at idle, app. 800 RPM.

Honestly, I'm not a tech, so I can't tell you if this is an accurate way to measure the output of the High Pressure Fuel Pump, but it does give a baseline to compare.

If I can help further, let me know.

 

Same app, I have mine set on kpa and I get around 5,000kpa which I believe to be around 725psi which is similar to what you get. Seems accurate enough when you accelerate it goes up and down. I know the r56 requires around 5000kpa to start.

 

Thanks guys! Now if only I had an Android phone... :( I'm pretty disappointed that my Bavarian Technic wont read fuel rail pressure, seems a little ridiculous. I have a friend that I think has Torque, I will see if I can get his help!

Unfortunately, I did already order the pump because I was fairly sure that was the problem (28 months earlier I had it replaced...conveniently just out of the 2 year warranty period...) but it would be nice to check it before I actually replace it, maybe I can return it, or sell it myself as new.

I got it from Waymotorworks: ( http://www.waymotorworks.com/ search for "pump"), best price I could find.

 

I'd pick up a cheap junky android tablet just to run Torque. It's too useful not to have. As for the fuel pump, even if it's not currently the problem, it will be eventually, so there's no harm in buying one now. :P

As already stated, the fuel rail pressure at idle is about 700PSI. It can reach about 2,200 PSI under high load. When my HPFP failed, fuel pressure held constant at about 60PSI. This also seems to be the pressure that the fuel system reverts to if the car goes into limp mode for reasons unrelated to the fuel pump.

 

Interesting info about the 60PSI, good referencing point. And to the OP there are quite a few Windows apps that also run bluetooth diagnostics. Failing that google bluestacks which runs a virtual android system on windows also works.

 

u238, that is kind of what I thought, if it doesn't fix the problem, then I will have a spare for when it fails again I think the pump in the fuel tank runs at approximately 75psi, so the 60psi you are seeing is probably just the in-tank pump pressure minus losses in the line and through the broken HPFP. Just a guess, but an educated one If it does fix the problem, I'm going to take the old one apart and have a look around. Does anyone know specifically WHAT fails inside the pump? Can it be fixed/replaced?

My friend does have Torque Pro and a Bluetooth OBD2 device, so I'm going to see if I can get his help. I also remembered that I recently bough a touchscreen monitor that has Android (I bought it mainly to use as a monitor for my wife's computer, I haven't really used the Android part of it much yet), so maybe I need to get my own Bluetooth reader and get Torque for myself, I've heard goods things about it from several people. That monitor wont be the most convenient thing in the world (it's 22" and no battery) but I have it, and hopefully I won't need to use it horribly often.

I've heard that there are very good bluetooth OBD2 readers and very bad OBD2 readers, any recommendations on which one to get? Or just buy an el cheapo and keep my fingers crossed that it isn't junk?

I've tried some Windows based, free programs and wasn't very impressed :(

Thanks everybody, for the help and info! I'll let you know how it goes.

 

This is the one I use. It's one of the most popular and it works great.

 

Ordered I still need to see if I can borrow my friends, because I'm impatient, I mean I need to know before I replace my pump...

 

You could get dashcommand for an Iphone, if that's what you have. I have little to no knowledge of it but there is a few guys on here who seem to like it. It has a free trial. If DC does show oil pressuer and temp I'd buy it. Those are two things missing from Torque.

 

Well crap. I checked my fuel rail pressure and it is around 700psi at idle and 1400psi off idle. Sounds like it is NOT my pump. :(

Any other ideas on what could be causing misfires? The #2 cylinder seems the worst, then #4 and then #3. #1 seems ok most of the time (trouble code wise). Idles terrible but doesn't usually die. Gets better at higher revs but is still very rough. We drove the thing home and it would do 50~60mph ok, even though it sounds terrible and doesn't have much power. It got oddly good MPG, upper 30's, but that could have mainly been due to the slow speed. A new spark plug in #2 didn't help. Swapping #'s 2 and 3 coils didn't seem to change the codes (I need to check one in #1). Unhooking any single coil didn't seem to make a big difference, if any at all. We were driving down the highway at something like 70 MPH and all of a sudden it started to run really rough. I'm pretty certain there are no leaks in the intake manifold. All of the connections in the intake tract look and feel secure. Im getting sadly stumped :(

 

One of the commonest causes of misfires on multiple cylinders is bad or contaminated fuel. Try filling up with some good quality high octane fuel and see what happens.

Another common thing is a timing chain that has skipped and is out of alignment.

However, there are LOTS of possibilities

 

Since this occurred after cleaning your valves, I would check all wire connectors and confirm that they are hooked up correctly.

After that I would compression test each cylinder. Maybe one or more valves is not closing completely, which would cause misfires. I compression tested my engine this past summer and had compression values of 150 lbs or higher, but it's also important that the compression numbers be very similar between each cylinder.

 

Yeah, I should check my timing chain. I changed it a couple years ago but haven't checked it for quite some time.

I had fairly recently filled up with gas but it was Shell 93. Unfortunately, that also means that my tank is fairly full, maybe 75% full I think. Maybe I can top it up and see if it helps.

What do you guys use to do compression tests? It doesn't seem like a normal compression tester would work, since the plugs are buried down in the head and have tiny threads. The only one I have is a REALLY cheap and crappy one. If I get a better one, I would definitely want adapters to be able to use it on more vehicles. It's not one for a motorcycle or something is it?

I think the only electrical connections that were unhooked were the MAP sensor, MAF sensor, whatever is on the turbo inlet for the PCV and throttle. It ran fine for 1.5 weeks before it all of a sudden started running funny. I've taken that all apart again and it still runs bad. I'm pretty sure that isn't the problem but it is easy enough to check. I'll make sure they are clean as well.

Now the big one. I did notice some wires that had worn through the insulation (!!!!) when I took the intake manifold off. It is the big bundle that runs under the intake, over the right side of the head and then branches off to a few places, including the coils. It had worn through the black armor AND the insulation on the insulation on the individual wires. It didn't look like they had contacted each other, I didn't see any black marks and they were still separated by a bit of distance. Since I found them, I wrapped each individual wire with tape and them added quite a lot of "armor" around the bundle to prevent it from happening again. Where they were rubbing was the air filter housing, so it was plastic. I was hoping that all would work when I put it back together and that I had caught it in time, but they could certainly be the problem. I did check the connectors at the coils and all 4 measured the same, either no resistance or the same resistance on all 4 and I also checked the resistance of the coils between each pin and they were all the same. I'm not sure what having them be bare could do and I don't have a bunch of spare parts that I can swap out to see if it fixes it. I will probably unwrap them again and see if any of them are for the coils. There were three, 2 colored and 1 black, so 2 powered and 1 ground, fun. Hopefully this picture will show up, it is still hard to see...

 

:(
This sounds very similar to what happened to me:
https://www.northamericanmotoring.co...cylinders.html
Burnt exhaust valve? I'm not sure if I should hope this is the case, so I know what to fix, or if I should hope that it is not, because it will be fairly expensive... The compression test is even more important now.

 

I haven't taken the head off yet, I'm close, but I saw it with an inspection camera. Burnt valve.

 

What brand inspection camera did you use? I want to buy one.

 

It was a Centech (Harbor Freight) that I borrowed from a friend. Looks like they are $60~$70, I think. It worked pretty good but I do wish that it picked up lower levels of light. It picks up its own light pretty good but I was hoping to see the light I was shining in the cylinder.

 

So what ever happened? Did you get the problem fixed? I am having a P0300 issue myself that just started and have been trying to find the source of the problem.

I did read one thread where a person cleaned their valves which resulted in the car running "junky". here what the person did was let the carb cleaner sit for too long and some seeped into the cylinder/combustion camber and sat there gumming it up a bit due to a valve being open a tiny bit.

 

It was a burnt exhaust valve. I rebuilt the head with all new guides and Supertech exhaust valves and did some porting on it and then had it coated by Calico Coatings Not cheap, any of it. And then when I got it back together my VANOS was bad (could have just been a dirty solenoid, I don't know).
It isn't hard to take the intake manifold off. I'd take it off and then be appalled at how much carbon is on your valves.
Exhaust valves are a bit harder to see but maybe once the intake valves are nice and clean then do a compression test and make sure that it is plenty high. Supposedly one reason for the burned exhaust valves is carbon build up that doesn't allow the valve to close all the way, which could be.
Not sure what the minimum from MINI is but I'd be worried about anything much less than 150psi. I think I'm up around 165psi, which is still less than I would like, especially with 10.5+:1 compression. With the bad VANOS is was crazy high, up around 220psi. They should all be pretty close, something like 10psi of each other.
Misfires can be from a lot of things. I think I had bad misfires when my timing chain was overly stretched. Could be a bad coil, bad/dirty plugs, quite a few different things but start with some of that and see if something shows up.