Bimmerfest BMW banner

1 - 12 of 12 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
Hello everyone.

155k 530i after many hours of regular operation I have experienced hard running, stalling even at WOT.

Turning off and re-starting helps.

So far over the last several months I have replaced three COP's after reading codes. This last time after replacement I experienced about 800 miles of a perfectly running M54.

Yesterday though the issue came back.

I read the codes again and have transcribed them below.

PO1 71 System too lean bank 1
P1 085 Fuel control limit mixture too lean (bank 2 sensor)
P1 083 Fuel control limit mixture too lean (bank 1 sensor)
P1 343 Misfire cylinder 1 with fuel cutoff

This morning it started and appears to be running normally as I have not had a chance to drive it.

I have had the car for about a year and have driven about 5k.

Was thinking it could be the fuel pump or filter.

Thoughts?
 

·
Wingnut
Joined
·
3,724 Posts
whats the fuel pressure at the rail? the misfire cyl 1 could be a coil, try swapping it with another cylinder and see if it follows. lean codes indicate a possible vac leak, id check for them. taking a look at live engine data (fuel mixtures) will give you more of an idea whats going on.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #3
Thanks for your reply.

The cylinder 1 COP was replaced this month with a brand new OEM Bosch COP. Easy enough to check. I cleared the codes and as of yet none returned.

I will check the FP.

Its running normally right now.

When it happens its always very hot like 90 F.

Thanks again
 

·
Wingnut
Joined
·
3,724 Posts
these filters rarely if ever clog...check the pressure at the rail first
 

·
Registered
Joined
·
56 Posts
as suggest check the fuel rail pressure ,but sounds like either a faulty fuel pressure reg or the fuel pump is on the way out, also make sure u are using good fuel from a reputable supplier as bad fuel can cause these issues.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #8
Of course the rough running issue has not recurred so there has not been a chance to check the fuel pressure yet. I am ready with the gauge in the truck.

Now though I have a more pressing issue that I need some more excellent advice for.

A week ago yesterday I was 10 miles or so from the end of an over 200 mile trip. Car running nicely on cruise at 3k rpm 80 MPH for nearly the entire trip.

All gauges appear normal when suddenly on the cluster appears coolant temperature high and gauge is in the red though not pinned. Shut down the car immediately and coasted to the shoulder. Called AAA.

Should have never taken the car as I noticed some wetness coming from under the car before I left. Live and learn.

The water pump is toast. Besides the water pump and associated belts and pulleys if necessary I need advice on whether I should repair other small leaks such as the oil pan gasket and maybe a refresh of the power steering system.

With 156k are these other fixes worth it. I enjoy the car and would hate to see it go.

I am looking at around $2,000 if I do everything.

Thanks in advance for any thoughts and recommendations.

Brad
 

·
Registered
Joined
·
331 Posts
Of course the rough running issue has not recurred so there has not been a chance to check the fuel pressure yet. I am ready with the gauge in the truck.

....

Should have never taken the car as I noticed some wetness coming from under the car before I left. Live and learn.

The water pump is toast. Besides the water pump and associated belts and pulleys if necessary I need advice on whether I should repair other small leaks such as the oil pan gasket and maybe a refresh of the power steering system.

With 156k are these other fixes worth it. I enjoy the car and would hate to see it go.

I am looking at around $2,000 if I do everything.

Thanks in advance for any thoughts and recommendations.

Brad
What steps did you take to determine the WP was bad? These cars are prone to coolant leaks and many people overfill the coolant reservoir which likely exacerbates coolant system issues. Many parts that could be issue like expansion tank, radiator, nipple on top radiator, etc. If you are sure its WP, you may as well do thermostat while you are in there. Many people even replace WP pulley, but I have stuck with the original.

Replacing the WP and belts is pretty cheap and easy to do yourself, as for pulleys, you remove them and repack them with fresh grease. Common oil leak area is from the Oil Filter Housing on drivers side of engine, best to clean engine to really determine where the leak is. At this point in cars life it is probably due a VCG change as well...look for oil on the heat shield over the exhaust manifold to confirm VCG leak.

These cars will nickel and dime you to death if you don't know how to take care of minor things.

I helped out a subordinate this weekend by replacing bowden cables in both rear doors, replacing O2 sensors, clearing codes (new O2 sensors knocked out 6 of 10 codes, he still appears to have a vacuum leak which is likely in his CCV system), and determining that his grinding engine noise is not coming from engine or WP (as stated by so called mechanics) but is coming from his alternator (can't beat a big old diesel screw driver as a stethscope), removed rear tail light to tweak, clean bad brake light.....all this would have cost him big $$ at shop...but can be done at home for cost of time/parts.

My car is 194K and runs smooth as top...but you have to stay on top of maintenance and not let it pile up.
 

·
Registered
Joined
·
567 Posts
I am betting you have a vacuum leak. Borrower or buy a smoke tester. It is a great tool to to have as these cars age. I recently found a large leak at the throttle body gasket.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #11
Thanks for replying.

The indy that the car is at now did a cooling system pressure test and they said that liquid is pouring out of the water pump.

Unfortunately this car is at another place not near where it is easier for me to work on.

Xray feel free to stop by if you are near in SW Florida I'll supply everything you need as well as a third hand.

Thanks eff for the smoke test tip. Its a great idea.

Brad
 

·
Registered
Joined
·
331 Posts
Thanks for replying.

The indy that the car is at now did a cooling system pressure test and they said that liquid is pouring out of the water pump.

Unfortunately this car is at another place not near where it is easier for me to work on.

Xray feel free to stop by if you are near in SW Florida I'll supply everything you need as well as a third hand.

Thanks eff for the smoke test tip. Its a great idea.

Brad
All rubber/plastic components on these cars will become brittle crack break, I concur with effduration that you should eliminate vaccum leaks before deep diving into other areas. The CCV lines under intake manifold are a prime suspect as well as intake boots.

I will be looking at these same areas before digging deeper on my co-workers car.
 
1 - 12 of 12 Posts
Top