AHHH ive tried everything... still not running right

[etxxz]

BOOYA@

now what did you do with the IX drive? e34 ix oil pan? how does it work out with the front axles that's wesome.. but an m52 is hardly worth the effort. you shoulda gone s50/2. Then again, pardon my ignorance, would the x-case be able to handle the power. that's awesome, e30 snowmobile ; |

[MattM]

FPR it was, when i plug the return line it runs like a champ

[bimmerteck]

yeah, unplugged the battery for 5 minutes after every change

That won't clear fuel trim adaptations on an BMW DME you actually need to go in with a scan tool and reset it.

[red911turbo]

Have someone keep the engine running for as long as possible while you slightly open the oil cap...Is there a large amount of vacuum trying to suck it back on to the valve cover?

[MattM]

yes, its in an IX:p

[etxxz]

damn canadian engines -.-


btw is that an IX 24v?

[MattM]

If the O2 sensors are wrong you will need to reset the fuel adaptations to see any difference. ;)


Use your GT1 and LMN what the fuel adaptations are for each bank. The O2 sensors are one of the few things that would effect each bank as a whole but independently of each other.

yeah, unplugged the battery for 5 minutes after every change

[bimmerteck]

i never cleaned the injectors, the engine came from a running and driving car, the FPR and some of the other bits including the DME, key, ews combo came from another.

im going to plug the return line tonight and see if it runs better...that will tell me if its the FPR or not

spark plugs are not new, but each was tested and have lots of spark.

All the gauges and lights on the dash work properly, the only CEL i am currently getting is for the fuel tank pressure sensor because it is not hooked up.

I have tried almost every possible configuration between the 4 o2 sensors i have... no noticeable difference in any of them.

I went through the vacuum system yesterday and would have a hard time believing i still have vacuum leaks.

ill see if i can make a vid tonight

If the O2 sensors are wrong you will need to reset the fuel adaptations to see any difference. ;)


Use your GT1 and LMN what the fuel adaptations are for each bank. The O2 sensors are one of the few things that would effect each bank as a whole but independently of each other.

[MattM]

i never cleaned the injectors, the engine came from a running and driving car, the FPR and some of the other bits including the DME, key, ews combo came from another.

im going to plug the return line tonight and see if it runs better...that will tell me if its the FPR or not

spark plugs are not new, but each was tested and have lots of spark.

All the gauges and lights on the dash work properly, the only CEL i am currently getting is for the fuel tank pressure sensor because it is not hooked up.

I have tried almost every possible configuration between the 4 o2 sensors i have... no noticeable difference in any of them.

I went through the vacuum system yesterday and would have a hard time believing i still have vacuum leaks.

ill see if i can make a vid tonight

[etxxz]

Lets touch upon the basics.

Your wiring is more than likely correct. The engine harness is self-contained. If you're running OBD2, your wiring is good. All the pins you cross in an adapter are for starting or for the dash. Maybe look at good grounds.

i would concentrate on mechanical stuff. Disconnect one spark plug at a time. Are they new plugs? Maybe you O2 sensor(s) is bad though it should still run. Can you post a video? Also reverting the fuel lines should have made a world of a difference, specially if they were already right. I still suspect vacuum leaks and something wierd going on with your fueling ie. bad injectors. Did you ever try to clean them? If so what did you do? I messed up some injectors trying to clean them. lol. had to buy 6 new ones. (ebay)

[MattM]

obd2 rail and fpr




correct wires going to it, i switched the fuel lines around for the hell of it and it made no difference...(i dont think it really matters for obd2 rails because the FPR is not built in...)


the fact that if i unplug the 3 "good" cylinders it runs the same on the 3 "bad" ones leaves me to believe all the injectors are working properly...

[etxxz]

^^ yes. The connector for the obd2 FPR is born from the same place where the rear O2 sensors come from and its a hella long cable. The only other connector in the area and long enough to reach is for the AIT (air intake temp), both of which the engine can run perfectly without. so the problem isn't the connectors.

Maybe your fuel lines are backasswards:
-Feed line coming from the filter goes through the open section of the regulator and feeds into the back of the fuel rail
-Return line coming from the front of the fuel rail goes to the Pressure Regulator of the FPR and back into the tank. Check it.

i don't even know if a car would run without a FPR.. maybe..

[Wanganstyle]

Ok, i pulled the intake mani off, tightened up all hose clamps, and checked all the wiring again.. EVERYTHING WAS GOOD

put it all back together and it ran no different(no surprise here)

so then i started playing the the coil packs

- all 6 have spark, checked each one.

- if i unplug the 3 assumed dead ones, the engine runs the SAME

- if i unplug the 3 assumed good ones, and have the dead ones plugged in, the engine RUNS THE SAME, and the other header gets hot.

So now i am 99% sure its a fuel pressure problem... question is.. how do i tell if its the pump or the regulator??

did you check all 6 fuel injectors the same way?

which fuel pump and fuel rail and regulator setup? obd1 or 2?

obd2 fuel rail (m52/s52) has a valve on the rail you can attach a pressure gauge to. This will tell you if there is pressure @ rail (and see if pump and FPR are working).

FPR is VERY stout, quite difficult to kill one.

[luckysnafu]

Had this same thought this morning. Matt you do have a fpr in place since the obd2 rail doesn't have one?

This. Make sure you have the wiring for this correct as well. There are multiple connectors that fit the FPR.

[bimmerteck]

If he can read codes there would be multiple codes thrown for having the O2 sensors switched. I had that problem when I installed new ones. The car still ran/idled and drove, just not very well.

It won't throw any codes until the fuel adaptation hit's the limits which can take a while especially if only running in very short spurts. If he could see fuel trim he will have one bank pegged one direction and one pegged the other possibly not at the limits yet. ;)