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DISCUSSION => Engine + Driveline => Topic started by: jakeb on December 13, 2010, 06:04:23 PM

Title: no start, plugs fouled within seconds
Post by: jakeb on December 13, 2010, 06:04:23 PM
I am working on a m42 swap into a 2002....this is the 4th one I have done and the other three have started without trouble.  This one not so much....

Here is what I have checked and what is going on....

92 e36 m42, e36 automatic trans, e30 intake manifold

It will start briefly and idle very very very badly, normally buck and shaking all over the place.  Then quit....

Here is what I have checked/done so far....
fuel pump runs (both a prime and when cranking)
replaced Cam sensor with a spare
checked crank sensor (ohmed out, also when connected I have spark when discoed there is no spark)
good spark
all four injectors are firing (checked by pulling the intake and cranking while the intake was spraying onto a box)
swapped in a different fuel pump (known good)
swapped in a different Fuel pressure regulator (unknown condition)
Tried three different AFMs
swapped in a different ICV
checked compression, around 180-190psi on all 4 cylinders
swapped two different ECUs


So it will start once but runs very very badly, bucks, kicks, shakes all over, and then stalls violently.  Not sure how else to describe it.  

When I pull the plugs they are wet with gas and BLACK, to the point they look very fouled.  What could be causing too much fuel?  Also after cranking and the little bit of starting it does do when I pulled a plug right away I got black smoke coming from the spark plug hole.

The only things I haven't swapped out are
injectors
coolant temp sensor
TPS
crank sensor (but I know it works)
the entire engine (ha)

any guesses?  The history of the engine is unknown......it was pretty black looking inside.  Out of all the engines I have swapped this one looked the worst inside....just lots of burned on oil.

Not sure what to check next....  I do another another m42 I could swap in.  I also have another m42 that I could swap injectors with
Title: no start, plugs fouled within seconds
Post by: DesktopDave on December 13, 2010, 07:42:48 PM
You checked the cam timing, right? If the motor is that bad, might be a cam skipped a few teeth or the crank is out.  Other than that, I'm not sure what else to say.  Sounds like you've already checked everything else out.
Title: no start, plugs fouled within seconds
Post by: jakeb on December 13, 2010, 07:57:59 PM
I have yet to check the cam timing....that is something on the list tho.  I think I will check that before I swap the intake off my other car.  Is the process to put it at TDC and then the back of the cams should be flat?

The other thing that I will mention is that I did have to lengthen the injector harness because it was a little short for how I have to route everything.  Could that cause an issue?  I can't see that being a problem....  the wires were solder and shrink wrapped, I checked the resistance back to the dme connector and think I got below 1 ohm
Title: no start, plugs fouled within seconds
Post by: KenC on December 13, 2010, 08:28:29 PM
Are you getting spark on all four cylinders. When the engine shakes, it's usually because one cyl isn't firing.

Too much fuel = bad FPR
Title: no start, plugs fouled within seconds
Post by: jakeb on December 13, 2010, 08:34:11 PM
Only tested at one spark plug but I could check the others sometime.  I ordered a FPR and it will be here thursday so I will have to wait and go from there.  Or swap another intake on tomorrow...

Odd that two FPR could be bad, but it is possible I guess.
Title: no start, plugs fouled within seconds
Post by: KenC on December 13, 2010, 09:02:30 PM
Yeah, definitely check all the plugs and report back.
Title: no start, plugs fouled within seconds
Post by: colin86325 on December 13, 2010, 09:57:43 PM
Check for a bad intake manifold leak. Make sure nothing such as a wire has dropped between the mating surfaces.
Title: no start, plugs fouled within seconds
Post by: jakeb on December 14, 2010, 09:25:09 AM
Quote from: colin86325;99610
Check for a bad intake manifold leak. Make sure nothing such as a wire has dropped between the mating surfaces.

not a bad idea.....the intake on the engine is not the same one that came on it so maybe one of the little bosses is holding things up.  I also remember hearing it hiss a bit after starting and dieing....from somewhere under the intake

I'll pull the intake after work and check that.
Title: no start, plugs fouled within seconds
Post by: jakeb on December 19, 2010, 02:51:58 PM
still the same issue....

I pulled the intake and made sure all mounting surfaces were clean...and then reinstalled the intake, there should be no air leaks now.

checked the cam timing.....I don't have either of the tools but with the first cylinder at the top of its stroke the backs of the cams are flat and both of the first lobs are point in as shown in the bently.  Unless it is 180 degrees out but not sure how that could happen....  I could not get the little plug out where you put a pin to the flywheel/flexdisc to know it is at tdc.

I checked and I have spark at all four plugs when cranking....

Still no start....it will start for a few seconds but runs very very poorly.  

Here is a picture of a plug after cranking for a little bit, it is soaked with fuel...then after 30 seconds it is evaporated and black.
(http://theguestroom.net/karen02/plug%20%28Small%29.JPG)


I am not sure what to check next.....

I have another intake I could pull off my own car and swap on (to test the injectors and regulator).  I have a new regulator I could swap on......  Another thing I notice is that the plug sounds the same all the time...I thought I have noticed on others that after pressure has built up the sound of the pump changes a little bit.

anyone have any ideas?

I actually have another m42 I could swap in but would like to find some reason why it's not running before I do that....if the engine is bad I will swap it for another but...so far timing seems ok, I have compression....
Title: no start, plugs fouled within seconds
Post by: KenC on December 19, 2010, 03:51:30 PM
Swap in your new FPR, add a LITTLE oil to each cyl and try again.
Title: no start, plugs fouled within seconds
Post by: jakeb on December 19, 2010, 05:05:08 PM
new FPR in....cleaned and torqued plugs, it did start but ran about the same as it did before.  It may have ran a little bit better but not really.  Pulled the plugs....soaked in fuel
Title: no start, plugs fouled within seconds
Post by: jakeb on December 19, 2010, 05:24:39 PM
could it be something with the automatic trans?

I am really at a loss of what to do next.
Title: no start, plugs fouled within seconds
Post by: tom d on December 20, 2010, 12:52:22 AM
you should be able to hear the injectors cycling. sounds like they are staying open.
Title: no start, plugs fouled within seconds
Post by: jakeb on December 20, 2010, 08:00:11 AM
When I pulled the intake and set it against a box and cranked the injectors fired and then stopped when i let of the key....

When I back probe the injectors I get 12v at both sides of the connector but that might be normal when the dme isn't grounding the other side...
Title: no start, plugs fouled within seconds
Post by: jakeb on December 20, 2010, 08:53:21 AM
One thing that I have done different with this swap compared to others is that I had to lengthen the fuel injector harness to work with the intake I have to use.  So....I cut, added wire, soldered, and heat shrink-ed the connection on each wire.  Not sure why that would cause a problem but it is possible I guess....

I am at a loss.....
Title: no start, plugs fouled within seconds
Post by: jakeb on December 20, 2010, 11:10:07 AM
tried unplugging the trans computer...no help.
Title: no start, plugs fouled within seconds
Post by: DesktopDave on December 20, 2010, 01:47:17 PM
Did you tone out the harness, just to see if your connections are all tight?  Any possibility of cross-wiring?
Title: no start, plugs fouled within seconds
Post by: jakeb on December 20, 2010, 04:22:45 PM
yup...  I have checked and triple checked from the harness back to the dme connector.  I swapped the injectors for another set I found...the ones in it now are e36 injectors.  cleaned the plugs, hooked it all back up and it did run for a little bit longer, poorly but it did run.  Then stalled...

Thought I would check the o2 sensor...black as could be and wet with I assume fuel...swapped in another one.  No go....

Pulled the downpipe thinking maybe there was some restriction and when I cranked it I have flames coming from the exhaust manifold....it started for a few seconds.  Cranked again and nothing....

It is almost like when the fuel is going in it is building up so much compression it cannot overcome it.  It is sorta hard to explain.

Unplugged the AFM....no go, the dme did give me a fault for it being unplugged tho
Unplugged the knock sensors....no help

I am thinking of going to pick up a leak down tester and checking to see if the valves are bent and thus leaking.  Would an engine still build compression with bent valves?
Title: no start, plugs fouled within seconds
Post by: dj91318is on December 20, 2010, 06:21:07 PM
Quote from: jakeb;99769
One thing that I have done different with this swap compared to others is that I had to lengthen the fuel injector harness to work with the intake I have to use.  So....I cut, added wire, soldered, and heat shrink-ed the connection on each wire.  Not sure why that would cause a problem but it is possible I guess....

I am at a loss.....

Swap what?   Lengthened Injector Harness?  Sounds like the fuel injectors are all open never closed, Short / Signal to stay open all the time, some how.

Wish I could tell you what to check.

WOULD A CLOGGED return FULE LINE CREATE ENOUGH PRESSURE TO OPEN THE INJECTOR'S? or the inlet and return fuel line are backwards on fuel rail / FPR.
GL dj
Title: no start, plugs fouled within seconds
Post by: jakeb on December 20, 2010, 07:35:04 PM
This engine is in a 1973 BMW 2002....
here is a pic of what I am working on....
(http://theguestroom.net/karen02/IMG_2479.JPG)

I do have another harness I could put on and see...

I just went out and bought a leak down tester and it is coming up with around 20%....  not sure if I trust the gauge on it so I need to get a little different gauge tomorrow.  But if 20% is right it sounds like it is something with the engine.
Title: no start, plugs fouled within seconds
Post by: MLM on December 21, 2010, 03:38:50 PM
Another idea may be to check the temp sensor...

It may have failed in a way which registers as very cold ie cold cranking fuel is at a maximum hence the over fuel..Not even sure if its possible just an idea
Title: no start, plugs fouled within seconds
Post by: jakeb on December 21, 2010, 04:51:24 PM
I thought that too.....  I checked the sensor and it checked out via the bently.

I am going to swap in a different engine and harness.  While I am doing so I am going to check over EVERYTHING...all the wiring, fuel, grounds, etc etc.  So pretty much just start over..... The engine that is in there now didn't look very clean under the valve cover anyway and the other one I have on hand looks brand new under the valve cover...so...
Title: no start, plugs fouled within seconds
Post by: jakeb on January 02, 2011, 12:51:03 PM
it runs!!!!!!!!  Idles very smoothly, all is right with the world once again.  Happy 2011!!

I swapped in another engine, this one looked way better under the valve cover.  Also better leak down results.

When I pulled the other one out and had to swap over the crank pulley I found that the old engine had play in the crank where it would move in and out 1/4 - 1/2" so I think that other engine was just a POS.
Title: no start, plugs fouled within seconds
Post by: DesktopDave on January 02, 2011, 09:30:07 PM
Glad you found the trouble...sorry it was a whole motor.  1/2" is a lot of end play.

What kind of condition are the cam sprockets, tensioner & chain guides?  Chain case looking OK?  If you're going to trash the motor and they look OK I'll send you a few bucks so I can have a spare set.
Title: no start, plugs fouled within seconds
Post by: jakeb on January 03, 2011, 10:41:16 AM
If I decide to part it out I'll let you know.  I am going to put it on a stand and see about mocking up a SC I have laying around.
Title: no start, plugs fouled within seconds
Post by: DesktopDave on January 03, 2011, 05:10:13 PM
Ooooh. Post pics!  Are you doing something like the little Merc magnetic clutch-driven one, or something bigger?
Title: no start, plugs fouled within seconds
Post by: jakeb on January 04, 2011, 04:30:55 PM
eaton m90 i think from a ford supercoupe.  Unless I can find a rotrex for a good price.  I would really rather use a rotrex or VF so I can just have a plate cut and bolt it to the front of the engine....  still up in the air right now.  It has been a project in the works for a couple years.  I have other projects that may happen before that....such as a fiat 500 with a mid mounted FWD honda engine and tube chassis....

also sounds like i will have an m42 swap into an e21 soon...
Title: no start, plugs fouled within seconds
Post by: jakeb on January 09, 2011, 05:21:21 PM
all is good and the car is running and driving.

Here is a pic of the car the engine is in...

(http://theguestroom.net/karen02/IMG_2522%20%28Medium%29.JPG)
Title: no start, plugs fouled within seconds
Post by: DesktopDave on January 09, 2011, 06:34:04 PM
Nice roundie.  I miss those old cars.  They were never all that common, but I've only seen one out driving over the last four years or so. Makes me want to check out Craig's List for some postings.  Such an iconic car.