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DISCUSSION => Engine + Driveline => Topic started by: asubimmer on March 19, 2007, 10:24:50 AM

Title: Engine Probs...
Post by: asubimmer on March 19, 2007, 10:24:50 AM
Well this past week was my spring break and I went to the beach. Before I left I took off the full exhaust and front sway bar. I was test fitting the turbo manifold. I left the car in the air while I was at the beach. I left the turbo manifold on but I capped it off so nothing would get in my engine while I was gone. BTW the car was parked inside a garage the whole time.
 
Well I get back from the beach and put the exhaust and sway back on. I also rewired the reverse lights since the guibo took the wires out. I went to start it up and it fired right up but it sounds like a wrx when you hit the gas now....
 
The check engine light isn't on or anything. The car feels fine below 5k. Above that it feels like I'm missing some power. I'm guessing that it may be one of the gaskets is missaligned? But that still doesn't explain why the top end feels weak. I'm pretty sure its running rich too, its deff eating a lot more gas. I pulled the plugs and they are fine. I do think my o2 is on the way out but would it make a differance like this?
 
I'm just confused as to what it is since the car was fine when I pulled it into the garage. Is the car just mad that I didn't take it to the beach too?? :rolleyes:
Title: Engine Probs...
Post by: badboypolar on March 19, 2007, 11:07:39 AM
Sounds like the O2 is either bad, damaged or unpluged.
Title: Engine Probs...
Post by: bmwman91 on March 19, 2007, 11:10:27 AM
It may very well be mad, who knows.

If it is louder than before, maybe you forgot to put the gasket in after the header?  Check the cat-back flange too.  Sounds pretty odd.
Title: Engine Probs...
Post by: e9nine on March 19, 2007, 11:13:51 AM
Did you unscrew the O2 sensor at the port of directly off the downpipe?

The gaskets for the exhaust drop off easier and can go unnoticed. It sounds more like a case of either, a gasket, you didn't connect the exhaust back the right way and it's loose or you have sprung a leak/cracked something along the exhaust flow path.
Title: Engine Probs...
Post by: asubimmer on March 19, 2007, 01:31:53 PM
yeah I did remove the o2 sensor when I took of the exaust.  I only unscrewed the exhaust at the head and the bottom of the manifold.  I took the whole back off in one peice.  So I guess that leaves me with the exhaust manifold's top and bottom gaskets.  Everything should be tight but I should double check.  
 
So would a bad o2 kill the top end power?  I can get up to 7k but it seems slower to get there and it deff doesn't feel as strong up there as it did before.  
 
I do know for sure that all the gaskets are on there.  I made sure that they didn't fall off when I was putting everything back together.
Title: Engine Probs...
Post by: Tonyb on March 19, 2007, 10:03:50 PM
I had the same problem with a bad o2, but it was'nt any louder. Maybe you have a leak and a bad o2? By the the way happy B-day you old fart! (your only 3 years older than my son!) With a bad o2 the computer can't tell how rich or lean the motor is running, so you get poor mileage and performance.
Title: Engine Probs...
Post by: asubimmer on March 19, 2007, 10:14:19 PM
lol thanks, for some reason 20 seems really really different.  I have an AEM wideband that I am going to install after I figure out what the pins on the DME are so I can wire the MS into the factory harness.  :)
Title: Engine Probs...
Post by: Tonyb on March 20, 2007, 01:44:04 AM
That won't help your o2 problem. If it's ready to go then it won't be a waste, since you need one, will it?
Title: Engine Probs...
Post by: maxwellredrum on March 31, 2007, 10:25:21 AM
mine was having the same problem, everyone was like wtf did you do sounds like a subaru! turns out one of the ground wires to my coil pack had let go and only made contact intermittently....just food for thought.
-Max
Title: Engine Probs...
Post by: 318is91 on April 03, 2007, 05:30:41 AM
have a friend hold a balled up rag over the exhaust outlet and look for leaks if you have a leak before the o2 sensor it could be either drawing in fresh air or letting exhaust out either way it could mess up the o2 reading and there for fuel and this could be exaggerated at high rpms. ie a higher percentage of exhaust is forced out the leak because theres more pressure, so the 02 sensor isn't affected by the lost fumes, the car sees too little exhaust, it thinks it isn't burning enough fuel for that rpm ie it thinks it is running lean and dumps in fuel too compensate.

so all that too say yes it could be just a exhaust leak before the 02 sensor

hope that helps

ps also a bad 02 sensor could do the same thing... and they all work essentially the same so you can use a o2 sensor from practically any car so equipped
Title: Engine Probs...
Post by: asubimmer on April 03, 2007, 09:24:04 AM
hey guys I called AEM yesterday and there is a little turn knob on the back if the gauge.  Its really small and I never even noticed it before they told me.  But you can turn it to make the gauge send a narrowband signal instead of a wideband one.  So I am going to try and put it on if I have time today.  So I am pretty sure I need to send the signal from the gauge to the pin #70 on the ecu?  And I can take power and ground from the o2.
Title: Engine Probs...
Post by: asubimmer on April 03, 2007, 10:01:55 PM
well I got the AEM wired up and working and the car is still pissed.  The old o2 was deff toast but the car isn't idling good at all and it sounds like a wrx.  I haven't had a chance to get on it but the car's AFR's seems to be fine.  At idle the car bounces from like 400-1000rpms but it doesn't cut out.  The vacuum lines are fine.  I'm kinda confused as to what the prob could be.  I'm hoping that I haven't lost a valve or something...

If anyone has any idea's I would really appreciate it as I have to drive 2 hrs  home fri :(
Title: Engine Probs...
Post by: nickmpower on April 03, 2007, 10:26:32 PM
Is this the AEM UGO?
Title: Engine Probs...
Post by: asubimmer on April 03, 2007, 11:05:11 PM
UEGO yup, there is a rotating switch in the back that I moved from the wideband signal p0 to the narrowband signal p4.
Title: Engine Probs...
Post by: nickmpower on April 03, 2007, 11:21:35 PM
hmmm. I didnt know it could do that. Nice
Title: Engine Probs...
Post by: asubimmer on April 04, 2007, 12:23:36 AM
so someone said it sounds like I may have lost a piston ring....?  what simptoms are we lookin at for that?
 
thing is I pulled the car into the garage and it was fine.  It sat for like 4-5 days and then when I put everything back together and fired it up it sounded like crap.
Title: Engine Probs...
Post by: nickmpower on April 04, 2007, 12:33:59 AM
check the exhaust gaskets again. Is it louder in the engine bay?
Title: Engine Probs...
Post by: bmwman91 on April 04, 2007, 01:08:24 AM
A dead piston ring would leave LOTS of blue smoke coming form the tail pipe.  Did you somehow crack a weld on the header at one of the collector points?
Title: Engine Probs...
Post by: asubimmer on April 04, 2007, 07:32:51 AM
Quote from: bmwman91;22872
A dead piston ring would leave LOTS of blue smoke coming form the tail pipe. Did you somehow crack a weld on the header at one of the collector points?
nope the header is fine. what else would leave me feeling low on power? The car isn't smoking, but the idle is really messed up even more than when my vaccum lines went out. What abour a bent valve or something? I am tryin to plan for the worst and hope for the best...
 
I would make a vid of it but my camera doesn't do sound :(
 
btw I am getting HORRIBLE gas mileage, like 15ish on the highway!  and barely enough power to get up the mtn.
Title: Engine Probs...
Post by: dude8383 on April 04, 2007, 02:45:24 PM
when is the last time plugs and wires were changed?

If you've already got the COP conversion...the dis-regard that.

My car used to run like shit until I realized that the plugs were FINISHED!
Title: Engine Probs...
Post by: asubimmer on April 04, 2007, 03:37:15 PM
I do have the COP conversion.  The plugs had carbon buildup on them from running rich when the o2 was dying.  I put in new plugs a few minutes ago and its acting the same.  One really weird thing is that the coil closest to the firewall is like melting some crap out of it?  Its really weird, I'll take a pic of it later tonight.  And that spark plug looked fine and didn't have carbon build up.
Title: Engine Probs...
Post by: badboypolar on April 04, 2007, 04:35:12 PM
If a coil pack is "melting" or oozing, replace it immediately. It means that is it over heating internally and it will go bad very soon and in some cases catch fire. Most do not catch fire, however since you are using it in a non-intended way it may not have the over-heat protection and may catch fire. It could aslo be causing your engine problem.

Please please please do not take this warning lightly. I've seen it first hand and do not want your next thread to be "my car caught fire".
Title: Engine Probs...
Post by: asubimmer on April 04, 2007, 05:26:43 PM
ready for the weird?  That is the 2nd coil to melt like that....
 
both were in the same spot, the one closest to the firewall.  This coil has only been in for about a week and its already starting too.  Any reason why one would do this?  Much less two that fast?  
 
I am considering selling all my turbo stuff and goin x50/52 soooo heeeelp!!!  I love the m42 but I am just getting frustrated w/ it.
Title: Engine Probs...
Post by: badboypolar on April 04, 2007, 06:19:14 PM
I don't know why you would be losing coil pack so often. I'd look at heat in that area (from header or trans or being directed that way) or a bare wire.
Title: Engine Probs...
Post by: 318is91 on April 05, 2007, 08:52:07 AM
sounds like something might be shorting out... or that it is getting commanded on all the time and overheating? maybe its not grounding through the right path. It could possibly even be caused by the plug? did you change the plug as well when you swapped the pack the second time? and just double check your wiring too that coil pack maybe something is a little funky...
Title: Engine Probs...
Post by: Choking Hazard on April 05, 2007, 09:20:53 PM
Seems like it could be related all right....