i have that same gas smell but its only because its cold and you drive hardOriginally Posted by a32guy
Ah, intake tubing cracks...I'll have to look into that. Also would kinda make sense as far as the problem showing up now when it's cold and things are brittle...although, I'm not sure how to relate that back to the engine temp thing. I'll inspect it this weekend.
Just to add a point for us 4 cyl guys - when the car is sitting parked in the sun, the engine bay heats up and it runs like crap until cool air flow sorts out whatever the problem is.
I just took mine to the dealer. $100 for their scam diagnostics is worth it.. I'll let you guys know what they find out
I'm taking some stuff apart this weekend to see if I can find anything out, I'll report back...
Dan
Dan
i just have this feeling that someone will find something and everyone will go AH HA! and there will be no need for this post......
well, at least i hope they do......
"Before you can think outside the box, you have to know whats in it"
-Matthew
M42 Club Member #126
Huh? I think this thread has been a great resource...surprised if anyone would say otherwise. I don't care if it's the stupidest solution ever, I just want to get it fixed.Originally Posted by Jetblack95
Dan
Dan
I was speaking with Mike Murray from Bimmer Magazine and I thik he was as stumped as the rest of us....I have tested everything including the resistance on every sensor. My car has been parked as I have to replace the brake light switch but I am taking the car in for a CA smog diagnostic on Sunday as-is...cold and with 87 octane to make sure it runs like crap! I wish I had another 2k on oil change but we'll work with what we have. I am strong on my belief that this is a catalytic convertor issue....let my no sense making ass put it this way-
If our cars were chimneys and the pedal was the fire to provide the heat...our fire would not last long as we have plenty of fuel potential but nowhere for the air to flow as needed (sorry I am involved in construction-home inspection) If the OBDI system has any flaw I think we have found it. I have yet to have a check engine light but at 208k how many miles can you expect out of the CAT? Manufacturers only warranty 50k...If the CAT is recieving irregular flows due to diagnostic issues this will overwork the whole management system and send it into a haywire mode because it compensates for raw fuel dump... I believe any mechanic will tell you if you smell any fuel bypass, whether raw or exhaust, that you have a CAT issue. We are troubleshooting everything from air intake to fuel delivery but it doesnt make sense...an efficient or new o2 should compensate for this. The purpose of the CAT is to make efficent exhaust - dont we all have a resonation issue when bogging? I sound like a V8 when cruising light to light in traffic - love it but believe this is the porblem as I usuallu experience the 'Bog' in this environment. I also have a 1500 foot climb over 2 miles in which I climb every day and this brings out the oh so best in my car. If I keep the car under 2k or over 4k I never have any problems.. . I believe the fuel return test was a failure....Lets get these CAT's replaced and see where we are then. What is a CAT to perform milage wise anyway = I would think it is tired of seeing carbon and cleaner build up from the last 14 years of use in my situation. I am a religious Cevron 89 fan as well as using Red Line Complete Fuel Traeatment and synthetic motor oil-Mobile 1. How much better can you be, I believe that the previous owner went 30k+ on the K&N filter and caused severe issues. I believe exhaust flows will take us to our solution...this is the only item that makes sense to anyone I correspond wih. Looking forward to hearing some answers this weekend. Keep me posted Please.
Mike Fowler
Mr. Mike36
well I got a call from the dealer and they said mine is a fried computer and an ignition coil. the guy said the computer smelled like burning. im not sure if this pertains to any of your own problems or not.. I'm kind of curious how this could be the issue, as it was doing the same bad idling thing both before the tire iron slid on top of the battery in the trunk and arced itself and after.. So i'm about to go $1300 in the hole for a new computer. good times
Well, this sounds like a legitimate issue for you, only because of the tire iron incident. Putting power through grounds never turns out well. Don't be surprised if that's not the only computer that got fried...though I hope for your sake it is.Originally Posted by prophecy
You may want to try shopping for a used one on here, you'll save a LOT of money...I think they regularly go for around $200.
Dan
Dan
This sounds like a very fair analysis to me. Hopefully someone will take off their cats this weekend and go for a ride long enough to get the engine warm and see if it makes a difference...Originally Posted by mr.mike36
I'm also trying to screw with the crank pos. sensor, as I see from some posts this can cause similar issues.
Someone try the cats though!!
Dan
Dan
14 inches of snow expected, and a busted VW golf in the garage. I can't try the exhaust trick this weekend
Gotcha.. expecting 12+ here. And I'm going skiing next weekend, so any fiddling is going to be pushed back until at least next Monday for me too...Originally Posted by a32guy
Dan
Dan
I got it off of the jack stands, charged the batt, and fired it up yesterday but it's snowing again and they're laying salt on the roads. So I am going to wait until it's nicer out to drive it. I was surprised that my exhaust note has not changed much at all (from a stand still at least). Maybe I should not have added the high flow resonators into the mix afterall. Seems to rev up a bit quicker but the needle is still taking too long to drop back down.Originally Posted by BMDub325is
I will touch base again after I take it for a spin. Hopefully it helps the hesitation problem.
Houston I think we have confirmation....
I just got off the phone with an experienced exhaust guy that has confirmed our problem without even looking at it. His explanation was backed by many successful installs. He said he has been converting the CAT's to an OBDII system becuse there have been numerous attempts to put an aftermarket OBDI CAT on only to fail testing. He said if its an OBDI with over 150k he guarantees the CAT is worn out as the honeycomb is really sensitive especially in the BMW's. He recently had a guy from SF bring his car in with our symptoms but he couldn't pass smog as a gross polluter. He hooked it up with an OBDII CAT and the SF smog referee said he has never seen a BMW pass with such clean emmissions - actually no detection at all. Now for those who have tested their exhaust pressure. He said a back pressure of 3-5# is about where we need to be...if there is no backpressure there could be many problems associated such as what we have described. I will touch base with my friends at M Service in walnut creek as well as Wolfgangs to see if they confirm but I am pretty sure we have a winner, has anyone had success with replacement yet? We have all talked about it, but I have another two weeks before I can shell out the money. Check around to find an aftermarket on the web because I am seeing them for under $100 bucks. Unlike the $500 plus that we are seeing from the OEM sites and stealers.
__________________
Mike Fowler
East Bay Area, CA
1992 325i
1985 318i
1996 Audi A6 Quatro
1)
2)
3) I was looking awhile ago for an aftermarket cat, but either I'm retarded or...well, yeah just retarded. Where do you find them?
Originally Posted by mr.mike36
Damn, man, I hope you're right! I want to do a OBDII cat though. Might as well take advantage of the better pipes.
Can you ask the exhaust guy how he's fitting the OBDII cats on there? If I recall correctly we need to do the headers too, since on OBDII the O2 sensor is in the header.
Let's get this done!
Dan
Dan
Also - maybe someone could take off their cats and give it a run to see if this really is the problem. I'd like to get this fixed real soon, but I don't want to go buying anything else until I know what the problem is for sure...
Dan
Dan
What's different about the OBDII cats? Do they just weld over the 2nd O2 sensor bung, or is there some way to add a second one?
Actually, IIRC, there are no O2 sensor holes in the OBDII cats, at least before the cats. There are 2 holes in the headers, and 2 after the cats if my memory serves...Originally Posted by Spood
Dan
Dan
So there are 4 O2 sensors? Madness!Originally Posted by dmurray14
Are the OBDII cats more robust or something?
Guys I agree with Mr. Mike and I also think it was my cats. I have since upgraded my exhaust manifold to obd II ( plugged up the 2 O2 sensors in the manifolds, welded the air injection ports closed) and upgraded the midsection to an obd II mid from a 1998 M3 (its stainlesd steel), plugged up the post cat O2 sensor holes, welded in a new OBD I sensor nut and installed a new O2 sensor. The OBD II cats have larger diameter downpipes, and have a true dual setup without any Y piping like the OBDI. Also from 1996 an on the exhausts are all stainless steel. I installed it today, and the car seems to have 30 more hp at the top end, and at least as much torque everywhere in the whole rpm range. I also installed all new gaskets I got from pelican parts. Finally I think my car is running like it should. Oh also, for the first time I can actually hear a roar from the rear (still stock 325ic) muffler. I definitely think exhaust airflow has improved and was the culprit in my bogging issue.
For everyone active in this thread...how many miles on your cars? I have about 161k.
So is it safe to say it solved your bogging issue then....as in it's completely gone?Originally Posted by calves2997
Also, do you think you might be able to provide a write up on the OBDII cat conversion?
Thanks a lot..
Dan
Dan
Sounds great! How is the power down low? I definately think its CATs. Looks like I know what I'll be replacing next. Thanks very much for the info!!
-Chris
ps-- 130k miles here.
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