So I finally took a much needed road trip and my car performed fine, for the most part. I even got stuck in traffic and didn't get hot with my new radiator!!!
I'm so pleased with this, and it was actually an easy upgrade.
Anyways, when I'm driving on the highway, I get a terrible smell in the cabin, but only when the windows are down; with my windows up I get no smell.
Some facts about my car:
1. 1977 AUTOMATIC - car cruises at 3000rpm at 60mph, about 4000rpm at 80mph. I don't get it past there really.
2. Its been de-smogged
3. I have a 528i ignition system installed; I also have the cam from a 528i.
4. I'm timed at about 22 BTDC at 1700 rpm. I checked centrifugal advance with an adjustable timing light and all is to spec. Vacuum advance works too, about 10-15 degrees I think. After checking all timing, I don't connect the vacuum retard because the car runs too hot when I do that. Timed 1700rpm I'm idling at about 8 BTDC degrees. (I could add a bunch of total advance and connect the vacuum retard to idle at about 8 degrees, but I'm afraid of detonation.)
5. I do notice there is a bit of oil on my engine, like especially around the pressure switch for example, and the bottom side, so I'm thinking maybe burning oil, but the smell goes away when I don't punch the gas.
Am I lean? Rich? Am I burning oil? Something with my transmission? Is it just an exhaust leak? Is my timing off? Anybody else experience this? do have a small exhaust leak near my manifolds, but the car stinks in park if I to rev 5000rpm too. I thought when I did this it was carbon build up, but after 500 miles of highway driving over the past week, its still there. It smells like burned oil or carbon- not raw fuel, and not coolant.
Any input is appreciated!!! This is driving me nuts and If I drive long enough with the windows down, I can feel the fumes on my person.
I wish I could post the smell here, but we're not technologically there yet.
terrible smell in cabin when driving on the highway?
If you have a visible oil leak (the oil pressure switch is like 20$ or less) fix it and wash the engine, that sounds to be your simplest cheapest bet to start with... Oil will drip down, and back, that's gravity and wind resistance...and can get on exhaust parts, that are hot.
Also with the 3hp22 automatic don't revit in neutral/park for extended periods of time (like emissions testing, people do lose these trannys while getting their car sniffed!) that can burn up the trans.
Also with the 3hp22 automatic don't revit in neutral/park for extended periods of time (like emissions testing, people do lose these trannys while getting their car sniffed!) that can burn up the trans.
81 528ia black - semi-dd
92 BMW K75 - dualsport/cruiser
03 Chevy Silverado 1500hd - tow-rig/bad weather
84 Toyota celica supra - drift/autox/hillclimb duty
92 BMW K75 - dualsport/cruiser
03 Chevy Silverado 1500hd - tow-rig/bad weather
84 Toyota celica supra - drift/autox/hillclimb duty
Thanks for the tip.
I think tho the revving issue was with the later 4 speed transmissions on the e28/e32 4hp-22 but I could be wrong.
I will also add its not brake fluid getting sucked into the intake, and Ive played with timing and also an AFM.
After a while I can almost feel the residue on my face.
If it is oil dripping onto my exhaust, I think I would smell it all the time, but its the time, but I really only smell it when I cruise at 70 mph or rev it to 4-5000 in park... hopefully Im wrong.
im going to get it washed. i doubt its the oil pressure switch, its about 6 months old and i checked for tightness. Hopefully ill have some good news.
I think tho the revving issue was with the later 4 speed transmissions on the e28/e32 4hp-22 but I could be wrong.
I will also add its not brake fluid getting sucked into the intake, and Ive played with timing and also an AFM.
After a while I can almost feel the residue on my face.
If it is oil dripping onto my exhaust, I think I would smell it all the time, but its the time, but I really only smell it when I cruise at 70 mph or rev it to 4-5000 in park... hopefully Im wrong.
im going to get it washed. i doubt its the oil pressure switch, its about 6 months old and i checked for tightness. Hopefully ill have some good news.
1977 530ia
Before I changed the leaky oil press. sensor, but I'd only smell the drip on the ex.pipe when I stopped. Then I found I also had an oil leak at the valve cover 
I believe I run a bit rich based on my exhaust smell but only aware when I'm out/behind the car. Maybe you are rich or burning oil and the exhaust leak lets you know at higher rpms.
Have you looked at the underside and exhaust side of the tranny for leakage?
Might there be a rat nest hiding somewhere?
I believe I run a bit rich based on my exhaust smell but only aware when I'm out/behind the car. Maybe you are rich or burning oil and the exhaust leak lets you know at higher rpms.
Have you looked at the underside and exhaust side of the tranny for leakage?
Might there be a rat nest hiding somewhere?
1981 Sapphire blue automatic
Hit 200k mi. on Fathers Day 2016!
250k October 2020
Family owned since new
Route 150 between Ojai and Santa Barbara
Hit 200k mi. on Fathers Day 2016!
250k October 2020
Family owned since new
Route 150 between Ojai and Santa Barbara
I dont think my car consumes much oil.
Maybe half-quart between oil changes? Maybe even a quart, I do seem to have a small leak because my engine bay always has a film.
I just drove 500 miles after a fresh oil change so I will see if there is any loss.
I dont get any smoke on startup, but if I rev the engine too high RPMs, Ill get a little smoke that goes away when i take my foot off the pedal. And it has that smell! Then its gone, just like that.
I dont notice the smell at idle but if Im idling for a while, maybe there is a touch of that smell. The smell dissapears if Im just rolling at high speed.
Ive set the AFM to the point where I was smelling raw fuel....
I also turned it back. Maybe im running rich but I feel like the smell is oil or carbonish... Maybe Im running lean? I try to use a gunson exhaust gas analyzer to mess with the afm. Im going to try another AFM asap.
My engine is covered in oil- my ac compressor has oil on it, and there is a film on the sway bar, also around the oil pressure sender-
I will check valve cover gasket, duck gasket, upper timing cover and pressure sensor.
I have no visible leaks on the floor, but I definitely seem to have a small leak somewhr--but there is none on my exhaust manifold..
I think you may be right about the exhaust-- Because of the smelly smoke at high RPMs, Im thinking that its something with the motor/timing/mixture rather than oil burning on the engine exterior... Does this make sense?
If you rev your e12s to 5000 rpm in neutral, do you get smoke or a smell?
Maybe half-quart between oil changes? Maybe even a quart, I do seem to have a small leak because my engine bay always has a film.
I just drove 500 miles after a fresh oil change so I will see if there is any loss.
I dont get any smoke on startup, but if I rev the engine too high RPMs, Ill get a little smoke that goes away when i take my foot off the pedal. And it has that smell! Then its gone, just like that.
I dont notice the smell at idle but if Im idling for a while, maybe there is a touch of that smell. The smell dissapears if Im just rolling at high speed.
Ive set the AFM to the point where I was smelling raw fuel....
I also turned it back. Maybe im running rich but I feel like the smell is oil or carbonish... Maybe Im running lean? I try to use a gunson exhaust gas analyzer to mess with the afm. Im going to try another AFM asap.
My engine is covered in oil- my ac compressor has oil on it, and there is a film on the sway bar, also around the oil pressure sender-
I will check valve cover gasket, duck gasket, upper timing cover and pressure sensor.
I have no visible leaks on the floor, but I definitely seem to have a small leak somewhr--but there is none on my exhaust manifold..
I think you may be right about the exhaust-- Because of the smelly smoke at high RPMs, Im thinking that its something with the motor/timing/mixture rather than oil burning on the engine exterior... Does this make sense?
If you rev your e12s to 5000 rpm in neutral, do you get smoke or a smell?
1977 530ia
I like to get things steam cleaned, especially old mercedes diesels when I would pick one up to recondition in years past. Newer gas injection cars with cracked harnesses can accelerate corrosion if they get wet. Clean is good, maybe you can get the underside cleaned.
Ron Dwyer
Milwaukee, Wi
14 Audi A8L TDI
03 530i
08 F150 4X4
Milwaukee, Wi
14 Audi A8L TDI
03 530i
08 F150 4X4
5000 rpm, I don't go there. Fraid of breaking something. And I have an issue with ignition control module(?) that nearly always causes cutting out at 4750 anyway except the occasional push in 2nd gear when engine half warm.
I have wetness underneath that is blowing out the transmission vent. Probably a failing seal, do have to top up fluid every 5k miles or so.
Have you done the O2 sensor/AFM 450 Mv calibration ala metric mechanic? How is your O2 sensor? And plugs look ok?
I have wetness underneath that is blowing out the transmission vent. Probably a failing seal, do have to top up fluid every 5k miles or so.
Have you done the O2 sensor/AFM 450 Mv calibration ala metric mechanic? How is your O2 sensor? And plugs look ok?
1981 Sapphire blue automatic
Hit 200k mi. on Fathers Day 2016!
250k October 2020
Family owned since new
Route 150 between Ojai and Santa Barbara
Hit 200k mi. on Fathers Day 2016!
250k October 2020
Family owned since new
Route 150 between Ojai and Santa Barbara
I dont hit 5000 rpm when driving, but the owners manual says to drive at 5000 for a mile or so to blow out any carbon buildup after city driving.
I dont have an O2 sensor, because I dont have lambda control...
Thinking when I replace the downpipes I will gave a bung put it for one.
I did adjust the AFM, maybe I will try messing with it some more.
Steam clean would be nice!
I dont have an O2 sensor, because I dont have lambda control...
Thinking when I replace the downpipes I will gave a bung put it for one.
I did adjust the AFM, maybe I will try messing with it some more.
Steam clean would be nice!
1977 530ia
seams like you are experiencing the same issue.. nothing to do with oil burning more like pungent gas smell, slightly raw.. windows are up it's fine on the road. I have a smoke machine to pump the exhaust system and hopefully I see leak by the manifolds... but the engine is on the rich side, which I believe is normal compared with US cars, the fumes are excessive though...
Fadi F.
1980 M535i
1997 Camry V6 5sp
2007 Tacoma 4x4
1980 M535i
1997 Camry V6 5sp
2007 Tacoma 4x4
-
PatinaBeforePolish
- Posts: 393
- Joined: Sun Jan 18, 2015 1:22 pm
- Location: Baltimore, Md.
I've had the fortune (or misfortune) to experience just about every automotive smell possible - they're all distinct.
You said no O2 sensor but are you running a catalytic converter? A too rich or lean fuel mixture could play havoc and cause the rotten egg smell.
Rear transmission seal leaking on the exhaust?
Get the engine and trans as clean as possible. Drive it hard and long enough to get everything fully warmed up and of course dry from the cleaning. Let it sit and idle in a not breezy area, up on jack stands if possible. Lift the hood and trunk, observe everything with your nose and a trouble light above and underneath the car.
You said no O2 sensor but are you running a catalytic converter? A too rich or lean fuel mixture could play havoc and cause the rotten egg smell.
Rear transmission seal leaking on the exhaust?
Get the engine and trans as clean as possible. Drive it hard and long enough to get everything fully warmed up and of course dry from the cleaning. Let it sit and idle in a not breezy area, up on jack stands if possible. Lift the hood and trunk, observe everything with your nose and a trouble light above and underneath the car.
79 528i
76 530i - Stored since 1992, can it be brought back to life?
86 944- 2023 project
78 F150- Everyone needs a truck
76 530i - Stored since 1992, can it be brought back to life?
86 944- 2023 project
78 F150- Everyone needs a truck
Thanks for the input guys!
I dont have cats, just bav manifold. I def have a pinhole leak where the exhaust guy turned the flanges to fit...
I will get it steam cleaned soon and take a look for leaks.
Transmission seal- I dont even know where to look for that! I will have to do some reading.
I did mess with the AFM again- I could swear the smell got worse on my way back from upstate ny, which is a little higher above sea level. I richened the mixture a drop on my AFM, I *think* the smell is actually slightly better.
My AFM is a reman, so I dont trust it. I will try with a different AFM soon, maybe that will be an improvement. When i first got the car, I didnt notice this stench!
I dont have cats, just bav manifold. I def have a pinhole leak where the exhaust guy turned the flanges to fit...
I will get it steam cleaned soon and take a look for leaks.
Transmission seal- I dont even know where to look for that! I will have to do some reading.
I did mess with the AFM again- I could swear the smell got worse on my way back from upstate ny, which is a little higher above sea level. I richened the mixture a drop on my AFM, I *think* the smell is actually slightly better.
My AFM is a reman, so I dont trust it. I will try with a different AFM soon, maybe that will be an improvement. When i first got the car, I didnt notice this stench!
1977 530ia
It appears that i have a small oil leak near my upper timing cover.
Not enough to drip on the floor-
Since my last oil change i did 500 miles, and it appears I burned about 3/4 quart of oil- just below the bottom line on dipstick now.
If its just the leak- great, but would that cause a smell only at highway cruising or revving the engine, from my exhaust?
Not enough to drip on the floor-
Since my last oil change i did 500 miles, and it appears I burned about 3/4 quart of oil- just below the bottom line on dipstick now.
If its just the leak- great, but would that cause a smell only at highway cruising or revving the engine, from my exhaust?
1977 530ia