Exhaust Smoke

Forum for discussing engines in general, anything engine and not tuning-specific belongs here, such as power adder discussions (turbos, blowers, nitrous, meth / water injection, exhaust setups, etc...)

Exhaust Smoke

Unread postby gamh44 » Mon May 11, 2020 12:23 am

I know this is a tuning forum but the brains trust here is better than most so ...
I'm trying to trace the cause of smoke/vapor coming from the exhaust.  There is no X or H pipe and it is only coming from bank 2.  I first noticed it after a bunch of stuff went pear shaped last year.  It is probably all related but I just want to track down what could be actually causing the smoke.  I first noticed it when I got the car running again and it is now quite the smoke machine.  Certainly beyond driveable.

The smoke is fairly white although some have suggested a tinge of blue.  Doesn't really smell much like oil smoke either.  Smoke doesn't start immediately on a cold start but after a minute or so and gets pretty bad soon after - well before full temp. Seems to have gotten worse each start.

Here is my list of possibilities

oil smoke - via worn rings or valve stem seals
coolant vapor - via broken intake manifold gasket, blown head gasket or cracked head/block.

I initially though it may have been raw fuel but I am not sure it would create such a plume of visible smoke or vapor.

Anything else I should be chasing?
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby decipha » Mon May 11, 2020 1:55 pm

I figure with straight pipes theres no cats right?

I'm assuming your not running e85 which emits vapor out the exhaust.

how much oil are you loosing between oil changes?

rings can be verified with a compression test. toss a cap of oil in there and see how much it comes up.

valve stems will usually puff smoke on first startup when cold and then go away.

how much coolant are you loosing? any overheating issues? a cap pressure tester will let you know if you have seepage if it doesnt hold pressure when u pump it up.

if you have any race gaskets those need to be replaced every year.

raw fuel is usually black smoke. if you believe it could be fuel check the regulator first and make sure its not leaking. Hit each primary with a temp gun and see what they read at warm idle when its puffing.

make sure the o2s are switching and that you dont have any major fuel errors.

what do the plugs look like?

what all changed from last year with no smoke to now?
User avatar
decipha
Tooner
 
Posts: 19690
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Decipha Ponto
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce
07 GMC 2500HD 6L - Veranafer
06 Chrysler 300 AWD - Sharifa

Re: Exhaust Smoke

Unread postby wwhite » Mon May 11, 2020 2:19 pm

In the past, I have experienced three(3) hard to track down smoking issues:

First, master cylinder, leaking brake fluid into power brake booster;
- vacuum from engine, sucks brake fluid in from booster
- causes white smoke, don't recall smell
- smokes worse when you press brakes
- brake fluid always going down

Second, vacuum assisted power steering pump valve;
- vacuum from engine, sucks power steering fluid through worn valve
- causes white smoke, not much, still drivable
- power steering fluid always goes down
- engine v8 early 90s

Third, smog air injection system, that has air injection on heads;
- doesn't smoke when cold
- doesn't smoke when accelerating
- James Bond type smoke screen when decelerating, high rpm
- cause from loose air injector on head, when decelerating, engine has high vacuum, sucks oil from top of head.
- engine was a 4 cylinder late 80s

So, as Decipha said above, should be easy doing compression test to rule out rings.

If your engine has 'air injection smog' type stuff, one bank, maybe something there.

What type of engine is having this problem?
wwhite
General Poster
 
Posts: 51
Joined: Fri Feb 01, 2019 5:15 pm
Location: Victoria, British Columbia
Name: Warren
Vehicle Information: 1994 Ford F150, SD KID1, TunerPro-RT, QH
351w, long tubes, eddy 3881, XE258HR-12
Vehicle 2 Information: 1964 M100 460, short box
Vehicle 3 Information: 1964 Meteor 390, 2dr, breezeway
Additional Vehicles: 1978 Alfa GTV spica
1978 Alfa spider

Re: Exhaust Smoke

Unread postby gamh44 » Mon May 11, 2020 11:51 pm

Gents

Thanks for the detailed responses. I am clutching at straws at this stage. I’ll add some detail and then go into how this all started in the next post. It may be hinting towards something.

Engine is 5.0 HO with TFS1 cam and TW170 heads, MassFlo (Pro-M) EFI. Bottom end is stock.

Exhaust has cats. Smoke is appearing way before these are up to full temp. Not sure if that makes a difference.

Running 95 or 98.

Have done a compression test and all cylinders come in around 175PSI. Didn’t try adding a squirt of oil since they were all within about 10PSI.

Not valve stems by the sound of it – smoke is nothing on startup and gets going after a minute or so.

Car has only driven out of the garage and back since this started so no idea about oil or coolant consumption (nil at this stage). It just can’t be driven like this – very James Bond like.

Just replaced the FelPro 1250s – needed to ditch them anyway. No change to smoke/vapor.

Smoke definitely not black so doesn’t sound like raw fuel.

I don’t have a coolant pressure tester but might make something up to check this. The colour of the vapor looks more like coolant than anything else.

Prior to all this, HEGOs were switching fine and FE% was less than 2-3% across the board.

I’ve pulled the plugs a few times and they usually look a little rich (black) to me. Although most recently (after a couple of very short starts – around a minute or so each) the middle plugs 2,3,6,7 were a little white (lean). Not sure if this indicates anything given the really short runs.

No power steer and no smog.

Brake vacuum sucking fluid is a doozy! The vac on this engine goes into the intake up top and would likely cause smoke on both sides I would think.

I’ll post back with the story of how this all started.
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby gamh44 » Mon May 11, 2020 11:56 pm

I’ll try to be brief with this. This is what happened from no smoke to smoke.

Had the car running well with a stock A9L tune along with basic changes to MAF Transfer, Injector details etc. Still had plenty to do but it was pretty good.

Decided to port all that over to A9L2 before going any further – obvious advantages with simplified spark and mechanical idle and everything else.

Loaded up the adjusted A9L2 tune. I tried to start the car a few times. The first couple were no go. I tried WOT to see if it was too rich and it fired three times but wouldn’t keep going. Loads of fuel smell so I stopped and swapped back to the previous A9L tune. Started it up and ran for a couple of minutes to clear out the fuel. I never really considered at the time that this may have contributed to what happened at the next startup where everything went belly up.

It would have been a week or more later starting back on the old (previously fine) tune and something happened as soon as I hit the starter. The starter motor stopped and the engine didn’t start. I assumed I just didn’t hit the starter button hard enough. Then the fuel pump kept running. I tried a few different tunes, replaced the QH battery and no joy. Still fuel pump running. I made no attempt to start at this stage. Fuel pump is wired properly through the ECU so normally runs for a short time only on ignition.

Eventually traced a couple of electrical issues where ECU had no power. Fixed these, hit the key and the fuel pump ran and stopped as normal. Hit the starter and away we go. All seemed to be back to normal. Except it was now producing a small amount of smoke/vapor out of the bank 2 exhaust. Bank 1 was clear.

Packed it away and came back a week or two later and same deal. Maybe worse.

Checked compression – all good but still smoking.

Swapped out FelPro 1250s – still smoking. Seemed like it was getting worse.

It has only been up to full temp once since all this started – just before the compression test.

And that’s where we are … and I have no idea, except to suggest that there is probably some coincidences occurring.
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby decipha » Tue May 12, 2020 4:25 am

if it loaded up with fuel then the cats are prob working over time to get unsaturated

run it and drive it.

once I found someone hooked up the windshield washer reservoir hose to a vac line. It was spitting out some vapors til I figured out what was up.
User avatar
decipha
Tooner
 
Posts: 19690
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Decipha Ponto
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce
07 GMC 2500HD 6L - Veranafer
06 Chrysler 300 AWD - Sharifa

Re: Exhaust Smoke

Unread postby wwhite » Tue May 12, 2020 2:35 pm

hooked up the windshield washer reservoir hose to a vac line

Thats a good one.

How is the breather/vent/PCV on the valve cover for bank 2?
wwhite
General Poster
 
Posts: 51
Joined: Fri Feb 01, 2019 5:15 pm
Location: Victoria, British Columbia
Name: Warren
Vehicle Information: 1994 Ford F150, SD KID1, TunerPro-RT, QH
351w, long tubes, eddy 3881, XE258HR-12
Vehicle 2 Information: 1964 M100 460, short box
Vehicle 3 Information: 1964 Meteor 390, 2dr, breezeway
Additional Vehicles: 1978 Alfa GTV spica
1978 Alfa spider

Re: Exhaust Smoke

Unread postby gamh44 » Tue May 12, 2020 2:59 pm

Windshield vacuum cleaner. Every car should have one.

PCV still rattles nicely so it would seem to be OK.

Cat could well have been loaded up with fuel. I'll look at smoking up the neighborhood as soon as I get a chance!

Thanks again for helping out.
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby gamh44 » Sun Jun 28, 2020 1:38 am

So I decided to yank the engine and fix a couple of exhaust leaks.  While it was out I replaced the FEL1250 gaskets with some long term units.  I also decided to mic up the bores and pistons since most everything was apart.  It could probably do with a bore but I reckon I might leave that for another day.

Dropped it all back in and now I am having some troubles getting it running.  It is slow to fire then coughs and splutters a bit and will only keep going above around 2000rpm and it is like it is running on well less than all eight.  I am using the same tune that drove it into the garage to pull the engine, which certainly wasn't doing anything like this.

My immediate thought was that the distributor was out 180*.  I have checked and checked and checked again.  I removed the valve cover to watch the #1 intake valve close as the mark on the damper comes up to TDC.  I used the thumb on the spark plug hole technique to check for compression.  I also used a small rod in the spark plug hole to estimate where TDC was in case the damper had slipped.  Initial timing is at 10*.

What have I missed here?  I want to spin the distributor 180* just to prove it's not that but it just doesn't make sense.  And I don't want to do any damage.  Does an engine actually run with the dizzy out by 180*?
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby decipha » Sun Jun 28, 2020 7:48 am

no if its out 180 you'd know with back fires in the exhaust

if it was running before and not now then double check your work
User avatar
decipha
Tooner
 
Posts: 19690
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Decipha Ponto
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce
07 GMC 2500HD 6L - Veranafer
06 Chrysler 300 AWD - Sharifa

Re: Exhaust Smoke

Unread postby gamh44 » Sat Jul 04, 2020 1:14 am

This thing has got me over a barrel.  It is still firing, with some difficulty getting going, and only really running over 2000RPM.  Even then it sounds like it is running on three cylinders.  I am sure there is something simple that I have missed.

I have double and triple (and more) checked everything on the outside of the engine.  I don't want to go opening it up again for no good reason.  I didn't do that much inside anyway.  Unless I left a rag shoved in one of the ports?!?!

I am definitely getting some backfire through the exhaust.  Despite my better judgement, I spun the dizzy 180* and not surprisingly, it didn't fire at all.  I just wanted to prove a point to myself.

A timing light shows a spark on all cylinders (on the starter only).  This is sometimes inconsistent though, missing a fire before going back to normal.  Could this just be not enough juice to the coil - given the alternator is not running at any decent RPM.  I'm not sure of whether checking timing on the starter is good practice.

A log of the start seems to show that all the sensors are sending signals.  I also checked the connections between the TFI plug and the 60 pin ECU plug and they are all good.  I checked a bunch, but not all of the connections that go through the two 10 pin salt and pepper plugs.  

Different tunes that previously worked fine yield the same result.

How far out would timing need to be to create such a poorly timed engine?

Is it worth checking TDC more accurately (e.g. using a piston stop in the spark plug) just to make sure the balancer hasn't slipped?  Just roughly it would have to be within 5 degrees.

Could a broken/disconnected electrical connection create such havoc?

I haven't really looked at fuel delivery except to check all the connections.  Could mistimed fuel cause the popping and rough running?

Is there anything I can log to help me diagnose what might be happening?

Any thoughts appreciated!
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby decipha » Sat Jul 04, 2020 8:11 am

nope its purely mechanical your on your own

verify firing order first then tdc next.
User avatar
decipha
Tooner
 
Posts: 19690
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Decipha Ponto
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce
07 GMC 2500HD 6L - Veranafer
06 Chrysler 300 AWD - Sharifa

Re: Exhaust Smoke

Unread postby gamh44 » Sat Jul 04, 2020 8:29 pm

decipha wrote:nope its purely mechanical


Thanks, that narrows it down a lot!
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby decipha » Sat Jul 04, 2020 9:50 pm

you stopped reading too soon

decipha wrote:verify firing order first then tdc next.
User avatar
decipha
Tooner
 
Posts: 19690
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Decipha Ponto
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce
07 GMC 2500HD 6L - Veranafer
06 Chrysler 300 AWD - Sharifa

Re: Exhaust Smoke

Unread postby gamh44 » Sun Jul 05, 2020 8:28 pm

Apologies. Wasn't being sarcastic, if it came across that way.

As per the post above, I've been chasing all manner of possibilities. If it is purely mechanical, there's a lot less to check!

I have confirmed TDC with a piston stop and a dial indicator. Both methods have the marks on the balancer spot on. Firing order also checked and confirmed.

I have also checked that the TDC where the rotor is hitting #1 is the compression stroke. I have used the thumb in plug technique as well as following the valve events and checking both are closed.
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby decipha » Sun Jul 05, 2020 9:58 pm

nah no sarcasm inferred

if all is well then a faulty pickup or weak coil would be the next likely culprit other than the cam being a tooth off or the like
User avatar
decipha
Tooner
 
Posts: 19690
Joined: Mon Jul 15, 2013 5:29 pm
Location: New Orleans, LA
Name: Michael Decipha Ponto
Vehicle Information: Supercoupin' x10
90 (4x 5spds) - Dante, Ruby, Daja, Ava
91 4r70w - Skarlett
92 (2x) 5spd & auto - Bianqa, Andrea
93 auto - Danika
94 5spd Rionda
95 auto Aisha
Vehicle 2 Information: Others:
00 Lincoln LS - Luanda
98 Camaro SS - Bounquisha
02 Harley F-150 - Sasasha
03 Marauder - DyShyKy
00 Explorer 5L - Bernyce
07 GMC 2500HD 6L - Veranafer
06 Chrysler 300 AWD - Sharifa

Re: Exhaust Smoke

Unread postby gamh44 » Mon Jul 06, 2020 1:25 am

Yeah, I might throw another coil at it and see how it goes.

I have been wondering about the cam slipping a tooth. My next step was to degree the cam to see how the timing looks. If I do this with the hydraulic lifters in place, I can see that it might affect the lift (if the lifers bleed down) but it should give a pretty good indication of timing shouldn't it? Just trying to save taking the top off again.
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.

Re: Exhaust Smoke

Unread postby gamh44 » Sat Jul 18, 2020 2:27 pm

Looks like it was either coil or plugs. Replaced both and it fired right up.

I did make an attempt to degree the cam, with the hydraulic lifters in place. Not surprisingly, the opening and closing were impossible to get a consistent value for. BUT, the timing for max lift, both intake and exhaust came out within half a degree. Just had to be sure not to rush. Not much good for checking an unknown cam but gave me confidence that mine was still in the right place.

Back to the exhaust smoke, that lasted about 20 minutes at full temp. When it was all apart, I gave the cat a wash and the smoke was minimal on startup and a lot less than before as it got hotter and then faded away completely. I'll see if it is totally gone once I start it up again ....
gamh44
Power Poster
 
Posts: 144
Joined: Mon Apr 30, 2018 7:54 pm
Name: Geof
Vehicle Information: Cobra replica. 302 HO from Mustang. 8LD ECU with chip. Massflo (Pro-M) EFI. Trickflow heads and cam. QH Jaybird and F3v2 chip. TunerPro RT.


Return to Speed Shop & Engine Talk

Who is online

Users browsing this forum: No registered users and 1 guest

cron