BS: Emissions Test/Engine light Subaru

Subject: RE: BS: Emissions Test/Engine light Subaru
From: pdq
Date: 13 Dec 10 - 02:49 PM

Here is a site with lots of good questions and answers...

                                                    http://subarucarsfaq101.org/Subaru+Impreza/1997+Subaru+Impreza.html

Subject: RE: BS: Emissions Test/Engine light Subaru
From: Bobert
Date: 13 Dec 10 - 02:42 PM

First things first, the oil leak... If it is the rear main seal then turn the radio up 'cause it's gonna cost you a bunch to fix 'cause the engine has to come out...

"Check engine" light??? Could be anything related to the fuel injection, exhaust and/or ignition... A loose/bad spark plug wire, as John says, will make an engine miss when nit is cold or damp... If that is what it is it will improve (smooth out) after the engine warms up... It could also be a crack in the distributor cap allowing moisture inside the cap and like the bad wire or connection may smooth out when the engine is warm... Either way, it's okay to drive... If the engine doesn't die when it is cold then start it and let it warm up for 10 minutes or so...

Since the car passed emission there probably isn't anything wrong on the fuel injection side or the exhaust side... Either will give you bad readings... It doesn't hurt, however, to run a can of fuel injector cleaner thru a full tank of gas now and then...

Here's something you can do, Janie... Wait until after dark and start the engine cold, let run, open the hood and look for small flashes of spark from around the spark plug wires and ends... If you see anything like that then you have found yer problem...

B~

Subject: RE: BS: Emissions Test/Engine light Subaru
From: JohnInKansas
Date: 13 Dec 10 - 01:55 PM

I'm not familiar with the car model in question, but many cars are more sensitive than one might expect to even slight tilt in the surface where they're parked when reading the oil level. You might give some thought to whether your erratic readings were all taken in the same, or very similar, "vertical orientations" of the vehicle.

Different ones also vary in how quickly the oil runs down after the engine is shut down, and a rather large fraction of the oil in the engine can be retained higher up in the engine, especially if the engine wasn't "fully hot" when parked.

Some dipstick tubes also retain oil, so it's necessary to always pull the dipstick, wipe it fully clean, and then reinsert fully and pull out immediately before reading the level. Oil retained in the guide tube can make it appear to wet the dipstick well above the actual level of oil in the pan, so you need to look for a "well defined line" where the oil on the dipstick ends to assure an accurate reading. "Wiping the dipstick" means wiping until it "looks dry" in the area where you'll look for the oil level indication, and it should still look dry when you pull it out to read it at all of the area immediately above the oil line.

With a few engines, cleaning the dipstick and then running it down to swab the oil out of the tube, then cleaning again, before running the stick down for the measurement may be necessary. This is especially likely to be needed if there's significant "gunk" in the engine, since the sludge (sticky oil) can accumulate anywhere that the oil doesn't flow through, as in the dispstick tube.

An intermittent engine light is, as mentioned before, frequently caused by "electrical noise" in the system. Most commonly the noise comes from a poorly seated ignition (spark plug) wire, although a loose connection almost anywhere can be the culprit. Deteriorated high voltage wires can also be the cause due to "corona emissions," but even on a "used engine" I'd expect a competent shop usually to put new ignition harness on.

Some emission test methods do require that a "plug wire" or "coil wire" be disconnected so that a connection can be made to the test machine, and the technician may not have re-seated the wire securely. "Modern" machines usually use an inductive pickup that just clips around a wire, but it's still possible to dislodge the one it's clipped to. "Modern engines" usually have a terminal on the "distributor" that test equipment can hook to, but a careless technician can disturb other wires getting to the connection.

The "coil wire" between the spark generator and the distributor or the "number 1 cyclinder" plug wire would be the main suspects.

If the source of an electrical noise isn't in the ignition system "hot side" it most often is at one of the main ground points, where the circuits are connected to the engine block or body frame.

Random bad connections can be almost impossible to find "electrically," so the usual procedure is to "inspect visually," and "wiggle aggressively" until something is found dirty or comes loose. The visual check often means disconnecting, wiping or scraping, and reconnecting securely, and of course you need to be prepared to repair anything that "comes loose" when you wiggle it.

John

Subject: RE: BS: Emissions Test/Engine light Subaru
From: kendall
Date: 13 Dec 10 - 12:43 PM

Janie, it is quite possible that all you have is a loose spark plug wire. It will make the engine miss and it will activate the check engine light.
The oil leak, sounds to me like when it reads low maybe you didn't push the dipstick all the way in, and when it reads full that you did push it in.
I have had good luck with BARS LEAK for a leaking rear main seal. It's very common in antique cars.Much cheaper than having the seal replaced.
Whoever told you that it cant be stopped should take up knitting.

Subject: RE: BS: Emissions Test/Engine light Subaru
From: The Fooles Troupe
Date: 12 Dec 10 - 11:11 PM

"the oil level as indicated on the dip stick fluctuates somewhat erratically. I have had the experience, more than once, of checking the oil and the reading indicating I am more than 1 quart low. Add a quart, and then check it again, and the oil level is over the full line"

Had some experience with this - it can mean that the engine has a lot of gunk in it (you had a second hand, not rebuilt!) so that the oil does not always flow back properly to the sump/oil pump - which may not help keep oil pressure up, and may lead to excessive wear and serious damage. The oil heats, and expands, as does the passages, so the oil flow can be slower than normal, when adding, or checking, but will usually flow down eventually.

When this symptom appears, I did an 'engine flush', which means you put a special detergent additive in for a short while before the oil change, helps 'flush out the gunk'.

I did run a car for ages with a minor oil leak, cause the clowns damaged the oil sump plug sealing washer... eventually insisted that it be replaced, and the leaks stopped...

This was with cars that were 'simple mechanical' - no 'car computer', so can't help with that side ... repairs there can be expensive and nasty ... it seems that older 'newer cars' are less tolerant of 'aging gracefully'.



I'm not a mechanic, btw...

Subject: BS: Emissions Test/Engine light Subaru
From: Janie
Date: 12 Dec 10 - 10:51 PM

Grasping at straws as nothing turned up helpful searching Google. Two issues. Oil leak and Check Engine light. Hoping there are people among us who know more than a little about car engines.

History, then recent chain of recent events.

History:

Last Christmas I blew the engine in my 1997 Subaru Legacy Outback. Put in a used engine. Not rebuilt, used. All belts, valve cover gasket, rear main seal, etc, were replaced at that time. The replacement engine leaked oil from the oil pan. Very minor oil loss. Took it to my main mechanic, then back to the guy in West Virginia (where I was when the old engine blew) on my mechanic's advice, since it had a 6 month warranty.    Was told by the guy who installed the used engine the leak was essentially unfixable and to just be sure I checked my oil weekly. (I am just now figuring out I may have got snookered on that one.)   The guy said this model Suby didn't have a replaceable oil pan gasket.    I have religiously checked the oil. It is hard to read the dip stick. I am assuming it is my failure and difficulty reading the dip stick, but it seems like the oil level as indicated on the dip stick fluctuates somewhat irratically. I have had the experience, more than once, of checking the oil and the reading indicating I am more than 1 quart low. Add a quart, and then check it again, and the oil level is over the full line. Or I might check it one morning and it is halfway between the full and fill lines, check it the next morning, and it is at the full line. I usually check the oil in the morning after the car has been sitting all night.   I am pretty sure that more than once I over-filled the oil. Now I'm leaking oil from the rear main seal and the valve cover gasket. Leaks are still minor in terms of loss of oil.

Immediate problem and recent chain of events:

Friday I had the car inspected. It passed the emissions test with no problem. It is hard to find information about the North Carolina emissions test, but they apparently hook a computer up to the engine to check the emissions control system, i.e. they do not stick something in the tailpipe to read the exhaust emissions. Drove some but not much after that. Less than 40 miles Friday evening and Saturday. Went out late this afternoon. Weather has been cold and wet since last night. It sounded rough and weak when I started it. Drove one block. There was a definite miss and the engine light came on and started flashing. Also what sounded like a belt squeal. Stopped immediately. It smoothed out just a bit, so I limped the block back home to the driveway - engine light intermittently flashed and stayed solid.

Turned it off, popped the hood and restarted it a few times. The squeal had disappeared.    At first it was still missing badly.    Came inside and started googling. Flashing check engine light=stop driving immediately.   Solid check engine light, you can drive it, but get it checked out sooner rather than later. Went back out and started it again. Miss was gone, seemed to have full power and to be running smoothly. Check Engine light is on and solid.

My mechanic is about 12 miles from here. In the morning, f it starts and runs without noticeable miss and the check engine light is solid, I will drive it there rather than have it towed.

I'm wondering (hoping) if it is possible the inspection guys didn't connect something back solidly after they did the emissions inspection, that whatever they plugged back in perhaps rattled loose and is the source of the problem?

I am assuming the oil leaks will not do further damage to the engine as long as I don't allow the oil to get too low. They are going to be an expensive fix and if I can hold off for 2-3 months I'd like to do so.

Hope this post isn't too incoherent. I live 40 miles from where I work and both are rural locations. Haven't sussed out a mechanic in the little town where I work now. Don't have a mechanic in the little town to which I moved. The mechanic I have been going to for about 10 years in the little town where I did live is honest but not inspired. He has done no work on the Subaru, which I bought soon after I moved, and I have only been to quick oil change places since I moved, except for the engine replacement that occurred 300 miles from home.