Trying to re-seat injectors

[Phibs]

Let me add the way I know there is gas in oil is the level on dipstick is waaaaay past full after an oil change yesterday. Compression test says cyls are fine as well.

[drwrx]

I have mad fuel in oil after yesterday when andrew put in the 740s and changed my oil.

Were you able to measure it? Did it add another quart to the oil?
I'm convinced the smell is not enough to go by especially at this time of year.

There will always be a little bit of gas and some gas smell in your oil (no such thing as complete combustion) but an extra quart over just a week or so is bad juju. What's your milage been like?

[Phibs]

I have mad fuel in oil after yesterday when andrew put in the 740s and changed my oil.

Were you able to measure it? Did it add another quart to the oil?
I'm convinced the smell is not enough to go by especially at this time of year.

There will always be a little bit of gas and some gas smell in your oil (no such thing as complete combustion) but an extra quart over just a week or so is bad juju. What's your milage been like?

I am not able to measure it but it looks like a quart on the dipstick, yes. And this is after LESS THAN 24 hours. Looks like ~200 mi/tank with light driving.

[BryanH]

Is it LOTS of short trips...like over 15 miles?

Or are you letting the car get warmed up?

I have to wonder if the car is getting out of its cold start cycle.

[Phibs]

Is it LOTS of short trips...like over 15 miles?

Or are you letting the car get warmed up?

I have to wonder if the car is getting out of its cold start cycle.

This is after the trip back from AT ( ~ 20 miles ), and one trip to work in the morning ( 5 miles ). But this did not happen before my fuel pump & injectors, and my drive has not changed at all.

[Sabre]

Your drive hasn't changed, but your car has... significantly. Those injectors are flowing a lot more fuel.

Do you warm your car up in the morning, or do you just turn it on and start driving away in 30 seconds?

Your trip is SO short that you could very well be dumping a LOT of gas during that cold start period as Bryan pointed out. If you are driving while under cold start, this would explain a lot. I warm up my car 2-5 minutes normally, but that is unusually long since I have a built motor. For you, I would say 2-3 minutes, or until the idle drops to 1000rpm or less.

[Phibs]

Your drive hasn't changed, but your car has... significantly. Those injectors are flowing a lot more fuel.

Do you warm your car up in the morning, or do you just turn it on and start driving away in 30 seconds?

Your trip is SO short that you could very well be dumping a LOT of gas during that cold start period as Bryan pointed out. If you are driving while under cold start, this would explain a lot. I warm up my car 2-5 minutes normally, but that is unusually long since I have a built motor. For you, I would say 2-3 minutes, or until the idle drops to 1000rpm or less.

Why would I be dumping any gas ever? 550cc to 740cc, dumped no gas before, dump a lot of gas now.... explain engineer!

[Phibs]

Adding one more data point:

The car feels better and accelerates faster on partial throttle. I don't get any more gain on full throttle, in fact it seems slower as well. Tip-In table adjustments?

[Sabre]

During start up (this is especially so during cold days) the engine is throwing LOT's of fuel at idle till the car starts up. This is to help it idle smoothly and warm up quickly (I can show you just how much fuel sometime by showing you the maps in my Hydra). Think of it like a choke in old cars. The time that the dumping fuel to warm up varies according to how fast your car heats up. In the summer, the car doesn't need to do this very long, so a 30 second warmup time (aka, the time that During this time, the ECU is taking the amount of fuel that it needs to idle(X) and richening it up by a percentage (Y). So you have throttle position (essentially) x Y =Fuel amount flowed (Z). If you are not allowing your car to warm up more during the winter, this time increases that it multiplies your throttle input's by. In this case, you could very well be going to work while it is still doing it's nice little mulitplying. It is a decaying function, so as time goes on, the multiplier goes down.

Put simply(these numbers are made up since I don't know the scaling factor, but the results are the same)

Code: Select all

Time             0-60   60-120  120-180  180-240   240-300
Summer          13.5    12.6    10.4     8         7
Winter          16.2    15.3    12.8     12        9.8  
Fuel Map        9       9       8        8         7
MultiplierS     1.5     1.4     1.3      1         1
MultiplierW     1.8     1.7     1.6      1.5       1.4
RPM             1500    1400    1300     1200      1100

etc. etc. till it reaches idle RPM (usually anywhere between 850-900 for us). As you can see, the amount of gas injected (and not burned completely) is much higher in the winter. If you are starting your commute when the car is not fully warmed up, it might be causing a good bit of fuel to be dumped (the fuel flowing till it warms up, even if you are driving it, will be much higher in winter till it warms up). The larger injectors are not as good at flowing small amounts of fuel, so some of it goes our of your tail pipe or into the oil.

I still like the theory that gas is blowing past your injector seals into the heads though.... maybe something got lodged down in the head itself around where the o-rings are causing a small gap.

[Sabre]

Adding one more data point:

The car feels better and accelerates faster on partial throttle. I don't get any more gain on full throttle, in fact it seems slower as well. Tip-In table adjustments?

You are probably running lean.... You REALLY need to get it retuned for the different sized injectors.

[drwrx]

Awesome post and information!

[Phibs]

During start up (this is especially so during cold days) the engine is throwing LOT's of fuel at idle till the car starts up. This is to help it idle smoothly and warm up quickly (I can show you just how much fuel sometime by showing you the maps in my Hydra). Think of it like a choke in old cars. The time that the dumping fuel to warm up varies according to how fast your car heats up. In the summer, the car doesn't need to do this very long, so a 30 second warmup time (aka, the time that During this time, the ECU is taking the amount of fuel that it needs to idle(X) and richening it up by a percentage (Y). So you have throttle position (essentially) x Y =Fuel amount flowed (Z). If you are not allowing your car to warm up more during the winter, this time increases that it multiplies your throttle input's by. In this case, you could very well be going to work while it is still doing it's nice little mulitplying. It is a decaying function, so as time goes on, the multiplier goes down.

Put simply(these numbers are made up since I don't know the scaling factor, but the results are the same)

Code: Select all

Time             0-60   60-120  120-180  180-240   240-300
Summer          13.5    12.6    10.4     8         7
Winter          16.2    15.3    12.8     12        9.8  
Fuel Map        9       9       8        8         7
MultiplierS     1.5     1.4     1.3      1         1
MultiplierW     1.8     1.7     1.6      1.5       1.4
RPM             1500    1400    1300     1200      1100

etc. etc. till it reaches idle RPM (usually anywhere between 850-900 for us). As you can see, the amount of gas injected (and not burned completely) is much higher in the winter. If you are starting your commute when the car is not fully warmed up, it might be causing a good bit of fuel to be dumped (the fuel flowing till it warms up, even if you are driving it, will be much higher in winter till it warms up). The larger injectors are not as good at flowing small amounts of fuel, so some of it goes our of your tail pipe or into the oil.

I still like the theory that gas is blowing past your injector seals into the heads though.... maybe something got lodged down in the head itself around where the o-rings are causing a small gap.

Cool I understand now. Andrewtech installed both my old injectors and the new Deatschwerks, wouldn't they have noticed something? I am getting it retuned asap, and I will do some wideband logging as well even though it will be post CAT. Also they did a compression test which would show leaky cylinders, and it was 150 PSI all around.

[Phibs]

So I noticed something interesting, during a start in the morning after the car has sat all night, it makes the same sound as when andrewtech turned it over manually w/ a wrench as to not hydro lock the engine, ie it sounds like it might be leaking when the car is off. Possible causes?

[complacent]

So I noticed something interesting, during a start in the morning after the car has sat all night, it makes the same sound as when andrewtech turned it over manually w/ a wrench as to not hydro lock the engine, ie it sounds like it might be leaking when the car is off. Possible causes?

I'm pretty sure I mentioned that possibility to your earlier in your troubleshooting...

But to be honest, I'm not sure what could be causing fuel to get into the car while it's off. I don't think the fuel pressure stays constant when the car is off... That being the case, the only way for fuel to make it into the cylinders is through the fuel rails and the injectors.

Either some fuel is slowly seeping by the injector and into the cylinders, or something electrical is allowing an/or multiple injector(s) to seep fuel.

You're rapidly exceeding my area of expertise in fuel systems, particularly Subaru ones. Perhaps a trip back to a shop? Mebbe even the dealer?

I wish I could offer more insight, but I just plain don't know.

[Phibs]

Yes it's going back to the shop but I hvae to find someone to help me drop it off, otherwise I woulda taken it back a month ago

[avriette]

Also they did a compression test which would show leaky cylinders, and it was 150 PSI all around.

Something's not adding up here. If this is the normal compression (and I don't know if it is), then there's no reason fuel should be getting past any more than it should be in, e.g., my car.

When they did the compression test, did they just do it once, or do it a couple times with the pistons in different places? There might be irregularities in your cylinder walls (it's a stretch, but like I and everyone else has said, this doesn't add up).

[complacent]

Yes it's going back to the shop but I hvae to find someone to help me drop it off, otherwise I woulda taken it back a month ago

If you can drop it off after hours, I'll help ya get back home one evening.

[Phibs]

Yeah that'd be cool. I'm hoping I can drop it off before I leave for Ireland this Friday so they can have it for a week. I'm gonna ask my bud first if he came back from Canada but I appreciate your offer and might take you up on it.