Engine bogging & dies

[stucksube]

Hey all,

I have a '97 Impreza that I bought from my brother, who was the second owner, about a year ago. He's a computer, not a car, guy, so the routine maintenance might have been done. But maybe not, or maybe only partially. It started bogging down at low idle about two months ago and about a month ago it would only idle at relatively high RPM and the check engine light came on. It hasn't moved since I got it home.

 

Today, it starts and runs normally for about 15 or 20 seconds and then boggs down and dies. It feels like it's gasping, like it wants to run but is starved for fuel or air. I don't know if/when the fuel filter has been changed and the air filter is not brand new (I only glimpsed it through a crack), but it doesn't look dirty enough to entirely restrict air. I tried slightly cracking open the air box to let air in around the filter but that had no effect.

 

Any suggestions folks? I'm reasonable mechanically inclined, have or can get the tools I might need and have room to work on the car.

 

Thanks,

 

Stuck Sube

[Olnick]

Welcome to the USMB, Stuck Sube!  You've found a great resource here--but please post your questions in the New Generation Forum--that's the place to get "technical help."

 

Good luck!

[stucksube]

About 2 months ago my ’97 Impreza started to nearly stall at
low RPM after the car had been running for around 45 minutes or so, after it
was warmed up. It gradually got worse and did stall several times over the
course of about a month. I could keep the engine running at relatively high
(not screaming) RPM, but it was dicey. And then it got a lot worse all at once,
only ran at high RPM, almost no power and the check engine light came on. I got
the car home but it hasn’t moved since.

 

Right now the car starts right up and runs normally for
about 20 seconds, boggs down and then stalls out. Depressing the gas pedal has
no effect and the check engine light is off, it only came that one time. It
feels/sounds/seems like the engine is gasping, like it wants to run but can’t.
To my old self that suggests a restricted fuel or air supply; as in clogged
filters. The air filter isn’t brand new but it’s not filthy clogged. Fuel
filter maybe? Dirty fuel supply system perhaps?

 

I’m the cars third owner (my brother was No. 2), so I can’t
verify that it’s always been maintained on schedule but I had it checked out by
a reputable Subaru guy last fall who told me that the car was in good
condition. There are about 120,000 miles on it. Besides this problem my Impreza
has been a very durable car for almost 20 years and it should have a bunch more
in it, I hope.

 

Any suggestions anyone?

 

Thanks,

 

Bob

[stucksube]

Thank you. I moved it to the New Generation Forum. Please weigh in any and all.

[wotdsm]

It could be any number of things unfortunately...

Pull codes. There could be one stored in the module that will point you in the right direction. 

[turbosubarubrat]

Get your codes read. It sounds like a dirty iac (idle air controller) or bad hose going to it from the intake boot.

[wtdash]

^+1

 

To start:

- Fuel filter

- CTS - Coolant temp sensor

- Tune up - wires and plugs

- MAF (but not likely unless it dies w/out warning)

 

Also, 120K is past due for timing belt/WP/Tstat/Pulleys.....if not done @ 105K.

[1 Lucky Texan]

good posts

 

timing belt system is a priority.

 

another sensor worth investigating is the knock sensor - but symptom more closely matches engine temp sensor.

[Olnick]

How many miles on the car?  Any idea when it last had a tune-up?

 

I'd definitely start with new air and fuel filters.  New plugs and wires too (use NGK plugs and NGK or OEM wires only.)  Clean the IACV.  Replace the PCV and clean the hoses that connect to it. 

 

Let us know how it goes . . . and good luck.

[Olnick]

The ECTS (Engine Coolant Temperature Sensor) is a good possibility.  Worth replacing.

 

And definitely do the Timing Belt and front end--unless you know it has already been done.

[Bushwick]

Would really help to know which code it had as that's be a definite pointer in the general direction of what to tackle 1st. 

 

As others stated, timing belt should be replaced if original. Fuel filter could be clogged, but to do that to your engine at that mileage, you'd almost need a crazy ex to dump sugar or even gobs of dirt in the tank, but that'd most likely clog the pump's sock up.

 

Your fuel pump could also be failing from some unknown reason. Sometimes they'll fail but keeping the pedal pressed will allow it to run rough.

 

You don't have any disconnected sensors, unhooked MAF, a pod air filter, etc.?

 

I'd start with the basics and do a full tune-up ($50 worth of parts and you rule out so much more) and timing belt and see if it'll run better. If it doesn't change at ALL, then you likely have a fueling or ignition issue, which can be as simple as a CPS sensor going bonkers (a multi-meter can check it's values) or fuel pump, MAF sensor, etc. Hopefully it's not an actual issue with the mechanical side of the engine.

Edited April 21, 2016 by Bushwick

[stucksube]

There are 128,000 miles on it.  I just located the original maintenance book that says the last time it was serviced by the dealer was at 90,000. Unfortunately, that's likely correct. So it's waaay overdue.

 

The check engine light only came on once. But it may just be that the car will not run long enough (before it stalls) to trigger the check engine light to switch on. Can codes be read/scanned if the check engine light is not switched on?

 

I'll get to work on that list of things to check/replace; the filters, plugs and wires this weekend. Hopefully I can get it back up and running and then get it serviced.

 

Thanks folks, I'll let you know how it goes.

[bakedpotatoechips99]

An inline Fuel pressure gauge would allow you to get readings before replacing anything. But that costs more than a new fuel filter. You would want not just the gauge,

 but a "T fitting", some clamps, and some fuel line, to connect to various places under the hood mostly. I had to replace a fuel pump in my old '95 legacy a couple of years ago.

 The gauge really helped me figure it out. If it does not start, you can try some starting fluid spray from a can. But you have to be careful not to spray it on the Mass air flow sensor.

 If the car starts right up with starting fluid, and not otherwise, then you can kind of tell fuel is not really getting to the injectors or through them. But again, you must not spray starting fluid on the MAF

 sensor, and you only spray just a bit (read the can), as it is more volatile than gasoline. That is how I determined initially that I had a fuel delivery problem, and I think I checked the relay 1st. Then finally connected a

 pressure gauge, and, with zero fuel pressure, realize the pump needed to be replaced. Not to difficult, there's an upper fuel pump access panel with tiny Phillips head screws under the carpeting in the rear interior,

 So the gas tank does not need to be removed like some cars in the past. Bring a fire extinguisher if you can.

[stucksube]

Thanks all. So far, it was rainy over the weekend here in Seattle, I've replaced the air filter and plugs. I didn't use anti-sieze on the plugs because I forgot. I still could when I swap out the plugs. The battery and windshield washer bottle are still out but I'd rather not mess with the plugs now that they're in. One of the old plugs was not screwed entirely into the head and did have some gray gunk on it when I pulled it.

 

I have the wires, a new fuel filter and a new PCV that I'll get too probably by Tuesday (still raining today). I don't think that this car has been tuned up for about 26,000 miles. I'm thinking that the PCV might be ancient and gunked up to the point that it's screwing things up. I'll know so enough.

 

The car does start and run OK for about 15 - 20 seconds and then stalls.

[stucksube]

I meant to say that I could re-install the plugs when I replaced the wires.

[1 Lucky Texan]

meh - if you used the recommended NGK plugs, they actually warn against using anti-seize.

 

I wouldn't pull them. crush washer already crushed and the more you handle them, the more likely to bend an electrode or crack porcelain.

[stucksube]

4/26 Update: The plugs and wires are replaced (NGK w/o anti-seize) as are the air and fuel filters and the PCV. One of the plugs was kind of gummy. The PCV was also a little gummy, but not stuck open/shut.

 

I'm going to assume that nothing was done to the car between 89,000 and 128,000 miles, I have nothing to suggest otherwise. Which means that the front end has not been done, unfortunately. That sounds daunting.

 

The car might run a little better, maybe. Or maybe not. It runs for closer to 45 seconds before it stalls, where it used to only run about 15 seconds before stalling. I could probably keep it running if I kept the RPM's up where I couldn't do that before. The engine would just bog down and die without reving up. The check engine light did turn on today, which only happened once before.

 

I think next up is replacing the ECTS and cleaning the IACV while I figure this timing belt business out. It sounds like the fuel pump could be an issue.

[stucksube]

The ECTS is replaced and IACV cleaning is on deck.

 

Because my Sube won't run for any duration, my plan is to spray a little TB cleaner directly into the IAC (via a removed hose) while the engine is off and then turning it over. I'll probably repeat that a couple/few times. In my '97 Impreza, I've been told (I'll go look right now) that the IAC is located not on the TB, but beneath the PCV, which I've already replaced. 

 

I've also read that it's worth spraying sea foam into the PCV to clean out the system 'downwind' from that point. I think I'll do the sea foam first, followed by the IAC cleaning.

 

Any comments/suggestions/advice/warnings out there that I should know about?

[heartless]

get your hands on a code reader and read the stored codes asap

 

right now you are just throwing parts at it hoping for a solution. find out what the codes are so you have a better idea of what is happening and what direction to go. and yes, it will store codes without the CEL being on

 

the only other thing I would be doing at this point is getting a complete timing kit ordered for it as that would be a priority item if it is overdue.

Edited May 5, 2016 by heartless