sputtering and jerky idle

[Landshark]

thanks, Tim - now i don't have to look it up.

[pylon500]

so wait....did cleaning the ecu harness work or not?

Well, previously, the car seemed to run badly more than it ran well.
So on the day I tried cleaning what contacts I could find, the first time I started it, it ran beautifully! AND for about the next week!
But, the rough running is starting to come back, but not nearly as often!
At least now I just live with the problem and don't abuse the engine or gearbox to get a stall and reset.
I'm gunna have a look at this multiple grounding thing?
Arthur.

[oab_au]

I notice that at least two, Arthur and Maximvsv, have the pop up dipstick happening, I think this is related to the idle problem, and also to the many oil leaks, that some have.

I'll explane, the crankcase ventilation system, has two phases of operation, idle/part throttle operation, with manifold vacuum, and full throttle operation without manifold vacuum.

When there is manifold vacuum, the engine pulls air from the air box in front of the throttle body, by-passing the idle control system, through the engine up through the PCV valve into the manifold to be burnt in the engine. This amounts to a controlled air leak into the engine, that has an effect on the idle speed. The ECU knows about it, so it is expected to be there. If it is not, the idle will be lower, and the ECU will try to compensate with the idle control valve. This can be checked for by removing the oilfiller cap, with the engine idling, place you hand over the pipe, see if you can feel a vacuum pulling on your hand. If it is, then the engine breather system is blocked. Contary to popular opinion, there should not be a vacuum in the crankcase, air should be flowing through there.

Under full throttle conditions, there is no manifold vacuum to open the PCV valve. Under these conditions there is a far amount of gas blowing past the piston rings, with the valve closed the gas pressure, then has to flow from the crankcase up the two breather pipes connected to the cam covers, to a tube in the bottom of the air box, this passage is connected to another small angled pipe that connects to the air delivery pipe on the right hand side of the air box. If this passage in the bottom of the air box, or the small hole that connects that passage to the small angled pipe is blocked, the crankcase is sealed and the gas pressure will build up to force oil out every seal and gasket, force open the PCV valve and PUSH THE DIPSTICK UP.

Having read the many reports of gummed up throttle bodies, I have no doubt that these passages would get blocked as well. I reckon that it would be worth checking this out, if you have idle or oil leak problems.

Harvey.

Alright, I have got a 5 speed SVX and my car just started freaking out today with the whole sputter/stall syndrome. I have swapped out my ECU with my other SVXs and put in the stage 2 ECUtune chip, great work by the way, and it drives GREAT until it warms up. Then it gets rather spastic with occasional bursts of jerking while driving, only under about 3,000 RPMs, Now I figure it could have a combined Issue of being a Petroleum related problem along with the warmer temp. My EG33 felt really hot compared to normal, and I just did the oil change and new coolant. I think that I may have some sort of answer. I am going to follow in a members footsteps using the "Restore", Fuel Injector Cleaner, Fuel System Cleaner, and then Moving up to Mobil1 Synthetic 10W40. On top of that I am going to possible work with the thermostat housing and making it open at a lower temp. Because it seems that it is quite temperature related, so those are my steps and I will definately keep you posted and thanks for everyones inputs and ideas.

Craig Kasten
Empirical Motorsports

[mbtoloczko]

Might want to try dumping in a gallon of toluene (to 10 gal of gas) instead of the other fuel cleaner additives. Somewhere on the site, there is posted the results of a study on cleaning effectiveness of various additives, and toluene was among the best. Most of the store-bought items ranked low.

Alright, well I added that stuff tried it all out anyway, by the time I got a reply I had bought it. It seemed to help a little, but then I was talking a a buddy of mine and he said that he had some of the same symptoms in his built up pick up truck, and his only problem was a leaking gas cap. This could have easily been the case because my issue started as soon as I left the vehicle testing station, after they had done the gas cap testing. So...I cranked on my gas cap and low and behold the activity seemed to simmer down substantially, I mean my engine and fuel lines are still working out the air bubbles, but I think that this may be what some of the other guys are experiencing, maybe it's just time for a new gas cap. I mean I haven't read any thing about people changing their's out or anything, but hey, it was just a good feeling to know it wasn't that serious.

[Gargoyle]

Ok well I am most unpleased to be joining this thread.

But just today my sweet sweet dream machine had a hiccup followed by ruff acceleration ( idel is around 500 RPM's ) & sounds like its fireing on 4 of 6 No check lights No codes but stoped at a light it sort of lopes ( rocks like an old V-8 ) & if reved up she sounds like she is missing Bad. If it where an old chevy I would think either vacume or jumped time But she aint no old chevy. & with only 56,700 miles on her I am praying It's something findable.. Anyway She has not yet cooled all the way down to see if its a warm only thing but I have made an appointment with Smart Service ( Independent Subaru Expert ) for tuesday So if they can fix her ( Pleeeeeeeease ) I will let you know what they had to do..

[Earthworm]

It does almost sound like the timing belt jumped.

No Check Engine Light?

[Gargoyle]

Ice cold she still sounds the same.. I tryd pulling the injector clips & # 3 made no differance the others allmost killed her so perhaps thet injector ? Any way I will find out tuesday & a few if not a few more hundred dollors from now.. Damn the Ol Buick drives like a freaken Trash truck

[halistan]

I'm surprised none of the other older members jumped on this. Its a pretty common problem with the SVX. Just clean your throttle body. It takes about 1-2 hours and a can of carb cleaner. Save yourselves a lot of money and clean that first. Its not an O2 sensor, a fuel pump, loose exhaust or anything else. Just a little dirt.

This is making me think that we need a document of common problems with the SVX and thier fixes. I know not all of you have been around as long as some of us so its not your fault. This is a hard car to diagnose. I seem to remember one of the guys with something like that already but can't remember where i saw that. I'll look around for it and get back to you or if someone else know...they are free to chime in and add thier $.02.

Originally posted by Ron Mummert
Not to tell everyone that I have THE SOLUTION, and I've never had the problem as described by all of you with my SVX, but DID have the identical symptoms with my '88 Voyager van a few months ago. I took the cheap route first, & thoroughly cleaned out the throttle body "butterfly" area with plain old carburator cleaner spray. It was REALLY dirty. I sprayed the intake generously while running the engine & goosing the throttle. I also poured Techron cleaner in the gas tank. After this ten dollar tune-up, I took her out & drove her hard for a few miles.
Since then the old 170K plus van runs like new.
Who knows? - it's worth a try.

Ron (Mopar master mechanic).

[Gargoyle]

Originally posted by halistan
I'm surprised none of the other older members jumped on this. Its a pretty common problem with the SVX. Just clean your throttle body. It takes about 1-2 hours and a can of carb cleaner. Save yourselves a lot of money and clean that first. Its not an O2 sensor, a fuel pump, loose exhaust or anything else. Just a little dirt.

Well Being one that will try anything once I tryd it & drove her hard for about 45 min & NO change.
she still sounds like # 3 is not firing. any way will post Wedensday ( or late Tuesday with what the shop tells me

[svxistentialist]

I had rough idle, poor throttle response, cutting out in traffic, you name it, serious bad running with my SVX.

Principal suspect was bad earth/connections, possibly to the ECU. Took it all apart, could find nothing obvious. Replaced the air flow meter [MAF sensor] with the one from a parts car I bought, instant solution.

I kid you not, the car is flying like a bird, after weeks of breaking my heart.

Don't disagree with anything said above, clean the throttle body, use a good fuel additive, check the PCV system for correct operation. It is a hard car to diagnose, and any of these could be the problem, or contributing to it.

If you car is pulling clean at high revs, over 3.5 or 4K, but *****in about at tickover or on the over-run, then suspect the MAF sensor.

Joe

[want-a-fast-svx]

Originally posted by Gargoyle
Ice cold she still sounds the same.. I tryd pulling the injector clips & # 3 made no differance the others allmost killed her so perhaps thet injector ? Any way I will find out tuesday & a few if not a few more hundred dollors from now.. Damn the Ol Buick drives like a freaken Trash truck

Doesnt this sound like the solution to your problem? If you pulled them all and thats the one that didnt do anything its probably a faulty coil pack. Did you do your plugs recently or fiddle with any of the coil packs? I know that some members have had problems with them after plug changes and what not. Anyone near you with an svx that could lend you a coil???

[Gargoyle]

Well I got the call from Smart service yesterday & It seems that 1 of my coil packs went out on me. ( it allso had stored fault codes for when I pulled the injector clips & when I cleaned out the throttle body & disconected the mass air sensor * he told me me it allso showed old codes for bad front & rear O2 sensors * the coil pack is gonna cost me around 160 + labor ( he was worried it may need the mass air & that is $ 400 but I'm allmost positive thats ok as It showed in memory from my pulling it. Any way they had to order the part so assuring me it would get parked inside ( it was I checked lol ) I am hoping to get my baby back today ( Friday at the latest ) God I knew I loved her but had no idea the seperation Anxiety could be so bad

[Gargoyle]

Well I got her back yesterday So after 3 days & 2 nights locked in the service bay The $ 318 I payed in ransome Is money well spent she once again is runnen like New..
It was just a coil pack that went in my Instance so I feel lucky .... Gosh but I Love this car