Hello,
I Have a 94-95 Volvo 850 NON-TURBO that wont stay started.
Ive tryed changing the fuel filter, Fuel Pressure Regulator,
and Catalytic Converter with no luck. It runs but Idles at
about 500 Rpm for around 30 seconds before shutting off.
Only way to keep it started is to hold the Gas Pedal.
Any Ideas??

 

Any chance you have a check engine light on ??

You might want to pull out the idle air control motor, Volvo has a different name for it but it's what controls how much air gets to the engine to control the RPM's at idle only.

You can use regular carb cleaner to clean it out and you might want to use a Qtip to do a little scrubbing but be gentle. That and remember to keep the motor upright so the cleaner saturates the shutter and doesn't run into the electrical motor that moves it. If you take it off and look into it you'll understand

In the picture it's located at the bottom in the center. If you follow the throttle cable forward it's pointing at it.

 

Thanx for the reply.

Yes the check engine light is on. Ill try cleaning
out the IAC. Ill let yu know if i had any luck.

Also i forgot to add that when i bought the car
there was no Air Filter in the Air Box which means
the previous owner was driving this car without
an air filter :/

 

Well I guess that's a good thing it isn't a turbo or all that crud would have been eating away the inducer. Ya still have to wonder if it's some clown thinking they're getting more power or just too cheap to replace a badly clogged one

If you can two foot it to keep it running at stop lights you should try to get the codes read at a parts store if you have the OBDII or you could just pop open that diagnostic panel under the hood and read them there at home.
The code(s) might be really helpful in case it turns out the IAC is good.

 

Well i cleaned the IAC as good as i could. No Luck :/

And im kind of afraid to risk driving it down to Autozone. (Its Not Registered)

Any other ideas?

 

Read the codes at home from the panel.

How to Read Codes

To start, the Ignition key must be in position II, engine not running. Open the hood. Locate the two diagnostic sockets just inboard of the washer fill cap. The “A” connector (shown above) has a jumper that is stored in the lid of the “A” diagnostic connector. The jumper is used for both diagnostic connectors.
What Codes You Can Get

Listed below is the information retrievable from the various connections.

• A1 Transmission
• B1 Climate Control
• A2 Fuel System
• B2 Cruise Control
• A3 ABS
• B5 SRS
• A5 TCU (Transmission Control)
• B6 Power Seat
• A6 Ignition System
• A7 Combined Instrument

How to Use the Jumpers

Normally “Check Engine Light” information will be found in A2. Put the jumper into A2 and push the black button for one second. Count the red LED light as it blinks back information, blink, blink, pause, blink, blink, blink, pause, blink, blink, is an example of the response you would receive. 2-3-2 would be the code retrieved, now push the button again for one second, again count the blinks, keep checking for codes until one of them repeats, this means you have read all the codes.
Clearing Codes on your 850

Now to clear the codes, push and hold the button for 6-7 seconds, release and as soon as the LED comes on push and hold the button for another 6-7 seconds. Now push the button for one second and read the codes again, you should get 1-1-1 (no faults).
You Must Read All Codes before Clearing

Turn the ignition off and then start the car, the check engine light should be out. It is always a good idea to check for codes, clear them and then drive the vehicle to see if they return before replacing parts. The transmission can ask the check engine light to be turned on, so if you try clearing A2 codes and they wont go away try reading the transmission (A1), clear them , and then go back to A2.

Web site with list of codes to decode the code ;-)
http://www.matthewsvolvosite.com/read-codes-volvo-850

 

Thank you.

Here are my codes:
*121 Solenoid S1 short circuit to ground or control module fault.
*411 TP sensor signal.
*223 IAC valve opening signal.

Not sure what these codes mean.... :\

 

throttle position sensor
idle air control

replace those.

 

It would be good to clear the codes and see if they come back. If so, replace the TPS and Idle air control if their codes pop up again.