[soyer38301]

Hello everyone,

I have a 97 850 that has started running extremely rough when the temperature is below 32 F (or so it seems). The last time it did this I changed the plugs out and it was "corrected". This time it was not the case...

When you can get the car up to speed (around 50 mph) and back off the accelerator it seems to even out and run smoother. When you take off from a dead stop it is almost like it is only running on 3 cylinders and "pops" back and forth running rough and then smoother as you slowly pick up speed.

I have tried injector cleaner which has not helped. As stated before I did change out the plugs (twice) but that did not help either.

I am at a loss as to where to start looking .. any thoughts and guidance would be appreciated.

Scott

 

[BHart]

One possible fix could be a professional fuel system clean. Most shops offer this for $50-75. It does work, I've seen it myself and was previously hesitant to pay for 'snake oil'.

Ignition could be part of the problem too. Cold weather means condensation - does the car run well when it's fully up to temp? If it does, try spraying some water with a sprizer bottle on the plug wires and see if it re-creates the problem.

 

[soyer38301]

It actually looks like it might have been the IAC -- cleaned it and ran it for a while and it seems to have taken care of the issue. I will know more tomorrow when I get to drive it for an extended time. Did not get a chance today as it was my daughters "college visit day -- meet the soccer coach..."

Thanks.

Scott

 

[Admin]

When you replaced the plugs what was the condition of the plugs you removed? If you replaced them a couple of times and each time it runs well I wonder if the plugs are getting fouled out with an injector/fuel mixture issue.

 

[soyer38301]

This last time the plugs were actually in very good condition.

That being said after cleaning the ACI it is still doing the same thing. Seems to be strictly an outside temp thing. Does not seem to matter if it is wet or not, just below 32 deg F and it runs like crap.

Scott