98 Windstar Limited 3.8: Codes 171 & 174 related to stalling?

[QCubed]

My 98 Windstar Limited started to stall once in a blue moon a few months ago. Didn't think anything of it at the time. Then couple of months ago CEL came on. Got OBD codes 171 and 174. I have been reading all the great threads about these codes, but I have not found even one mention of Windstars with these problems stalling. So I'm wondering: is the stalling related to these error codes, or a different issue altogether? All input sincerely appreciated. Thanks!

[Airjer_]

I have had them idle really ruff but I can't think of one that would actually stall. I suppose its not impossible but a vacuum leak that large you would certainly hear!

[bdahl385]

Originally Posted by DipakG

My 98 Windstar Limited started to stall once in a blue moon a few months ago. Didn't think anything of it at the time. Then couple of months ago CEL came on. Got OBD codes 171 and 174. I have been reading all the great threads about these codes, but I have not found even one mention of Windstars with these problems stalling. So I'm wondering: is the stalling related to these error codes, or a different issue altogether? All input sincerely appreciated. Thanks!

We drove our Winnie for many months with the 171/174 CEL w/o any performance or gas mileage issues. I agree with Airjer that you would have to have a really massive leak on those intake gaskets to kill the engine.

I would first clean or check the IAC valve, this will definitely kill the engine at idle if its not working properly and is a common failure item...

http://www.automotiveforums.com/vbul...d.php?t=960291

[northern piper]

I'd be betting something other than the 171/174 is causing the stall. Vacuum, as mentioned earlier, is likely the culprit. Do a really close check on all vac lines THEN do the 171/174 fix if you haven't already.

[QCubed]

Thanks for your replies everyone! I will check the IAC and the vaccuum lines and get back to you. By the way, I should mention this as I don't know of it makes any difference, but the stalling seems to happen either when braking to a stop, or when stopped for a while (e.g. while waiting at a red light.) Thanks again!

[Gobbler865]

Mine used to do this as well BEFORE I did the isolator bolt and seal changeout. NOW...she's run so quiet, I can't tell if she's on anymore. She purrs like a kitten!

Mike

[QCubed]

Glad to know things worked out for Mike! I could even be a little envious actually!

Someone please correct me if I'm wrong, but doesn't the isolator bolt and seal issue apply to 1999 to 2003 models? I thought that the 98s and older Windstars came with a different engine and so did not suffer the isolator bolt and seal problem.

[QCubed]

No replies yet ... anyone?

[Freakzilla69]

I had the same stalling at a stop problem. Definately clean the IAC.

The isolator bolts aren't an issue on the '98 but the fix is still a good one for cleaning out your EGR ports. Clean the upper and lower intake manifold very well, too. I used Seafoam and carb cleaner... and a hose. It was filthy.

Chances are you might have a clogged vacuum line too. Get a vacuum tester and a diagram (I thing the Haynes manual has one) and check the vacuum at the upper intake manifold on the back, the manual should give you a range. If that's good check the vacuum at the end of each vacuum tube from there, especially the Fuel Pressure Regulator, Exhaust Gas Recirculation Valve, IRMCs, Break Booster and the Vacuum Reservior. If you have a clogged line, you can get replacement tubing and connectors at the parts store.

Check your PCV valve too.

Good luck.

[Freakzilla69]

98E03 Emissions Recall relates to this issue, I started a topic on it.

[serge_saati]

Originally Posted by DipakG

So I'm wondering: is the stalling related to these error codes, or a different issue altogether? All input sincerely appreciated. Thanks!

Yes, it does. A too lean mixture can cause an unstable idling (500-700rpm), and may cause the van to stall.

I had a vacuum leak in a Windstar 99. When I turn on the A/C at idle, engine oscillate between 500 and 700 rpm. 500rpm is the limit before stalling, so it's possible to stall.

Do the vacuum test to see if it's the real cause of your stalling, it may be something else.

But you should also repair your vacuum leak. If not, engine may break. I suggest you to bring it in a Ford Dealership, not to a standard shop. But if you are very good in mechanic, you can replace the intake port gasket. This Website will help you: http://www.leckemby.net/windstar/windstar01.html