'98 Windstar stalling & running rough
pmaloney
10-18-2004, 08:37 PM
Sometimes the 3.8L engine stalls while stopped at lights, in gear, and either just about to stop, or just starting but before you move you foot from the brake to the gas. Happens in drive-thrus too, and really annoying.
Also, sometimes when starting the motor, it rally runs rough for a little while. Feels and sounds like it's only running on 4 of 6 cylinders or something like that. It clears itself up if you rev it up and own for a bit though.
It was doing this for a few weeks off and on, and them my check engine light came on. So we took it to the shop and he put the little scanner thing on it and told us that it was saying that both oxygen sensors were gone. He also said that that was odd, as it's a '98 and only has 140k on it.
I do't know if it's realted or not, but I suspect I also have a vacuum leak somewhere becasue my heater & a/c only blows through the defrost and foot vents (separate post about that since they may or may not be related).
Anybody have any other ideas as to what it might be? My mechanic said the sensors are about $130 CDN each.
Any tips appreciated.
Also, sometimes when starting the motor, it rally runs rough for a little while. Feels and sounds like it's only running on 4 of 6 cylinders or something like that. It clears itself up if you rev it up and own for a bit though.
It was doing this for a few weeks off and on, and them my check engine light came on. So we took it to the shop and he put the little scanner thing on it and told us that it was saying that both oxygen sensors were gone. He also said that that was odd, as it's a '98 and only has 140k on it.
I do't know if it's realted or not, but I suspect I also have a vacuum leak somewhere becasue my heater & a/c only blows through the defrost and foot vents (separate post about that since they may or may not be related).
Anybody have any other ideas as to what it might be? My mechanic said the sensors are about $130 CDN each.
Any tips appreciated.
wiswind
10-18-2004, 10:28 PM
#1. Verify that you do not have any vacuum leaks. The heater controls end up being vacuum actuated. There are a number of vacuum connections on the BACK of the upper intake manifold.
http://community.webshots.com/album/201931518cScpNK
should lead you to pictures of some views of my '96. There is a picture from the bottom side of the upper intake manifold.....and you can see the vacuum connections there....verify that each is firmly connected.
Vacuum leaks are VERY common on the windstar. Also check the PVC line from the valve (on the back valve cover) to the elbow on the top of the upper intake manifold (my PCV elbow got a crack on the inside).
The '98 is not as prone to the upper manifold leaks as the '99 and later model years.....they went to a different upper intake manifold.....and that caused a number of problems. 1999 was a major change year....so posts about these newer windstars may or may not apply to our older units.
The windstar has 4 oxygen sensors....2 "upstream" (before the catalytic convertors)....and 2 "downstream" (after the catalytic convertors).
You have a dual exhaust....until after the convertors....then they connect together. It is not likely that they all went bad.....Possible....but not likely. I am only mentioning this because.....and I am NOT an expert....but I have read a number of posts of people (and dealerships) replacing the oxygen sensors....and having that not be the problem.
If you have never had your EGR ports cleaned...you are due. Mine acted up for the first time around 135K miles.....I have photos of those posted also. My pictures were too big to post on this site....so I have them on webshots. EGR WILL cause your engine to run rough....the only code that came up for mine was a misfire on cylinder #4.......as that cylinder was the only one still open....and got all the flow.
I have seen prices of around $150 (US) for the cleaning at a FORD dealer....which is reasonable for the amount of work involved......Some people posted prices much higher.....
I did my own.....so is not real hard....Just be carefull to avoid getting stuff on down into the lower intake manifold. I stuffed little rags into the lower intake manifold ports....leaving the EGR ports exposed....then did my work on them.....I removed the EGR valve and the offset spacer that is in between the EGR valve and the lower intake manifold.....and used LOTS of carb cleaner.....and ran a bottle brush (acutally an aquarium tubing brush with a longe flexible handle) up in the passage from the EGR valve side. I put in a new EGR valve and gasket....and a new DPFE...but you may not need to do that.
Bottom line...if the rough idle is not real intermittent....you can remove the vacuum line that connets to the top, front, of the EGR valve...and plug it......and drive the van.....if the problem goes away.....then you know that it is an EGR problem......You should not have any significant vacuum on the line to the EGR valve at idle.
The IAC is known to be a MAJOR cause STALLING problems at idle......
Often, people have been able to clear this up by removing, and cleaning, the IAC. Is not real expensive....and is VERY easy to replace.
2 bolts and 1 electrical connector.
Also, Try cleaning the MAF with non-residue electronic cleaner....as well as the temp. sensor in the flexible air hose that goes from the MAF to the throttle body. Locations of these are shown in my pictures.
http://community.webshots.com/album/201931518cScpNK
should lead you to pictures of some views of my '96. There is a picture from the bottom side of the upper intake manifold.....and you can see the vacuum connections there....verify that each is firmly connected.
Vacuum leaks are VERY common on the windstar. Also check the PVC line from the valve (on the back valve cover) to the elbow on the top of the upper intake manifold (my PCV elbow got a crack on the inside).
The '98 is not as prone to the upper manifold leaks as the '99 and later model years.....they went to a different upper intake manifold.....and that caused a number of problems. 1999 was a major change year....so posts about these newer windstars may or may not apply to our older units.
The windstar has 4 oxygen sensors....2 "upstream" (before the catalytic convertors)....and 2 "downstream" (after the catalytic convertors).
You have a dual exhaust....until after the convertors....then they connect together. It is not likely that they all went bad.....Possible....but not likely. I am only mentioning this because.....and I am NOT an expert....but I have read a number of posts of people (and dealerships) replacing the oxygen sensors....and having that not be the problem.
If you have never had your EGR ports cleaned...you are due. Mine acted up for the first time around 135K miles.....I have photos of those posted also. My pictures were too big to post on this site....so I have them on webshots. EGR WILL cause your engine to run rough....the only code that came up for mine was a misfire on cylinder #4.......as that cylinder was the only one still open....and got all the flow.
I have seen prices of around $150 (US) for the cleaning at a FORD dealer....which is reasonable for the amount of work involved......Some people posted prices much higher.....
I did my own.....so is not real hard....Just be carefull to avoid getting stuff on down into the lower intake manifold. I stuffed little rags into the lower intake manifold ports....leaving the EGR ports exposed....then did my work on them.....I removed the EGR valve and the offset spacer that is in between the EGR valve and the lower intake manifold.....and used LOTS of carb cleaner.....and ran a bottle brush (acutally an aquarium tubing brush with a longe flexible handle) up in the passage from the EGR valve side. I put in a new EGR valve and gasket....and a new DPFE...but you may not need to do that.
Bottom line...if the rough idle is not real intermittent....you can remove the vacuum line that connets to the top, front, of the EGR valve...and plug it......and drive the van.....if the problem goes away.....then you know that it is an EGR problem......You should not have any significant vacuum on the line to the EGR valve at idle.
The IAC is known to be a MAJOR cause STALLING problems at idle......
Often, people have been able to clear this up by removing, and cleaning, the IAC. Is not real expensive....and is VERY easy to replace.
2 bolts and 1 electrical connector.
Also, Try cleaning the MAF with non-residue electronic cleaner....as well as the temp. sensor in the flexible air hose that goes from the MAF to the throttle body. Locations of these are shown in my pictures.
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