[hoelscherlj]

Hello folks, having a rough idle issue. I'll start by what I have done to this van since I aquired it...
Replaced both head gaskets
Intake gaskets twice
Decarbonized the intake
Replaced plugs and coil
Fuel Filter
PCV valve
Ultrasonically cleaned injectors and replaced the number 4
Replaced entire front suspension and rear shocks
checked all vaccum lines
replaced alternator
checked fuel pressure


I currently need to replace one of the O2 sensors as it has popped a code.I imagine the coolant leak I had caused that. I managed to round it out because I couldn't get a good grip on it.

The problem I am having is an erratic idle and low speed driving. Highway speeds the engine runs smooth as silk. I ohmed the plug wires out and they seemed okay although they look like the original set and probably need to be replaced.
I'm not popping any other codes except for cylinder 4 misfire occasionally when it gets really bad. I can smell a strong fuel smell in the exhaust when it idles rough.
This seems to happen as it warms up. I used a timing light to check the spark and notice the spark seems to drop out sporadically, usually in time with the misfires. It happens on all cylinders in the front and I haven't had the cowl off latley to check the rear cylinders. I also tried this on my neigbors windstar to verify the timing light and it was working fine on his.

I'm at the end of my experience level here and would appreciate any advice.

I plan to verify my wires with my friends van as my wife won't let me throw any more money at this van at the moment. I have the O2 sensor and plan to remove the exhaust pipe this weekend to replace it. If anyone has any ideas as to what to check while i'm out there it would be helpful.
Thanks,
Luc

 

[Poppy]

Certainly there are a few things to look at but I would start with vacuum leaks and cleaning the IAC. Here are some tips.

http://www.fordforumsonline.com/forum/ford-windstar/95-pictures-1998-windstar-vacuum-lines.html

http://www.fordforumsonline.com/forum/engine-drivetrain/94-locate-vacuum-leak.html

http://www.fordforumsonline.com/forum/engine-drivetrain/261-howto-check-clean-your-idle-air-control-valve-iac-iab.html

 

[electro]

Might be helpful to know the number of the code that turned on the CEL.

 

[hoelscherlj]

Its been awhile since I checked the codes so I could't tell you exactly But the two I've seen are for O2 sensor #2 bank 2 and cylinder 4 misfire. I'll be going to the parts store in a while an i'll read them again as the light is still on.
I did manage to change the O2 sensor this afternoon and swapped the wires from my neighbor's van. no change. I still get an erratic spark signal with his wires as well.

I'll post back with the codes this evening

I have cleaned and verified the IAC and vacuum lines are all okay. I didn't think to check the booster though I'll try that this evening as well.

I noticed a light film of oil in the throttle body and the rubber boot connecting the throttle body to the air box. I think I'm going to pick up a couple of bottles of cleaner and hose those out.

Thanks for the replies,
Luc

 

[Poppy]

Another thing to check is your ignition coil

http://www.fordforumsonline.com/forum/ford-windstar/102-howto-check-ignition-coil-pack-3-8-windstar.html

 

[Poppy]

One other thing:
the windstar runs on the waste spark system, in that the pairs of lugs fire at the same time. One is firing on the compresson stoke and the other is firing on the exhaust stoke of the companion cylinder (wasteing that spark).

You could try swapping the wires at the paired lugs and see if the missfire switches to the paired cylinder, if it does its a pretty good bet that its a bad coil.

 

[hoelscherlj]

Think I found the issue...

So I went to check the codes at the local part store after swapping out the O2 sensor. The van ran a little better on the way there. I forund the codes were P0171 P0303 P0402 P0156. I had never had the lean codes before so I never replaced the isolator bolts when I did the other repairs. Seeing as how nobody had them in stock I removed each bolt and isolator, greased the rubber boot and used RTV around the washer and bolt head. Most of the washers were cracked and one had a chunk missing. When I was done the engine ran rather smooth at idle and the spark was steady.
I have the bolts on order and I'm hoping this will be the end of my engine troubles. Now I just need to figure out the clunk I get from the transmission.....
Thanks for the help,
Luc

 

[Poppy]

So now I see that you have a cyl #3 missfire and no #4 missfire. Did you swap the plug wires like I suggested?

 

[Jonzo77]

Did you whack it with a stick, and call it a dirty slut?

It works on most of my vehicles...

 

[hoelscherlj]

So now I see that you have a cyl #3 missfire and no #4 missfire. Did you swap the plug wires like I suggested?

No I swapped the front plug wires with my neighbor to verify them. I'm guessing the EGR issue was causing the missfire. I took the valve off to clean it and I might have knocked some stuff loose causing the issue. On the other hand I am getting a pulsing vacuum draw on the EGR line at idle. I've heard that it shouldn't be activated at idle. Either way it seems to be running okay at the moment, i'll dig into it later if it rears it's ugly head again.

 

[hoelscherlj]

Did you whack it with a stick, and call it a dirty slut?

It works on most of my vehicles...

No but it sure looks like I have!