Bad timing? Rough idle?

[2002windstar]

Hi all, new to the forum, at least in terms of registering and posting.

Great information on this site, it has been nice just to have access to the knowledge base here.

Here is my problem.

2002 Windstar, 3.8L, ~168k. I have emission testing coming up in April and the CEL was on (has been on for a while). The typical 0174, was "fixed once before, 2 years ago by a service center to pass emission at that time, the CEL stayed off for sometime but eventually came back on.

I found this site by looking for have the 0174 "fixed" again and took to the work myself, along with my kid.

We did the upper and lower intake manifold gaskets, IAC gasket, trottle body gasket, since we were "in there" we replaced the coolant by pass tube along with the front valve cover replacement (cover/pcv/pcv tube/fuel regulator tube).

Removed everything and installed everything according to proper procure and to torque specs.

Upon starting the engine back up the idle was/is extremely rough and wants to almost stall when put into drive or reverse. While in park the timing seems to smooth out at higher rpm (2500) but while driving (which I have only done for a short distance < 1mile at 20 mph or less) the is a backfire occurring.

I did double check that all sensors were plugged back in, checked for the presence of a vacuum leak with both throttle body cleaner and a propane bottle that I attached a tube to. Neither test revealed a leak.

So now my thoughts are bad plugs/wires/coil, camshaft synchronizer and after that I am just not sure at this point.

I have an ODBII that I recorded data and something that caught my eye was the difference between fuel bank trims. Also I have 0v on OS22 - bad O2 sensor?

Here is the average data from 68 reading (I can go into each reading for more detail if anyone thinks that will help)

MIL status - off
ABSLT TPS% - 17.3
ENG SPEED RPM - 782
CALC LOAD% - 23.5
MAF LB/M - 0.82
COOLANT (F) - 162
IAT (F) - 39
IGN ADV (Degrees) - 15.5
ST FTRM1% - -2.3
ST FTRM2% - -8.6
LT FTRM1% - -5.5
LT FTRM2% - +24.2
VEH SPEED MPH - 0
FUEL SYS1 - CLSD
FUEL SYS2 - N/A
O2S11(v) - 0.065
ST FTRM11% - +0.8
O2S12(v) - 0.075
O2S21(v) - 0.100
ST FTRM21% - +2.3
O2S22(v) - 0.000
ODB2 STAT - CA


Thanks for taking the time to read this post.

[scubacat]

Did you clean out the little EGR ports while you were in there? Also, are the little white IMRC bushings secure and in place?

[2002windstar]

Originally Posted by scubacat

Did you clean out the little EGR ports while you were in there? Also, are the little white IMRC bushings secure and in place?

Thanks for the quick response scubacat - No I did not clean out the EGR ports on the lower manifold and actually just watch a short video here on it. I have a feeling that will be my next step, should have done it while it was out.

The IMRC bushings are intact. Question - should the IMRC operate if the van is in park and the RPM is brought up to >2000? Or does it only operate if the vehicle is in drive? I did have my kid watch the IMRC while I brought the RPM up and he said that he did not see any movement. (He is 17 and a good helper, unlike my 16 year old )

[2002windstar]

While reviewing the data on my ODBII, O2S22 has 0v and never registered any voltage during the data capture - obviously a problem.

I will check the wires and connection and clean it with electrical connection cleaner and retest, this is the sensor on the cat, if it is in fact bad it is an easy replacement.

Just thinking out load, my LT fuel trims are really high on bank 2 (compared to bank 1) and fluctuate from 3 to over 24 while bank 1 fluctuated from -1.6 to -7.8 a much tighter range.

To be honest I'm not sure which trim level are "normal", if either of them are.

I'm thinking it is not coincidence that I have a bad O2 sensor on bank 2 and my fuel trims are all over the place on bank 2, any input or thoughts?

Still planning on cleaning the EGR ports on the manifold to see if that makes any difference.

[12Ounce]

Up to this point, has the synchronizer been disturbed? Also, can you block open the throttle plate, and do a compression test on all cylinders?

[2002windstar]

Originally Posted by 12Ounce

Up to this point, has the synchronizer been disturbed? Also, can you block open the throttle plate, and do a compression test on all cylinders?

Hey 12Ounce,

No the synchronizer has not been disturbed - I do not have a compression gauge but may need to pick one up. Is your thought, if the synchronizer has not been disturbed then it is not likely the issue?

I should have also stated the this condition was only mildly present prior to the changing of the manifold gaskets but after re-assembly almost renders the van un-driveable. Prior to the change the was never a backfire which now happens occasionally.

Today I am taking the plenum off to clean the EGR ports and going to pull the plugs to take a look at how each one looks.

For under a 100 bucks I can get new plugs and wires (they were done about 67K ago with 100K plugs), a O2 sensor to replace the bad one (bank 2/sensor 2) and possibly a new DPFE which has never been replace.

I do realize I may not need everything but in Ohio if you have spent $300 on emission repairs and it still does not pass (they do an ODBII reading) they will give you a waiver to renew your plates.

With the manifold gasket kit, valve cover repair kit and the above will put me a little above the $300 mark. This will at least allow to get the plates renewed and hopefully help solve my rough idle/timing issue.

[wiswind]

Oxygen sensor #2......located AFTER the catalytic converter should NOT cause any rough idle/bacfire issue.
These are the "downstream" sensors that only monitor the exhaust to verify that the catalytic converters are working.
The oxygen sensors that are located between the catalytic converter and the motor, the "upstream" sensors are the ones that are used to adjust the fuel mix.....and could cause the problems that you are having.
However, it is not that easy......if one of those is "dead".......the computer (PCM) will give you a code saying that the sensor is defective.....and will then ignore the sensor data and use a basic program to keep you running.

The oxygen sensor numbering system is as follows.
HOS11 is in BANK 1, Upstream sensor
HOS21 is in BANK 2, Upstream Sensor

HOS12 is in BANK 1, Downstream Sensor
HOS22 is in BANK 2, Downstream Sensor

Bank 1 is the bank of cylinders that has Cylinder #1

Upstream is before the catalytic converter (used to control the engine)
Downstream is AFTER the catalytic converter (monitors the catalytic converter).

$300 limit or not.....I'm sure that you want to get this thing running at a usable state.
I'm not up on what correct fuel trim values should be, you might try searching to look for a post that has them as I have seen people post them before.

As a side note.....if you get to unplugging any oxygen sensor......use care to make sure that you mark the plugs on the harness.
At least on my '96, it was possible to plug them back into the WRONG plugs.....which will drive you super crazy trying to figure it out.

Cylinder #1 is in the back, passenger side of engine.
REAR bank is bank #1
Front bank is bank #1
This means that your P0174 code is indicating a lean condition for the FRONT bank of cylinders.....bank #2.

If you find that your IMRC is not working.....it is best fastened in the closed position.
It should be in the closed position until you have a high power need at high RPMS
Don't rev the engine to try to get it to open.
If it is closed on BOTH banks, you are fine as far as the issues that you are having.

Are there any other code(s) present?

[wiswind]

To add to what I have posted.......I know that you have already looked for any hose(s) that might be disconnected.
But look again......look at the hose that goes from the breather (rear valve cover on your 2002) to the big flex hose that goes from the throttle body to the air filter box.
That has been known to get knocked loose.
Also verify the vaccum line from the PCV valve to the upper intake manifold....for any cracks, etc.

Before you put the upper intake manifold back into place.....make sure that things are wiped down.....no dirt/grit on the seating surfaces.
Also make sure that the upper intake manifold gaskets are staying in place.
Make sure that the fuel injectors are pressed down into their locations in the lower intake manifold.
NOTE.....the area around each fuel injector is a major catching location for a lot of road grit.
You want to have that cleaned away BEFORE you lift a fuel injector up out of the lower intake manifold.
At this point.....I do not suspect that you have any problem with a fuel injector because that would give you a misfire code on a specific cylinder.
At this point....things are pointing toward some vaccum leak into the intake.
A vaccum leak is any air getting into the engine that does not pass through the MAF that is mounted on the air filter box.
The air that is drawn into the breather to replace the air drawn out through the PCV valve is drawn out through the tube that I mentioned for you to check in the flex hose.......so it has passed through the MAF.
But...any air entering through any of the many vaccum lines is game....as well as many other possibilities....which is what makes tracking this down so difficult.

[12Ounce]

What Wiswind is pointing too is most important. It is easy to assume we know the layout of the engine ... but best to have a moment of truth and get it straight. If you need a diagram ... there is one in the first pages of a Haynes manual.

[2002windstar]

Based upon the layout of my exhaust, my downstream O2 sensors are located in the cats (picture attached from my Haynes, my layout is identical), there are no O2's after either of the cats.

And yes I do want to get the van back to a usable state - it has been a great vehicle over the years.

I replaced all 4 O2 sensors around the 110,000 mile mark, the 2002 O2 sensors are 4 wire connections that can only go on one way, at least on my model.

I double checked all of the vacuum line connection and all are connected properly.

The IMRC are in the closed position, there is one controller for both banks and is electronically controlled only - no vacuum connection.

No codes are present other than ABS codes for the front 2 wheel sensors, which should not affect idle (I'll deal with the ABS after the idle problem is taken care of).

The vacuum line from the PCV is brand new (part of the valve cover repair kit) along with a new PCV.

I cleaned out the plenum, upper intake manifold and lower intake manifold very good prior to re-assembly the 1st time, to my angst I DID NOT clean the EGR ports as shown in the video posted in this forum, I did clean them tonight though but needed to stop due to the time and need to get up for work in the AM.

I don't believe that my injectors are an issue either - the o-rings on both the rail side and engine side were replaced and I did pay particular attention to then when checking for a vacuum leak, I hit each one with both propane and throttle body cleaner and at no time was there any change in the engine.

I also believe that it is acting like a vacuum leak but dang if I can locate it! Anyone here ever do a smoke test for a vacuum leak before? It also looks like something I might try if cleaning the EGR ports hasn't resolved my issue.

And finally thank you for all the input and suggestions - please keep them coming until I get this figured out!!

[12Ounce]

Does your model have "coil-on-plug", or does it have the "ignition pack"? If you have the pack, are you sure of the pack-to-plug cable order?
.
Did you replace the (8) hold-down bolts when you did the intake manifold repair?
.
Have you located the timing markings on the harmonic balancer? .... Have you confirmed the timing marks are correct by comparing them to a plastic "feeler rod" dropped into the #1 cylinder? (On high mileage engines, it is possible for the rubber element on a harmonic balancer to go soft, allowing the toothed ring to get out-of-sync with the crankshaft ... then the ignition timing is incorrect. I just replaced the balancer on an old Tracer ... that had slipped 30 degrees or more.)

[2002windstar]

Originally Posted by 12Ounce

Does your model have "coil-on-plug", or does it have the "ignition pack"? If you have the pack, are you sure of the pack-to-plug cable order?

I have the ignition pack, I made the mistake once of getting the plug order wrong so pay close attention anytime I remove any wire from it, but never hurts to triple check
.
Did you replace the (8) hold-down bolts when you did the intake manifold repair?

Yep with green grommets, VICTOR REINZ has a complete kit with all of the gaskets associated with the manifold (upper/lower/plenum, IAC, throttle body, EGR, aluminized RTV sealant and the new mounting bolts.
.
Have you located the timing markings on the harmonic balancer? .... Have you confirmed the timing marks are correct by comparing them to a plastic "feeler rod" dropped into the #1 cylinder? (On high mileage engines, it is possible for the rubber element on a harmonic balancer to go soft, allowing the toothed ring to get out-of-sync with the crankshaft ... then the ignition timing is incorrect. I just replaced the balancer on an old Tracer ... that had slipped 30 degrees or more.)

No I have done this but will add it to my check list of items to verify, compression testing is also on that list as well.

I have my fingers crossed that when I put the plenum back on tonight that cleaning the EGR ports did the trick - but I never seem to be that lucky.

Thanks for the suggestions and I'll update later.

[scubacat]

When I first did this, one of the wires somehow slipped off the coil pack. Be sure to make sure they're all securely fastened (around your waist. In the event of a water landing... never mind...)

Also, you might want to remove the coil pack and look at the back side of it. If you see any cracks (even a tiny one), you'll get arcing and will need to replace the coil pack. That's unfortunately a routine failure item for these vans. (I'm on my second one currently.)

[12Ounce]

And BTW, have you even taken a test drive with the vacuum hose removed, and plugged, that powers the EGR valve? Just to see if removing the EGR from the combustion will eliminate the bad engine performance?
.
(Of course, this will also cause additional temp codes>)

[2002windstar]

Update time - after a couple of days of teens to below zero temps in our area I finally caught a weather break - it was in the low 30' today and felt like a heat wave!

Anyway I was able to look at several potential issues.

Removed the plenum to clean the EGR ports - they actually looked fairly clean, so I must have at least hit them with throttle body cleaner when it was off for the gasket change. I did take a coat hanger wire and put it through each port - just in case there was blockage but at this point it doesn't appear to be the issue.

I triple checked the vacuum hoses and connection to the upper intake manifold, all appear in good condition and were/are properly connected.

I pulled the plug wires off of the ignition pack and removed the pack to inspect it for cracks. There are no cracks on the body or in the underside in the epoxy.

So I decided to pull the plugs and inspect them, on each bank I had at least one on each bank that had ash accumulate on it to the point of the ash contacting the electrode, I had some that appeared "normal" and some that had slight carbon deposits. The plugs are Bosch Platinum Fusion plugs.

At his point I believe it is the plugs, they were replaced 67k miles ago along with the coil pack.

I order wires and plugs from RockAuto which should be here maybe Saturday. After installing these hopefully the issue will be gone. If not the next step will be to remove the vacuum from the EGR, plug it and take it for a ride.

Thanks for the suggestions and I will update upon installation of the plugs and wires.