I bought this thing 2 months ago today and it ran fine when I test drove it. No cel or missing, it idled and ran pretty smooth. The guy said he had just replaced the ignition coil, and it looks brand new too. After a day or two, it started running pretty bad. Missing all the time, particularly under load. I hooked up my reader and got 5 codes. I can't remember them all, but I'm pretty sure they were lean both sides, a misfire in 1 cylinder, iac fault, and tps fault. I did a brake cleaner intake check and found that all the gaskets were bad. I replaced them, but not the grommets, and got the lean codes again. Replaced the grommets and didn't get another code for a month, but the car still runs bad. I swapped the plugs, well all but the back passenger side, I just can't reach it yet. Finally got a cam position sensor fault code, so I replaced it. This thing still runs like crap. It has been missing badly at startup lately, and it's been pretty cold. It misses with little impact all the time, and misses badly when accelerating up a hill or right when it switches gears around 30-40mph. the whole car bucks and chugs at both times. It also mysteriously eases up sometimes and runs a little better, but not completely better. I thought it was temp. related, but it switches back and forth from starting up good and running worse as you drive it, to starting badly, but getting better as you drive it. I've also run a whole bottle of sea foam through the injectors, plus a couple other injector cleaners, and I changed the oil and fuel filter. I've only gotten the cam pos. fault code since I fixed the gaskets, but this is our only vehicle with 4 kids and a very tight budget. I don't know where to start and it's too cold to be out in the snow trying to check everything under the hood. Anybody have any ideas about what to try next? Any help will be greatly appreciated, thanks!

 

James, as you know, that last plug is probably the cause of the misfire because you can't get to it . Persistence pays , and you don't want to keep driving it too long with a misfire because it can destroy the catalytic converter, and they can cause low power problems and very poor performance. They are not cheap either.

 

I know the plug is probably part of the problem. The thing I'm trying to figure out is the rest of the problem. If the miss was only because of the plugs, it would've gotten better when I changed the rest of the plugs. I intend to replace the last one as soon as it warms up enough to fiddle with it for a while unless someone has a trick to get to it. Ive spent 4 hours trying to figure out how to get it with no success. How can I tell if the cat is messed up? Would it cause the miss? Its not just one cylinder missing.

 

If you have been driving for a while with the misfire problem it could affect the converter, however, the check engine lite will flash on and off if there is a serious current emission problem.
How do you know there is more than one cylinder misfiring?
If you are getting a check engine lite, have the codes read at one of the auto supply stores like Autozone. They do it at no charge to the customer. If there any codes get the numbers and post them here if you require further assistance. There is plenty of help available and some pretty knowledgable folks here.

 

James, you couldn't be in better hands than hanky's. To get to the rear plugs you need to take off the wiper arms, the plastic cowl and the metal cowl with the wiper motor.

Make sure you have all vacuum lines attached to the intake manifold. It is easy to forget the one on the passenger side to the rear.

You replaced the grommets and other seals. You should be good there.

These 3.8 engines also have intake manifold runners and a control system. Yours should be electrical. There are 4 tiny white plastic grommets on the actuator arms. They brake and get lost. They will cause a slight idle roughness, nothing like you describe. But it is worth checking.

I am bringing these things up because they are cheap to do: Clean the MAF sensor with a MAF sensor cleaner.
Clean all ground contacts on the engine and the body. Make sure all ground straps are there.
Use some other method to look for vacuum leaks. You could blow cigar smoke into the brake booster hose. But keep in mind that Ford allows for vacuum leaks around the intake manifold runners and compensates by computer for the extra air.

Another trouble spot at higher mileage Windstars is the cam synchronizer.

Once you have replaced the last spark plug and if there is still a problem get a fuel pressure reading as well.

 

There is a problem with the check engine light, either the bulb is blown or it's shorted out somehow, but it doesn't light up at startup like it should. I have cleaned the maf with specific cleaner, and I also have a code reader and the Haynes manual with the code definitions. I check the codes all the time, but don't get the flashing cel because its broke. I will try the cowl removal to double check those vacuum lines and swap the last plug hopefully Thursday. I started to remove it once before to get a better look back there, but stopped before the metal one because I wasn't sure if it came off any further. I'll go again and find out how it comes off. I don't think I missed any last time, but better safe than sorry. I will also take a look at those actuator bushings, I know the ones you are talking about.

I do have a couple more questions, though. Are there a lot of ground straps on this thing? I haven't done much into car wiring yet, but I do have a rudimentary knowledge of wiring in general. Is there a way to know a number of straps I need to check, so I don't overlook any? I have the Haynes with the wiring diagrams, but its all a bit overwhelming with all the lines and symbols. I guess what I'm looking for in this one is, is there a number and/ or diagram of the ground straps? I know of at least 2. The one from the battery negative, and I found one on an exhaust hanger near the gas tank. The battery contacts look good, too. There is one anomaly in the electrical I forgot to mention. One of the previous owners cut the hot wire to the small a/c fan on the radiator and ran a switch to it. I've done this on other cars to the main fan, but I didn't cut the wire, I usually cut the insulation and added the switch wire into the mix. I have no idea why this was done because the main fan comes on correctly. Maybe the a/c fan doesn't come on with the a/c and the tried to fix it? I don't know. I haven't been able to get into that one, but I have wondered if it may be part of my other problems...

Thanks again for the assist. I really want to get this thing running and I'm having a hard time alone. Fuel injection is a foreign language to all of my friends who know cars except 1, and he only really knows jeeps.... Thanks!

 

I forgot to mention how I know more than one cylinder is misfiring. The answer is, I don't, but the miss is very erratic and seems to me like it misses more than once per rotation, which makes me think maybe more than one isn't firing. Plus, in other cars I've had that were missing due to the plugs, the miss got better as you replace the plugs. I've had a few minivans that were hard to get to the back plugs on and had to drive it between times with a noticeable improvement. There was absolutely no improvement to this thing after 5 of 6 replaced. I know that one isn't firing right, .095 gap on the other 2 in the back, but I felt there should have been some improvement to the miss when the others got swapped if the plugs were the main problem...

 

James,
If you place your hand at the end of the tailpipe with the engine idling, you will feel a regular popping from 1 misfiring cyl. If you feel a double popping then you have more than 1 cyl misfiring. There could be a coil not working properly.
It is very important to check that bulb for the check engine light and if defective , replace it. It is a form of yours eyes on the engine and should be there for you to watch what is going on. It is usually a #194 bulb the same as all the dash light bulbs. Fuel injection is not as complicated as the older carburetors were so don't be afraid to learn about it and the more you learn the easier it is to understand what is going on.
If you open the dash and don't find a bulb that has turned black , possibly the bulb was removed because the light was always on. In either case try to get it working.

 

Some one dealt with a harmonic balancer that deteriorated so that the timing tone wheel for the crank position sensor was off by various degrees. You can see the tone wheel on from below on the passenger side. I suppose you could try to move it while the engine is still. I suppose it should have a little elasticity but it should "give".

Sorry I can't find the thread right now.

 

I'm not sure I understand what you say I should check with the crank sensor thing. Is it supposed to move? should it move in a particular direction? I'll check the Haynes for some more detail when I look for the cam synchronizer? you mentioned before also.