98 Windstar P0304 Other Problem?

[wiswind]

You will NOT have vaccum to the EGR valve at idle.....It will open only when driving. I am not sure of all the inputs that the PCM uses to determine when and how much EGR flow to command....but the vaccum is regulated by the PCM signal to the EGR vaccum regulator solonoid.....which is mounted to the back of the upper intake manifold. The source of the vaccum to the EGR vaccum regulator solonoid is a line that connects to the same vaccum line that goes to the PCV valve.....which enters the upper intake manifold at the top....right next to the throttle body and IAC (Idle Air Control).

Your 1998 windstar has a different....and much more reliable upper intake manifold than what is found on the '99 and newer years. So you are not going to have the isolator bolt issues....the TSB for the P0170 /174 codes.

The DPFE is a common failure item....and easily replaced.

I have not been through the head gasket / lower intake manifold gasket issues.....with my '96.
From what I have read.....you DO NEED to change your oil....PRONTO!!! The reason is....if any coolant got into the engine oil....it will take out the bearings in the engine......

On my '96, the fuel pressure check point is, I think, the same place that you released the pressure.....The center of the front fuel rail. Just like a tire valve. I don't know off the top of my head what the correct pressure should be.....and if it is the same for the '98.

Oh....also very worth doing....as you have them out..... Check the ends of the fuel injectors...the spray end. It is normal for crud to build up inside the plastic cup that is over the end of the fuel injector. Spray some carb. cleaner into there...and flush it out. I had a P0301 code.....that ended up being caused by just that. They were all dirty, even after several runs fo fuel system cleaner.

[12Ounce]

There are gauge and hose testing kits available for testing the fuel rail. I have one, but just using the "shop rag around small allen wrench" method on Schraeder valve is what I usually do. ...while the key is "off", of course. The rag should get wet..but if gas "spews", indicating intrained air, there may be pump issures. I'm guessing you don't have a fuel pressure problem... but keep it in mind.

The control line to the EGR valve comes from a vacuum regulator/solenoid control valve mounted ont the firewall (on my model). At idle, you should feel almost no vacuum on this hose.. not enough to open the EGR valve. Also check the lines at the DPFEgr sensor mounted on front of engine...more apt to be crudded up.

[Ulsterman]

Thanks so much for the replies and info 12Ounce and Wiswind.

12Ounce
I too doubt very much if fuel pressure is contributing to the problem. I looked at the lines to the dpfe and they were pretty clean but I intend to change this sensor as its known to give problems but right now my priority is to cure the engine 'knocking' at startup and then to irradicate the fault codes. This weekend I intend to try your 'remove the spark plugs' test. Meanwhile I'm investigating head gasket sets and change procedures.
By the way your reply is listed at 5.20am? insomnia? I'm on my way to work at that time but I sincerely hope my windstar's problems aren't causing you to lose sleep?

wiswind
I think I would have preferred to get the plastic plenum apart for cleaning when I did the lower intake manifold job recently - I was just able to shake some solvent around inside it but I agree it does seem to cause less problems than the later models.
I fully intend to change the oil but the vehicle is not being driven right not until I can cure the knocking at startup which 12Ounce and I suspect is caused by coolant getting into the combustion chamber/s. I even bought some heavier oil as suggested by 12Ounce. I fear that I will end up changing head gaskets soon and the oil will be changed at that time with no driving in between.
As said above I believe that the fuel pressure is ok and I intend to change the dpfe anyway.

[Ulsterman]

wiswind - I cleaned the injectors when i had the lower intake manifold off and sprayed throttle body cleaner inside as you suggest

[12Ounce]

No, no ... just too much beer and bad kidneys. LOL.

[wiswind]

I have the vaccum solonoid for the "Evaporative Canistor Purge Valve" mounted on the firewall.....Which also gets its' vaccum from the same place that the EGR Vaccum Regulator sololoid does......

[Ulsterman]

Well I'm not really any further on.
First I tried 12Ounce's recommended removal of all the sparkplugs and cranking the engine - couldn't detect anything being ejected from the cylinders at all and I wiped each plug opening afterwards to check. I replaced the plugs and the engine started with the same knocking noise though it didn't seem as loud (which disappeared once normal operating temp was reached) and the cooling fans cycling on and off - the cel came back on with the same P1401 code.
Next I tried to follow one posters test for a failed head gasket by driving the van to Autozone (30 mile round trip) and borrowing their cooling system pressure tester. The first test told me that the radiator cap was faulty which I replaced but the guys at Autozone were unable to find a suitable sized adaptor to connect the tester to the radiator neck to allow me to pressure test the windstar's cooling system. Bit of a wasted trip however it does look like the engine has ceased losing coolant though so some good news.
Rest of the weekend I went up to my wife's parents place and 'resurrected' her old 93 Ford Festiva and got it running so at least she's no longer grounded while I'm at work - at 140,000 miles the little Festiva still runs fine having seen nothing more than routine maintenance since new. Oh and I did my taxes intending to finance the windstar repairs with the refund.
My next plan for the windstar is to replace the DPFE sensor and make sure all the vacuum lines are clear but I'm beat after that. Any ideas or words of wisdom appreciated guys!

[12Ounce]

Well, thats good news! No coolant in combustion chamber!

I had not noticed that your code had changed from P0304. Change that DPFE sensor and I bet you're home free.

[Ulsterman]

Originally Posted by 12Ounce

Well, thats good news! No coolant in combustion chamber!

I had not noticed that your code had changed from P0304. Change that DPFE sensor and I bet you're home free.

Here's hoping you're right my friend - Thanks once again!

[wiswind]

Right now...I get a very anoying noise....more of a rattle.....and have tracked it down to the insides being loose in the rear-most catalytic converter.
I have put the large "hose" clamps onto each converter heat shield as the FORD TSB says to....but when I thumped on the rear converter....I could still hear the rattle. If you have loose heat shields (would be caused by a broken weld joint), go to the PLUMBING department to get the large hose clamps..... and install one over each weld point on the converter....(2 per conveter).

Your DPFE sensor change is an easy DIY item....and you can buy one at many auto parts stores.

[Ulsterman]

My wife is picking up one of the sensors for me today so i'll fit it this evening when I get home from work and let you guys know. 12Ounce was for betting so the odds must be good!
As for the cats I'll take your advice wiswind and put the clamps on my to-do list.

[Ulsterman]

Well 12Ounce right once again!
I changed the DPFE sensor yesterday evening and the van started up sweet from cold - engine noise gone completely. I've now driven it about 50 miles and so far no check engine light so it's looking good. I'll drive it to work today and tomorrow and watch the coolant level closely. If all goes well I'll flush the coolant at the weekend and change the oil. By the way I bought some castrol 5/50 synthetic to change to a heavier oil after the egr port cleaning / manifold gasket job as you suggested in another thread.
I'm just curious to know what was making that knocking noise from the engine - like a cam / valvetrain component or a bearing gone bad but disappearing once normal operating temperature was reached?
Thanks again for you help.

[12Ounce]

If you were working on a '99, I would suggest the noise might be the "loose" inner piece in the upper manifold... the one I like to secure with RTV to help dampen vibrations.
But the '98 probably has a totally different upper manifold design.

So I don't have a clue!

[Ulsterman]

Well the noise shall remain a mystery but it was a worrying mechanical knock. At the weekend I put everything fully back together, flushed the coolant and changed the oil and filter. All's well that ends well so they say.