Need Help With 99 WIndstar Check Engine Light ...codes p171 & p174...

The codes I got say running lean on bank 1 and bank 2....guy at parts source thinks its a vacuum leak. I took it to a buddy (backyard mechanic ) but very good at detecting these things Im told, he cant find a vacuum leak but he thinks its the intake manifold gasket....
any suggestions?
this is about a $400.00 job Canadian funds....the dealer is about double that Im told...
not sure what else it could be...he said the egr was working fine he tested it with a vacuum pump..did a few tests etc...
thanks for any input...
Dave

Do a search on this forum. There are endless amounts of threads on this issue and very likely your problem is the Isolator bolt deteriorization that causes an intake leak around the port seals.

If you do searchs here, you will find that many of us have had the same problem. Your mechanic buddy is close.... manifold gaskets .... and in particular, "isolator bolts" ... which are part of the gasket/seal scheme for the upper intake manifold. The isolator bolts have built-in seals that seal the manifold "spacer" to the lower metal manifold.

I had the same thing on my 99. I have since cleaned the Mass Air Flow sensor in the aircleaner with brake cleaner and also replaced the left valve cover & pvc as indicated in the TSB listed below. It's been over a month with 800+ miles and no return of the codes. But still have a constant pinging problem.

The information on the following page has great detail on the TSB that was issued for this problem.
http://leckemby.net/windstar/windstar01.html

Thank you all for the help...
Dave

so you didnt replace the gasket set or isolator bolts?
thanks for any other tips..
Dave
I had the same thing on my 99. I have since cleaned the Mass Air Flow sensor in the aircleaner with brake cleaner and also replaced the left valve cover & pvc as indicated in the TSB listed below. It's been over a month with 800+ miles and no return of the codes. But still have a constant pinging problem.

The information on the following page has great detail on the TSB that was issued for this problem.
http://leckemby.net/windstar/windstar01.html

If grnf did not replace the bolts and seals my guess is that by cleaning the MAF it is now reading more accurately. Of course no more air is entering but the reading from the MAF is indicating that more is and a slight increase in fuel is calculated and delivered. Perhaps his seals are just starting to leak but not enough to register an error with the cleaned MAF. (but it did with the dirtyMAF) My guess is that he simply bought himself some time. I hope this is not the case for his sake.

what is a DPFE ? what does that mean if I order the part?
thanks

DPFE = Differential Pressure FEedback sensor. It monitors the EGR system flow rate.

The DPFE is another common failure for the 99s and perhaps a few other years. It gives a different code or two. (401???) When you get this failure it is about a $70 part and 15 minutes to repalce so not a huge deal.

so you didnt replace the gasket set or isolator bolts?
thanks for any other tips..
Dave


Sorry for not getting back sooner .
Not yet on the isolator bolts or gasket. But I'm thinking I will end up doing it since it is still pinging.

Sorry for not getting back sooner .
Not yet on the isolator bolts or gasket. But I'm thinking I will end up doing it since it is still pinging.
No guarantee that the isolator bolts will stop the pinging. I had the complete TSB done plus fuel injectors cleaned and tune-up. Still pinging it drives me nuts. Tried mid grade and high grade gas just a slight difference from using regular grade. Adding a gas additive has helped some. Also, having power issues sometimes it is gutless sometimes it is normal. PCM has been reprogrammed. ON top of that gas mileage stinks! Right after the TSB service my van had a definite power improvement and the pinging was gone but that last only a few weeks. No CEL. I hope it fixes your ping problem just wanted to tell you me experience.

You might think about trying the Seafoam treatment discussed in another thread. It might remove enough carbon deposits to reduce the pinging.

You might think about trying the Seafoam treatment discussed in another thread. It might remove enough carbon deposits to reduce the pinging.
I am going to expose my lack of knowledge of cars here, but where would there be carbon deposits? In the lower intake manifold? If so we had a new intake manifold put on at the time of the TSB this past August. I am probably totally confused on (acutally most likely) how all these things come together.

Carbon deposits inside the cylinder. This would effectively DECREASE the chamber size (in the head) and thus compression would increase. This could cause pre0ignition otherwise known as pinging.


Unless of course Lewis is refering to something else.

Are you getting a flashing CEL? indicating a misfire? This could be mis-described as pinging too.

Carbon deposits inside the cylinder. This would effectively increase the chamber size (in the head) and thus compression would increase too. This could cause pre0ignition otherwise known as pinging.

Exactly. The TSB issue is a result of significant oil pickup into the intake which eventually loosens the isolator bolts and leads to an air leak. At the same time this oil is building up carbon deposits in the cylinders leading to pinging and the need for the PCM reprogram. The PCM reprogram presumably retards timing in certain situations to limit pinging which will result in reduced performance and MPG. But it does not address the actual cause of the problem which is the carbon deposit buildup in the cylinders. Seafoam or other cylinder treatments might reduce those deposits enough to help with the pinging problem.

Carbon deposits inside the cylinder. This would effectively increase the chamber size (in the head) and thus compression would increase too. This could cause pre0ignition otherwise known as pinging.


Unless of course Lewis is refering to something else.

Are you getting a flashing CEL? indicating a misfire? This could be mis-described as pinging too.

.. okay I understand. It will be worth trying the Seafoam than. I don't have any lights on at all. CEL hasn't come back on since having the TSB done.

Exactly. The TSB issue is a result of significant oil pickup into the intake which eventually loosens the isolator bolts and leads to an air leak. At the same time this oil is building up carbon deposits in the cylinders leading to pinging and the need for the PCM reprogram. The PCM reprogram presumably retards timing in certain situations to limit pinging which will result in reduced performance and MPG. But it does not address the actual cause of the problem which is the carbon deposit buildup in the cylinders. Seafoam or other cylinder treatments might reduce those deposits enough to help with the pinging problem.


Except that I should have written that it causes the chamber size to decrease and not to increase.

I will correct my original post.

Goldlexus let me know how well the Seafoam works. I have not seen it in Canada yet but if it works I would consider taking a drive (I only live 90 minutes from the border) to use it as preventive maintenance. If anyone has seen it in Canada please let me know where.

The codes I got say running lean on bank 1 and bank 2....guy at parts source thinks its a vacuum leak. I took it to a buddy (backyard mechanic ) but very good at detecting these things Im told, he cant find a vacuum leak but he thinks its the intake manifold gasket....
any suggestions?
this is about a $400.00 job Canadian funds....the dealer is about double that Im told...
not sure what else it could be...he said the egr was working fine he tested it with a vacuum pump..did a few tests etc...
thanks for any input...
Dave

Did replaced the lower gasket total of 6 and the insulator bolts 8 total 4 weeks ago and the code still not back, Normally it takes 3 days then the code is back. Open this web page and just follow just like i did. http://leckemby.net/windstar/windstar01.html.
The parts itself cost me almost $100.00. Good Luck.

Thanks I did that work already, I replaced the Isolator bolts (8), the 6 port seal gaskets and the top halve seal gasket (1 big one)
what I am worried about is maybe I should have replaced the valve cover also....I think mine does have the hole now I took a picture of it and the flash got in there its hard to see ...
just dont want the other work to be a waste of time but the valve cover here in Canada is over $100.00 itself....
thanks again
Dave
Did replaced the lower gasket total of 6 and the insulator bolts 8 total 4 weeks ago and the code still not back, Normally it takes 3 days then the code is back. Open this web page and just follow just like i did. http://leckemby.net/windstar/windstar01.html.
The parts itself cost me almost $100.00. Good Luck.