Any shade tree mechanics that can diagnose this one?

**River_Rat_459** · 05-10-2011, 16:40

I'm having a hell of a time figuring this one out. Has anyone had something similar happen with their car?

I have a 2000 Ford Taurus with the following:

24V V-6 DOHC, 3.0 L Duratec engine
134,000+ miles
Pretty well kept up on maintenance

Though the body is a little worse for wear, the engine and chassis are in good shape. I just put in a new set of spark plugs about 8,000 miles ago, so I think that can be ruled out. At any rate, here's the issue...

When the car has been sitting for a long enough for the engine to cool down completely (i.e. over three or four hours), it runs very badly the next time it is started. It misfires, knocks, stumbles, dies, etc. I can usually drive about three or more miles, and then it goes away until after the engine has cooled down. At that point, it starts up again.

I cannot find any vacuum leaks, and even if I did I believe the problem would be more consistent as a result. I ran an OBD II scan and get P0174 and P0171 routinely, which means that the fuel system is too lean. There are a few common problems listed at this site. Some forums have also listed possible problems such as EGR valves and oxygen sensors. I had the fuel injectors professionally cleaned out a couple of years ago.

I also ruled out water in the tank, as I ran the tank to nearly empty then used a couple of bottles of water removal (HEET), then filled the tank with fresh, higher octane gasoline.

As I mentioned, the problem is not consistent. It only seems to happen after the engine has fully cooled. If the morning is cooler (i.e. below 50 degrees Fahrenheit), it takes longer for the engine to settle down. The last few mornings, when the temperature was up over 60 degrees, the problem was still there, but didn't take as long to overcome...I only had to drive about two miles before it fixed itself.

I'm thinking of putting the focus on towards the mass airflow sensor first, since it seems to be the easiest thing to replace at the moment. I'm not sure beyond that, since there seems to be so many different things that can be wrong.

Has anyone else had anything similar happen with their car? Any advice (aside from the obvious "buy a new car"

) would be appreciated. Thanks!

**ladym123** · 05-10-2011, 17:39

If you tried everything else then yeah the MAF or oxygen sensors....the oxygen sensors are cheaper though right? Try ebay

**Ironhide400** · 05-10-2011, 17:40

Well, my Mom did have a very similar issue with her mini coop. Obviously a totally different car, but similar behavior. Apparently mini coop is having problems with their cars here in the US where we have drastic temp changes during the course of the day (so the dealer said). Anyway, what is happening is the upper intake/MAF is getting condensation in it once it cools down causing the issue. Once the engine warms up and evaps the condensation, the car runs fine. It was horrible this spring with the drastic temp changes and humidity. They actually replaced both parts, but they said BMW is still working on a complete fix. Something about changing the design of the MAF to better accommodate the temp changes.

Maybe this will give you some direction? If not, then it is a heads up for any mini coop owners here...lol!

**jxspyder** · 05-10-2011, 17:40

Buy a newer used car?

Sent from my DROIDX using Tapatalk

Guest · 05-10-2011, 20:37

Originally Posted by Ironhide400

Well, my Mom did have a very similar issue with her mini coop. Obviously a totally different car, but similar behavior. Apparently mini coop is having problems with their cars here in the US where we have drastic temp changes during the course of the day (so the dealer said). Anyway, what is happening is the upper intake/MAF is getting condensation in it once it cools down causing the issue. Once the engine warms up and evaps the condensation, the car runs fine. It was horrible this spring with the drastic temp changes and humidity. They actually replaced both parts, but they said BMW is still working on a complete fix. Something about changing the design of the MAF to better accommodate the temp changes.

Maybe this will give you some direction? If not, then it is a heads up for any mini coop owners here...lol!

This sounds logical to me... Fords are prone to this. I will ask my buddy 2morrow he is very intellgent when it comes to vehicles...Especially Ford's.

**djwhy60** · 05-11-2011, 05:25

From what I have read it sounds like a vacuum issue. I would check all the vacuum lines while I was digging around. The EGR seems to have probs in these cars.

Guest · 05-11-2011, 20:57

Originally Posted by A-25TH-ID-VET

This sounds logical to me... Fords are prone to this. I will ask my buddy 2morrow he is very intellgent when it comes to vehicles...Especially Ford's.

Hopefully my Buddy got you squared away with this.

**MARDIGRA21** · 05-11-2011, 22:07

Vacuum lines, maf or fuel pump. I had a similar problem with my wife's explorer replaced the maf sensor, problem solved

**River_Rat_459** · 06-02-2011, 15:32

Originally Posted by jxspyder

Buy a newer used car?

Sent from my DROIDX using Tapatalk

I wound up taking Spyder's advice. I just bought a 2003 Chevy Trailblazer EXT. It's a little high mileage, but it runs like a champ has been well taken care of. I was able to get a halfway decent trade-in for the Taurus which was surprising, considering the huge dent in the front quarter panel (from a deer collision). I took it home for less than the price they had it on special for. I'm thinking of it as my Army retirement / college graduation gift for myself...LOL.

The A/C needs charged, but I think I got a good deal in the end. This is the picture of it from the dealer's website.

DC174F09-B763-4403-8247-8935865CB663_1.jpg

Guest · 06-02-2011, 17:42

Originally Posted by River_Rat_459

I wound up taking Spyder's advice. I just bought a 2003 Chevy Trailblazer EXT. It's a little high mileage, but it runs like a champ has been well taken care of. I was able to get a halfway decent trade-in for the Taurus which was surprising, considering the huge dent in the front quarter panel (from a deer collision). I took it home for less than the price they had it on special for. I'm thinking of it as my Army retirement / college graduation gift for myself...LOL.

The A/C needs charged, but I think I got a good deal in the end. This is the picture of it from the dealer's website.

DC174F09-B763-4403-8247-8935865CB663_1.jpg

Nice!!! I just wished I could have the $$$ to get a Tranny in my truck. I am kinda of sick of driving my Moms little Ranger around.