'97 Chrysler Concorde appreciate help (long)

[gkcooper]

Guys, here's a baffling story that I need help with. I never enjoy being stumped, especially by a car. This car has the 3.5 V6 which, until recently I had zero experience with any real maintenance. Last December, I paid the local Toyota service department $650 for manifold gaskets, water pump, valve cover gaskets, belts, timing belt. It was the first time in ten years that I have paid anyone to work on a vehicle that I own.

That's where my problems started. Why did I go to Bill Penney Toyota in Huntsville? Well, my wife worked there as an accountant and they said we could get a real good deal :)

The car seemed to run OK after they worked on it except for a high idle.

These guys are real hacks.

The car went on a family vacation last June. It was driven about 800 miles. On the way home a CEL and a stumble was noticed.

I checked the fault codes a few days later and had a P0303. This indicated a cylinder misfire on #3.

I then decided to replace the plug wires and plugs.

The CEL and stumble was still there.

I decided to remove the upper intake plenum and replace the gaskets even though they were just done (supposedly).

To my amazement the old gaskets were REUSED! I decided to pull the lower manifold and replace all the gaskets. Upon doing so, I discovered that the fuel rail was leaking. OK, this is starting to be a real chore.

After removing the manilfolds, fuel rails, throttle bodies, etc. I discovered a hairline crack in the fuel rail. The fuel rail recall had already been performed, so I just went to the junkyard and obtained another fuel rail. I purchased a fuel rail recall kit from the dealer and replaced all the O-rings.

When I put everything back together it ran absolutely beautifully with the exception of a few extra miliseconds of extra cranking time required.

My wife drove the car a few days and then complained about the hard starting and missing.

I test drove the car and decided that I would go ahead and change the AIS motor, even though I had thouroughly cleaned everything before re-assembling it. It made no difference in the starting.

Now, if you attempt to go WOT, the car stumbles totally. It will not exceed 3k rpm at WOT. There are no fault codes.

I have checked the fuel pressure and the cam timing and they both seem (to me) to be fine.

I would really appreciate any input or help on this.

Greg K. Cooper
Huntsville, Alabama

[shadow88]

I'll take a stab at it. This is assuming no codes or fuel leaks, or any silly stuff like ingition wires in the wrong position.

I'd start by looking at the coil pack for corrosion. I've seen a few of these rust the terminals that the wires go on. Clean and use dielectric grease if any problems found.

I'd hook up a vacuum gague to see manifold pressure. 19 ish should be what you find. Causes of low vacuum are cam timing, bad ignition, bad egr, restriced exhaust. I know, there's more than just those, but those are the common LH problem areas.

Then I'd move to the egr tubes that go into the upper plenum. I'd make some block-off plates from pop or beer cans and slide them between the tube and plenum to block off a potentaily stuck open egr. Road test, and if it's working properly, then you need and egr assembly.

But if you have any codes, obvously start with them first. I've seen cam sensors not fail often enough to set a code, but it will cause the symptoms you have described.

My brain works faster than my hands can type, so sorry about the order this was typed out. Post back your findings.

[gkcooper]

It was the cam position sensor.