Chugging / Missing Disco 98 at cold-start

[Pedro_malo]

Hey Guys-

I believe I am losing my mind with this problem. Please even really crazy ideas accepted.


This problem has been going on for months and I'm running out of patience and mechanics in area. So far 2 mechanics have given up on problem as unsolvable. Any ideas would be very much appreciated!

Vehicle: Disco I, 75Kmiles.

Problem: Each morning (especially when extra humid outside) the Disco starts fine but chugs and sputters like mad, until it gets to up to temp and then clear within 5 minutes. The vehicle is undrivable until problem clears. The TAC fluctuates dramatically from 0-1.5k during this time. The problem ALWAYS clears itself. The Disco sounds like it is running on 1 cylinder or being flooded with too much gas.

I have replaced the following:

Cam Shaft sensor, Timing Chain, Stepper Motor, Coil Pack, Crank shaft sensor, new plugs and new wires x2 (Magcore plug wires)

I have swapped out/ tested with known good the following parts:

MAF, ECU, CATS.

The latest change was new stepper motor and new coil pack, but the problem remains. Ideas? The Disco also "seems" to be dripping excessive water from AC unit, but that may unrelated. No codes other than Misfires / Possible damage to CATS. Once problem clears DISCO runs fine until cold-start the next AM. Also- I only put < 10 miles each day on my truck.

Hypothesis:

I'm starting to think that somehow excess water is building up or collecting as vehicle cools down which affects the vehicle and starting in the AM.

I even sent a note to the "click and clack guys" - they didn't bite.




Thanks!

Peter

[Adam in NYC USA]

You sound like you have the same problem with the fuel temp sensor on the fuel rail except it happens when it is cold. Most D1s have that when the engine is hot.

The resistor or the wire opens when cold and then connects and works normally. Inspect that first and see if you can borrow a codereader to read the ECU for more hints.