Perplexed

[E. Roy Wendell IV]

> Robert Myers wrote:
>> How did the car do?  A: Flawlessly.  Now the question is "Why?"  I
>> did two things to the car two days before we left.  1.  Pull, clean,
>> coat w/ Stabilant 22a, and replace the MAF connector.  A test drive
>> still gave a cut-out.  2.  Gave the same treatment to the engine
>> speed sensor connector.  Test drive still gave a cut-out.
>
> Wild guess... Water in a connection somewhere that the heat in
> the engine bay, over hundreds of miles, managed to evaporate.
> Dry connection, no more miss.
>
> But that doesn't mean the miss won't come back.
>

 From my experience so far, the only time I have encountered this  
type of problem where no code was stored it was the ECU itself at  
fault. After all, the ECU can't diagnose itself. Being as you've  
already swapped the ECU and the problem still appears I'm thinking  
it's a problem with the power or ground circuit for the entire EFI  
system. The ECU can't store a code if during the time the fault  
occurs the ECU is powered down.

Main engine to chassis ground? Some sort of EFI relay, perhaps  
related to anti-theft system? Ignition switch (bet you've already  
replaced it but I don't remember)?

Roy Wendell
erwendell at mac.com
Too many type 44 tq
A pair of MR2s