...sudden loss of power and violent hesitation?

Cause thats what happened to me while driving, and I'm trying to see if its something else besides a blown motor. I have spark, and I think I have fuel. How do I test the ECU?

1991 n/a

 

At what RPM is the hesitation? Have you searched for "hesitation"? Lots of info.

There's no easy way to "test" the ECU.

 

Well you can test ALL of the ECU inputs and outputs... (good 1.5 hour activity there... ) ...dunno if this is an adequate "test" of the ECU though... Aaron?

(Other than the time it takes to do, its a fairly easy procedure.. )

 

Aaron, I am almost sure its a blown apex seal. But i want to get a consensus since I cant get a real compression test done.

I was driving on the hyw. slowed down for offramp, on offramp it began suddenly to violently shake and lost a ton of power. As I pulled off the ramp, it died and would not start again.

I tested spark and thats good. I just find it curious that if its a blown motor...there are no error codes on the ECU - thats why I asked here.
Thanks

 

it would be easier to check the compression, unless you get code 14 (the replace ecu code) then the ecu is almost the last part in the diagnostic "chain"

mike

 

i had the same exact problem reset the ecu and now it runs fine if you figure out why it happened please let me know

 

Sounds like limp mode. Pull the cel codes before you waste your time elsewhere.

I changed my fuel filter, replaced my fuel pump sock and swapped my fuel pump, verified my injector spray patterns before I checked the codes. Wasted time and money. Check the codes first. If it is MOP codes, there is a pretty good chance that the output section of your ECU is fried. DO NOT swap in a new ECU until you have thoroughly verified the new MOP. Look at this thread- https://www.rx7club.com/showthread.p...light=mop+test

Check the codes first. FSM for the procedure.


Good Luck.

 

How did you "reset" the ECU?

 

Probably just pulled the power.

For some reason people seem to think that the FC ECU can be "reset" like a modern ECU. No idea where this came from...