1993 FD (rhd)
Stock rebuild
Factory ECU
Stock Injectors
Brand new plugs
Removed secondary throttle plates
All new vac lines

So finnaly got the motor in the car up and running. The car starts, runs and idle's fine. Takes a few tries though before it does so, as if it may be dumping/leaking fuel maybe. Let the car run for about 1h and half bled the coolant system and theyre were no issues with temps or oil pressure.

Decided to take the car for a shakedown run around the block after putting in some fresh plugs and as soon as you give it throttle it starts sputtering, back firing and slowly rpms drop and car stalls.

Now when you start in first gear the car bucks and back fires alot, change it to second gear and it gets worse.?? What would cause this to happen?

Also the guy I built the car for said that last year he had problems besides a chunk of apex seal missing. He said that when the odometer displayed numbers the car would drive fine with no hickups( prior to seal damage), when the odometer doesnt display the car would not rev past 2500 rpm, slowly creeping past the studder at 2500 rpm. He would then bring it up up to 4500 rpm it would not pass it at all.

What would be causing the crazy studder with throttle input?
When at ilde and I open the throttle by hand slowly lots of back firing and then stalls??
Has anyone had experiance with cluster problems and could it be related to the car not running properly and so rough?

Any help would be great. I will also try to post a video of this happening.

 

First thing to check is to make sure you don't have the CAS connectors mixed up. If you do, it will have a similar problem (the car will start and idle, but will buck and not accelerate).

 

Also to add to my previous comment, a few other things that commonly get mixed up which will cause operating problems:

* Coolant and Fuel thermosensor connectors. They are the same sensor type and the connections are in fairly close proximity.

* Ignition harness coil connections. There is a specific color order for those to be connected.

 

Thanks for the tip. It was the CAS connectors that were crossed. Car is running perfect now.

 

Also the guy I built the car for said that last year he had problems besides a chunk of apex seal missing.

He said that when the odometer displayed numbers the car would drive fine with no hickups( prior to seal damage), when the odometer doesnt display the car would not rev past 2500 rpm, slowly creeping past the studder at 2500 rpm. He would then bring it up up to 4500 rpm it would not pass it at all.

Is this an ecu/wiring problem or is it a guage cluster issue?

 

maybe is running on limp mode ?

 

possible aswell. I found a thread about the 3000 rpm hesitation so could be a grounding issue. this may fix the prob but not sure about the odometer not displaying.

 

Well changed out ECU and still the same hesitation. Going to finish redoing the grounds and see if it helps at all.

Still no answer about the odometer not displaying? Anybody have this issue?

 

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/just-got-done-figuring-out-how-fix-fd-odometer-599220/