TeamFervor'sSavannah

Hey guys, got the new motor in with my original S4 NA tranny with some help.

The engine was running fine when I pulled it, now every time I touch the gas pedal, it dies, it also dies if we let it idle.

Now, there is a plug in the passenger side engine bay, near the front behind the headlight that is not included on the new engine harness, but was on my old one. The plug connects to about an 8 inch rectangular box, I believe this is it in the picture.



This seems to be the only difference between the engines. Also, why would there be two ECUs on my parts car (E326 and E327, both were underneath the passenger kickboard, and which one should I use? Both were plugged in.)

Fuel pump has less than 3k miles on it, already verified gas lines are correct, we're getting spark, air, and fuel. Anyone recognize this symptom?

HAILERS2

I can't see the item in the picture. BUT it probably is the Solenoid Resistor package that is used on 1986 and early 1987 series four cars.

The cars that have one of those use low resistance injectors. The cars that do not have the solenoid resistor use high resistance fuel injectors.

So I'd say your old or original car had low impedence injectors and had the solenoid resistor package in the fuel injector circuit. And you new engine with it's own EM harness uses the high impedece injectors and does not need that solenoid resistor package (that item has a large five wire plug on it).

Either the N326 or N327 will work on either engine with nothing abnormal.

Are you SURE the elect plug is attached to the AFM??? Starting a RX does not require the afm until AFTER the engine actually start and then it is Required for running. So if the plug was off the afm then the car would start but not stay running.

Or say that is not the problem. Try this. There is a yellow two wire/socket connector nearby to the boost/pressure sensor. Jumper the two sockets in the plug with a piece of wire and turn the key ON. You should hear the fuel pump running continuously. Does that happen? IF it does, try starting the car again to see if it keeps runing.

Or you have a very large air leak like the half inch hose off the nipple on the black intake duct approx a foot from the throttle body or some other very large air leak similar to that. Like the bypass solenoid valve or BAC on the left side of the engine having a hose off or ???? who knows.

HAILERS2

https://www.rx7club.com/showthread.p...chassis+number

I posted a jpg of someones solenoid resistor package on this thread. Look and see if this is it.

TeamFervor'sSavannah

This is it. And the previous owner hardwired the fuel pump to run on ACC, and I never touched it, and it does this all the time.

I'll see if I can't run over sometime today or tomorrow and have a look at it. I will also reconnect my old AFM which I know is working, and also clean the plugs.

satch

iTrader: (1)

At first blush it seems the car would be hard to start for the ACC fuses lose temporary power when the key is turned to start and doesn't return to having power until the key springs back to the "on" position from the start position.

TeamFervor'sSavannah

Well, its not a problem that the fuel pump is always running. The car will start and idle for a few seconds, and then die, even sooner if I touch the accelerator.

satch

iTrader: (1)

The point I am trying to make is the fuel pump will not run all the time if the key is turned to the "start" position "if" it is powered by an ACC fuse. Again, the "only" interior fuses which receive power when the key is turned to start are the fuses that are more formally known as IG1 fuses and these fuses receive power constantly when the key is turned to on or better ( meaning on or the start position). So if your fuel pump is truly powered by an ACC fuse then it will turn off w/key to start. This is not a ventured guess. "All" interior fuses lose power w/key to start except for the IG1 fuses.