AT WITS END!! (hair pulling , help!)

[Ghettopoptart]

Ok , lets start by saying i made apost about the injectors a while back and got decent help, it fixed allot of my fuel issue but i still have something going on.

I have a 1991 Single Cam 240, It has a miss on cyl number 3, its a fuel issue bc it fires just the injector plug doesnt fire, we have replaced the following.

Injector plugs
WHOLE wiring harness
Distributor
injectors
cleaned the fuel rail
Plugs

And was told an auto single cam ecu would work, i put the auto ecu in there to see but it wont even give fuel to anything. So either the ecu itself is bad or isnt working. Maybe i need another 5spd ecu but...the car has had an engine swap , on the old engine, the number 3 cyl was missing its butt off...so can anyone tell me what could cause it to follow another engine, wiring harness, injectors, plugs and distributor over. I am at witts end, i will be getting a single cam 5spd ecu from the local Pull a part soon, if that doesnt fix it, i will lose more hair!

Help!? :bowdown:

[Kingtal0n]

WOW you are spending all this time and money on a SOHC KA?

My recommendation: buy a twin cam KA for $300-$500 and call it a day....

trying to figure out whats wrong with a SOHC KA is like trying to decide whether to moldy bread is worth eating when your starving. just buy a new loaf, oaf!

Technical response:
Realizing you might still want to diagnose this...

#1 make sure the positive on the injector has +12V
#1.5 do a compression and leakdown test on cyl 3
#2 make a new ground wire from ECU inj #3 to the injector itself (bypass harness)
#3 try a different injector
#4 swap plugs (take #2 and put it on #3 to make sure the ECU is firing the injector...)
#4.5 get a real motor
#5 profit

[r20crazy]

I would put money on #1.5 above given you have tried most else.

[Ghettopoptart]

ok, first off, telling me to switch to a twin cam is not helping. so please keep those posts to yourself, for a stock dd the motor is fine.

i have not done a compression test.. i have taken the #4 injector plug, and put it on #3 injector, and #3 started working. so that rules out a problem with the motor itself, or the injector... both wires on the injector plug test hot... as do all of the other injector plugs, when the car is not running. injector plugs do not have a designated hot and ground. i have not tested it while it was running, but it does however prove that it's not a problem with the wiring. i have replaced the distributor, wiring harness, and injectors. and the symptoms have not changed. so the ecu is the only constant. i'm really leaning towards that being the problem

[Ghettopoptart]

It was ECU, :cool:

Runs like a champ now.

[r20crazy]

glad you got it sorted out. thanks for posting the solution to your issue as well, as most people don't.

[Ghettopoptart]

yah it was the only logical thing , i wasnt 100% but.. it was the only constant to every thing we tried the ecu stayed the same...

ill post back more if something else goes wrong i cant deduce! ha

[Doluck]

It was ECU, :cool:

Runs like a turd now.

Its a SOHC! .... But dont worry, I'll fix that misprint for you!

FIXED!!!! :D

[KASilviaAR]

I'll give SOCK (SOHC) Props... 4 less valves=4 less things to break!!