Not sure if anyone is following but here is the preface:



1994 touring--its a friends car

Grenaded motor a few months ago. I installed:



Atkins 13B Ported/Polished Motor



EVERYTHING else is stock on the motor.



After getting the car started and running, aside from the misc cooling issues and vaccum line issues these things have, its running "ok"



The car is throwing code 5 (which is a knock sensor code.) The car is puffing black smoke at idle (unburnt fuel) My guess is the ECU is picking up the knock sensor code and dumping in extra un-needed fuel to compensate for the knock. Is it possible the car is actually knocking at idle? I've cleared teh codes before, double checked they were cleared, fired it up, only to see the CEL go on again, resulting in a code 5 once again.



Since the motor is ported and its on stock everything else, is it possible its sucking in to much air for the stock computer to handle, and its actually going lean at idle and knocking? Anyone have any input?

 

Lean condition at idle would cause it to stall. Overly rich mixture would show up on the plugs as wet or even fouled. Could have an injector stuck open or something wierd, but typically when the car goes into limp mode it doesn't throw a ton of fuel in the maps untill you get closer to boost.

 

I should probably start by pulling the plugs I guess(although I JUST bought brand new ones). I dont see how an injector would stick however. It was running fine (just knocking) before I put the block in

 

[quote name='Booztd 3' date='Aug 1 2005, 10:23 AM']I should probably start by pulling the plugs I guess(although I JUST bought brand new ones). I dont see how an injector would stick however. It was running fine (just knocking) before I put the block in


[/quote]



If the plugs were fouled, they wouldn't be burning the fuel properly anyhow, which would result in a horrible running car that blew black smoke from unburnt fuel. I kinda doubt you'd get a knock code from that, but who knows. Could be faulty knock readings thowing a code.

 

How do you determine if an injector is stuck open?

 

Is there a trick, to tricking the ecu into thinking its reading normal for the knock sensor? I know on the 300's, you can stick a 1000 ohm resistor in the knock sensor harness and it tricks the computer into thinking a known working knock sensor in place. This could possibly eliminate the idea that its runnign way rich.



The car acts just fine at 2k rpm, or whatever you're driving at aside from the idle issue

 

[quote name='eyecandy' date='Aug 1 2005, 11:09 AM']How do you determine if an injector is stuck open?


[/quote]





I second this question. I think if mine were stuck open it'd be pouring black smoke all the time

 

I'm not sure either to be honest.



The resistor thing is a good idea. I'm not sure if anyone has ever tried on the FD, but I have read where people use that as a technique for situations like this.

 

The last time I had to do the resistor trick, i didnt have a resistor so I took one of those rockford fosgate bass ***** (had an extra one laying around) and dissasembled it, to make an adjustable resistor



I just soldered a wire on each of the leads and I could turn the resistance anywhere from 0ohm-1000ohms. Pretty nifty eh?

 

unscrew the knock sensor... and ziptie it onto the side