new SR20DET swap running bad - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

lightningph · 10-23-2006, 08:23 PM

I've got a Redtop in an 89 S13. The ECU is throwing a MAF sensor error. I replaced it and it is still not running right.
I mesured the voltage from the MAF sensor at the ECU to be
1.3V @ 800 RPM
1.54 @ 1500
2.4 @ about 3000 (see below as to why it is about)
These values seem close enought to the specs that I think there is something else wrong. I have it wired up where
A=12V power
B= signal ground
C=signal
It idles at about 800RPM even after it warms up, but dips to 400 breafly after revving it. Before it gets warm, ideling around 2k RPM if you give it gas it bogs acting like it is going to stall before reving. It cannot be held at an RPM either revs or drops to idle. It is like an on and off switch. I can tell the fuel mix is supper rich by the smell.
I have a O2 meter that reads rich and then goes lean before going blank for a while before reading rich again. Durring this time the car will idle with no indication there was any change. I may have a bad O2 sensor but unplugging it does not change anything.
Could the ECU be bad? Is there anything else it could be? :hammer:
Thanks for any help!

10-23-2006, 08:23 PM	#1
lightningph Join Date: Nov 2004 Location: franklin, tn Posts: 17 Trader Rating: (0) Feedback Score: 0 reviews	new SR20DET swap running bad I've got a Redtop in an 89 S13. The ECU is throwing a MAF sensor error. I replaced it and it is still not running right. I mesured the voltage from the MAF sensor at the ECU to be 1.3V @ 800 RPM 1.54 @ 1500 2.4 @ about 3000 (see below as to why it is about) These values seem close enought to the specs that I think there is something else wrong. I have it wired up where A=12V power B= signal ground C=signal It idles at about 800RPM even after it warms up, but dips to 400 breafly after revving it. Before it gets warm, ideling around 2k RPM if you give it gas it bogs acting like it is going to stall before reving. It cannot be held at an RPM either revs or drops to idle. It is like an on and off switch. I can tell the fuel mix is supper rich by the smell. I have a O2 meter that reads rich and then goes lean before going blank for a while before reading rich again. Durring this time the car will idle with no indication there was any change. I may have a bad O2 sensor but unplugging it does not change anything. Could the ECU be bad? Is there anything else it could be? :hammer: Thanks for any help!