SR20DET Running Lean/ Limp Mode? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Kingtal0n · 03-20-2015, 08:02 PM

I had this exact problem with a wiring specialties harness. One of the pins that contacted the coilpack output (At the ecu plug) was only making contact sometimes. We tracked it down by individually twisting each coilpack output wire until the symptom appeared.

To fix it, at least temporarily, I shoved some bits of wire into the plug to make the contact patch "larger".

otherwise, it does sound like an ECU related issue. If you cannot cause the problem by twisting and pulling the wiring harness around, you should try a new ecu. Always keep a spare 62/E5 handy. heck, even I have one, and I dont even have an s13 sr20 anymore.

Here is some food for thought,
The wideband is telling you more than you realize. If a coilpack output failed, the wideband would read lean, it would pick up the oxygen leftover (unreacted) by the misfire.
So, misfires cause lean readings- yours is a rich reading? You need to describe the problem better. If the engine "sounds like it is missing" but the wideband is reading rich, again that points back to the ecu/maf/leaks....

Another possibility is that your "BOV" is getting stuck open and leaking to the atmosphere. That would also cause this same problem. Try plugging the BOV with a sock or tape or something to eliminate it as a possibility.

03-20-2015, 08:02 PM	#2
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 42 Posts: 4,829 Trader Rating: (17) Feedback Score: 17 reviews	I had this exact problem with a wiring specialties harness. One of the pins that contacted the coilpack output (At the ecu plug) was only making contact sometimes. We tracked it down by individually twisting each coilpack output wire until the symptom appeared. To fix it, at least temporarily, I shoved some bits of wire into the plug to make the contact patch "larger". otherwise, it does sound like an ECU related issue. If you cannot cause the problem by twisting and pulling the wiring harness around, you should try a new ecu. Always keep a spare 62/E5 handy. heck, even I have one, and I dont even have an s13 sr20 anymore. Here is some food for thought, The wideband is telling you more than you realize. If a coilpack output failed, the wideband would read lean, it would pick up the oxygen leftover (unreacted) by the misfire. So, misfires cause lean readings- yours is a rich reading? You need to describe the problem better. If the engine "sounds like it is missing" but the wideband is reading rich, again that points back to the ecu/maf/leaks.... Another possibility is that your "BOV" is getting stuck open and leaking to the atmosphere. That would also cause this same problem. Try plugging the BOV with a sock or tape or something to eliminate it as a possibility.