Wounded_Fighter Posted October 29, 2019 Share Posted October 29, 2019 Looking for anything wrong or improvements I should look at? I know I'm stuck in open loop, and stuck in lean mode no matter what my o2 sensor reads 0.2v all the way to 4.95v Short term and long term never move either? Image from the xjbluetalk app with rem v5 bluetooth Idle after 30mins of operation 70mph 25mins operating. Link to comment Share on other sites More sharing options...
Ωhm Posted October 29, 2019 Share Posted October 29, 2019 Idle RPM's seem high (900). Does the EXHAUST PID switch between LEAN and RICH rapidly (close to the speed of light)? Does O2S voltage switch between 0.2v and 4.95v rapidly? OPEN LOOP will not change FUEL TRIM values. I'll take it that 5% for TPS is correct. Link to comment Share on other sites More sharing options...
Wounded_Fighter Posted October 29, 2019 Author Share Posted October 29, 2019 14 minutes ago, Ωhm said: Idle RPM's seem high (900). Does the EXHAUST PID switch between LEAN and RICH rapidly (close to the speed of light)? Does O2S voltage switch between 0.2v and 4.95v rapidly? OPEN LOOP will not change FUEL TRIM values. I'll take it that 5% for TPS is correct. Idle 820-900ish Lean/rich doesn't appear to move, switch, flicker at all O2Sv will switch quickly on road. But on it's own no. Just something I noticed driving that no matter where the voltage was lean/rich didnt change. Tps seems accurate to me. If anything it's more closer to 0. I have the throttlebody overbore. Edit: just got it from nick o2sv Rich/lean only updates in closed loop Link to comment Share on other sites More sharing options...
Big Dan Posted October 29, 2019 Share Posted October 29, 2019 I have the same issue...my O2 sensor isnt functioning, I'm assuming. I had an AC Delco, in there, and swapped it out for NTK last night. I'm hoping it was just a sensor problem. Link to comment Share on other sites More sharing options...
Ωhm Posted October 29, 2019 Share Posted October 29, 2019 May have to compare TPS(%) with actual TPS (v) using a voltmeter. Use cruisers tip adjustment procedure. High Idle may also mean your sucking air somewhere. Possible faulty O2S (slow or NO response). Link to comment Share on other sites More sharing options...
Wounded_Fighter Posted October 29, 2019 Author Share Posted October 29, 2019 2 minutes ago, Ωhm said: May have to compare TPS(%) with actual TPS (v) using a voltmeter. Use cruisers tip adjustment procedure. High Idle may also mean your sucking air somewhere. Possible faulty O2S (slow or NO response). O2s might be good, just got a reply from nick on it. Rich/lean only updates in closed loop It might be sucking at on the intake manifold gasket... I had hell tightening the bolts with the pacesetters Link to comment Share on other sites More sharing options...
Ωhm Posted October 29, 2019 Share Posted October 29, 2019 1 minute ago, Wounded_Fighter said: Rich/lean only updates in closed loop I'll remember that. Good tip there. Link to comment Share on other sites More sharing options...
Wounded_Fighter Posted October 29, 2019 Author Share Posted October 29, 2019 23 minutes ago, Ωhm said: I'll remember that. Good tip there. The sensor itself may read lean/rich but ecu will only notice if its closed loop it sounds like. Link to comment Share on other sites More sharing options...
Warren Mohler Posted October 29, 2019 Share Posted October 29, 2019 o2 sensor just gives a reading of exhaust gas, lean/rich is ecu trying to maintain 14.7to1 ratio which can never be obtained hence lean/rich Link to comment Share on other sites More sharing options...
Warren Mohler Posted October 29, 2019 Share Posted October 29, 2019 I haven't looked at a screen like this in a long time, question BAR is reading 15.1 that's barometric pressure I believe should that not be around 30 or am I just feeling light Link to comment Share on other sites More sharing options...
Ωhm Posted October 29, 2019 Share Posted October 29, 2019 Units used for pressure are in PSI. Link to comment Share on other sites More sharing options...
Ωhm Posted October 29, 2019 Share Posted October 29, 2019 18 minutes ago, Warren Mohler said: o2 sensor just gives a reading of exhaust gas O2S only read oxygen in the exhaust gas. 14.7:1 is O2S voltage of 2.5v. Link to comment Share on other sites More sharing options...
Warren Mohler Posted October 29, 2019 Share Posted October 29, 2019 its been a while, you are right oxygen in exhaust, my bad Link to comment Share on other sites More sharing options...
Ωhm Posted October 29, 2019 Share Posted October 29, 2019 Link to comment Share on other sites More sharing options...
fiatslug87 Posted October 29, 2019 Share Posted October 29, 2019 TPS should be 17% at idle. Test your O2 sensor resistance between A&B should be 5-7 ohms. Edit: I see your O2 sensor is switching so it looks like it's working properly. Link to comment Share on other sites More sharing options...
Wounded_Fighter Posted October 29, 2019 Author Share Posted October 29, 2019 I kept my eye on some different numbers this morning. Mainly stft and loop It is switching and attempting closed loop but in most cases stft hits 255 and switches to open again. Had it hit 0 once. Link to comment Share on other sites More sharing options...
87MJTIM Posted October 29, 2019 Share Posted October 29, 2019 If you STFT jumps to 255 (or 0) and remains there, the ECU will default to Open Loop. The O2 sensor is detecting a lean condition. This is according to the Renix Fuel Injection manual pp. 2-3 where it describes "Pulse Width Modification (ALFACL)" and Open v. Closed Loop. Possible causes: low fuel pressure, clogged injector, or faulty O2 sensor. Additionally, you could have an intake leak allowing more air into the system. Possible manifold gasket or cracked exhaust manifold. Link to comment Share on other sites More sharing options...
cruiser54 Posted October 29, 2019 Share Posted October 29, 2019 55 minutes ago, 87MJTIM said: If you STFT jumps to 255 (or 0) and remains there, the ECU will default to Open Loop. The O2 sensor is detecting a lean condition. This is according to the Renix Fuel Injection manual pp. 2-3 where it describes "Pulse Width Modification (ALFACL)" and Open v. Closed Loop. Possible causes: low fuel pressure, clogged injector, or faulty O2 sensor. Additionally, you could have an intake leak allowing more air into the system. Possible manifold gasket or cracked exhaust manifold. Time to spray around suspected areas with carb cleaner. Link to comment Share on other sites More sharing options...
Wounded_Fighter Posted October 29, 2019 Author Share Posted October 29, 2019 56 minutes ago, 87MJTIM said: you could have an intake leak allowing more air into the system. Possible manifold gasket or cracked exhaust manifold. Going to check gasket. Header is new. 1 minute ago, cruiser54 said: Time to spray around suspected areas with carb cleaner. Had same thought... It was difficult to tighten the manifold bolts down to begin with even with a new set. Link to comment Share on other sites More sharing options...
cruiser54 Posted October 29, 2019 Share Posted October 29, 2019 23 minutes ago, Wounded_Fighter said: Going to check gasket. Header is new. Had same thought... It was difficult to tighten the manifold bolts down to begin with even with a new set. Take the air cleaner box out. Link to comment Share on other sites More sharing options...
Wounded_Fighter Posted October 29, 2019 Author Share Posted October 29, 2019 7 hours ago, cruiser54 said: Take the air cleaner box out. Tons was out, to include said box. Link to comment Share on other sites More sharing options...
87MJTIM Posted October 29, 2019 Share Posted October 29, 2019 50 minutes ago, Wounded_Fighter said: Tons was out, to include said box. Don't you think that was a little overkill? I mean, I can remove the air box without pulling the head. Link to comment Share on other sites More sharing options...
Wounded_Fighter Posted October 29, 2019 Author Share Posted October 29, 2019 43 minutes ago, 87MJTIM said: Don't you think that was a little overkill? I mean, I can remove the air box without pulling the head. Nah pistons were in the way too. Link to comment Share on other sites More sharing options...
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