I have a 91 LS that I just got done putting in a b16a1 OBD0. It ran beautifully for about 2 days and then it started this sputtering/hesitation issue and was extremely low on power. This only seemed to happen when it was warmed up. It would run almost flawlessly until like 20 minutes into driving. (maybe because the ECU was operating in open loop?). The symptoms remind of that of a missfire. It also has a rough start up. It usually takes 5 seconds for the engine to start and then it immediately shoots to 2300 until its warmed up and then it goes down to 300 - 400 rpm. At that point I try driving it and the hesitation/missfire symptom occurs along with the engine completely shutting off at idle sometimes. My fuel economy seems horrible like maybe 15 mpg when these problems happen and the other day I noticed what seemed to be stains of gas mist on my bumper from my exhaust. Since the b16a1 exhaust manifold has two exhaust holes to the downpipe and 2 o2 sensors and my old b18 manifold only has one hole and one 02 sensor I’m using one 02 sensor instead of 2 o2 sensors. I just spliced my one 02 sensor into the secondary o2 sensor wire to “trick” the ECU into thinking I’m running 2 o2 sensors. I’m not sure if this is the problem. I’ve tried many things and nothing has helped. This problem has been troubling me for over a month.
Things Ive done/replaced
new fuel pump
new fuel filter
new distributor
new spark plugs/wires
bypassed pcv valve
swapped ECU’s
I really miss how fun this car was when it was running good. any help/advice would be greatly appreciated.
Could be the cap n rotor or I recently went threw this only my issue was no power to the fuel pump which worked sometimes but I installed newer grounds and had to convert back to odb0 I was running odb1 rywire jumper which was blew my ignition coil on my because the pins were backwards I switched them around but about 2-3 hours of trying to start fried my coil in my anyways re check grounds and check the fuses I’m not sure what else make Shure everything has 12 volts running to it my advice
I have a 91 LS that I just got done putting in a b16a1 OBD0. It ran beautifully for about 2 days and then it started this sputtering/hesitation issue and was extremely low on power. This only seemed to happen when it was warmed up. It would run almost flawlessly until like 20 minutes into driving. (maybe because the ECU was operating in open loop?). The symptoms remind of that of a missfire. It also has a rough start up. It usually takes 5 seconds for the engine to start and then it immediately shoots to 2300 until its warmed up and then it goes down to 300 - 400 rpm. At that point I try driving it and the hesitation/missfire symptom occurs along with the engine completely shutting off at idle sometimes. My fuel economy seems horrible like maybe 15 mpg when these problems happen and the other day I noticed what seemed to be stains of gas mist on my bumper from my exhaust. Since the b16a1 exhaust manifold has two exhaust holes to the downpipe and 2 o2 sensors and my old b18 manifold only has one hole and one 02 sensor I’m using one 02 sensor instead of 2 o2 sensors. I just spliced my one 02 sensor into the secondary o2 sensor wire to “trick” the ECU into thinking I’m running 2 o2 sensors. I’m not sure if this is the problem. I’ve tried many things and nothing has helped. This problem has been troubling me for over a month.
Things Ive done/replaced
new fuel pump
new fuel filter
new distributor
new spark plugs/wires
bypassed pcv valve
swapped ECU’s
I really miss how fun this car was when it was running good. any help/advice would be greatly appreciated.[/QUOTE]
UPDATE
I ended up using an aftermarket header and welded 2 bungs for the o2 sensors and screwed both in instead of running both wires to the 1 o2 sensor and that was it. I’ve been driving it for about a week now and the hesitation symptoms seem to be gone and my power is back. The only problem is my exhaust sits very low because I had to make a spacer for my header but that is getting fixed. If anyone has the b16a1 and is having these problems I HIGHLY ADVISE you to try the 2 o2 sensors if you’re only using one. I didn’t think it was the problem but each o2 sensor reads a pair of cylinders and it will run either rich or lean.