Need assistance with misfire
Thread Starter
Drifting
Joined: May 2012
Posts: 1,623
Likes: 51
From: Gastonia North Carolina
Need assistance with misfire
Ok bought a 1994 coupe automatic car few weeks back with a blown head gasket. Heads freshened and surfaced, the car is back together and running.
It has a surging idle, the CE light revealed 02 sensor front bank 2. Havent replaced yet but will tomorrow. The fuel pressure is showing 39 psi at idle.
Driving the car down the road it misses to the point the trans is slipping in and out of OD?
Plan on replacing the fuel pump and oxygen sensors tomorrow. What about the injectors? Was 1994 compatible with the ethanol fuel? Or could the injectors be causing the mis?
Any idea's are appreciated!
It has a surging idle, the CE light revealed 02 sensor front bank 2. Havent replaced yet but will tomorrow. The fuel pressure is showing 39 psi at idle.
Driving the car down the road it misses to the point the trans is slipping in and out of OD?
Plan on replacing the fuel pump and oxygen sensors tomorrow. What about the injectors? Was 1994 compatible with the ethanol fuel? Or could the injectors be causing the mis?
Any idea's are appreciated!
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Check vacuum lines for a leak.
Check EGR valve to see if it moves freely and is closed.
Check fuses on passenger side #22 and 23. Each fuse supplies the voltage for 4 injectors. One fuse can be blown and the engine can run.
Check the vacuum line of the FPR to make sure it is dry and no fuel in it.
Goes without saying, check the wires and plugs and any sparking.
I don’t think an O2 sensor would cause this. But the mileage and A/F mix will not be correct (will be rich).
It does not sound like a optispark problem.
Check EGR valve to see if it moves freely and is closed.
Check fuses on passenger side #22 and 23. Each fuse supplies the voltage for 4 injectors. One fuse can be blown and the engine can run.
Check the vacuum line of the FPR to make sure it is dry and no fuel in it.
Goes without saying, check the wires and plugs and any sparking.
I don’t think an O2 sensor would cause this. But the mileage and A/F mix will not be correct (will be rich).
It does not sound like a optispark problem.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,623
Likes: 51
From: Gastonia North Carolina
Check vacuum lines for a leak. No vacuum leaks found yet.
Check EGR valve to see if it moves freely and is closed. Will check egr.
Check fuses on passenger side #22 and 23. Each fuse supplies the voltage for 4 injectors. One fuse can be blown and the engine can run. Will check fuses.
Check the vacuum line of the FPR to make sure it is dry and no fuel in it.
Will verify FPR lines for dry condition.
Goes without saying, check the wires and plugs and any sparking. plug wires will be changed tomorrow as well.
I don’t think an O2 sensor would cause this. But the mileage and A/F mix will not be correct (will be rich).
It does not sound like a optispark problem.
Check EGR valve to see if it moves freely and is closed. Will check egr.
Check fuses on passenger side #22 and 23. Each fuse supplies the voltage for 4 injectors. One fuse can be blown and the engine can run. Will check fuses.
Check the vacuum line of the FPR to make sure it is dry and no fuel in it.
Will verify FPR lines for dry condition.
Goes without saying, check the wires and plugs and any sparking. plug wires will be changed tomorrow as well.
I don’t think an O2 sensor would cause this. But the mileage and A/F mix will not be correct (will be rich).
It does not sound like a optispark problem.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,623
Likes: 51
From: Gastonia North Carolina
Thread Starter
Drifting
Joined: May 2012
Posts: 1,623
Likes: 51
From: Gastonia North Carolina
Update still need help!
Changed the wires and checked fuel pressure with vac line loose it has 48lbs on the analog gauge.
The car shows sysmtoms of hard starts, spinning over for 5-9 secs before running.
Once the car is running it has a dead misfire. Idles at 750 then jumps to 1100.
Once in gear the idle drops to 600-650 and the car shakes, give it a little gas and it smooths out.
Took it down the road and it clearly has a dead mis while applying the throttle. Once your cruising at speed it seems to smooth out.
The trans is shifting hard during acceleration?
What is going on with this car. Only codes is for an oxygen sensor.
Need Help Bad.
Changed the wires and checked fuel pressure with vac line loose it has 48lbs on the analog gauge.
The car shows sysmtoms of hard starts, spinning over for 5-9 secs before running.
Once the car is running it has a dead misfire. Idles at 750 then jumps to 1100.
Once in gear the idle drops to 600-650 and the car shakes, give it a little gas and it smooths out.
Took it down the road and it clearly has a dead mis while applying the throttle. Once your cruising at speed it seems to smooth out.
The trans is shifting hard during acceleration?
What is going on with this car. Only codes is for an oxygen sensor.
Need Help Bad.
Thread Starter
Drifting
Joined: May 2012
Posts: 1,623
Likes: 51
From: Gastonia North Carolina
Update still need help!
Changed the wires and checked fuel pressure with vac line loose it has 48lbs on the analog gauge.
The car shows sysmtoms of hard starts, spinning over for 5-9 secs before running.
Once the car is running it has a dead misfire. Idles at 750 then jumps to 1100.
Once in gear the idle drops to 600-650 and the car shakes, give it a little gas and it smooths out.
Took it down the road and it clearly has a dead mis while applying the throttle. Once your cruising at speed it seems to smooth out.
The trans is shifting hard during acceleration?
What is going on with this car. Only codes is for an oxygen sensor.
Need Help Bad.
Changed the wires and checked fuel pressure with vac line loose it has 48lbs on the analog gauge.
The car shows sysmtoms of hard starts, spinning over for 5-9 secs before running.
Once the car is running it has a dead misfire. Idles at 750 then jumps to 1100.
Once in gear the idle drops to 600-650 and the car shakes, give it a little gas and it smooths out.
Took it down the road and it clearly has a dead mis while applying the throttle. Once your cruising at speed it seems to smooth out.
The trans is shifting hard during acceleration?
What is going on with this car. Only codes is for an oxygen sensor.
Need Help Bad.
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Thread Starter
Drifting
Joined: May 2012
Posts: 1,623
Likes: 51
From: Gastonia North Carolina
