raymondvillain
New Member
1990 Acura Integra LS, replaced the head gasket, timing belt, alternator, water pump, thermostat, fuel filter, injectors and seals, spark plugs, spark plug wires, distributor cap and rotor, and air filter. Also the valve cover gasket and cam shaft seals.
Got it all back together and it will only run on 3 cylinders, numbers 1, 2, and 3. Cylinder 4 is not firing.
And the "check engine" light on the dashboard stays on.
Cylinder 4 has spark. The fuel pressure is fine. When I disconnect the vacuum hose to the fuel pressure regulator the pressure jumps from 32 to about 41 psi.
I've swapped out the fuel injectors for cylinders 3 and 4 but nothing changes. Cylinder 3 is still firing, but not cylinder 4.
The compression is fine. Compression check gives cylinder 1 at 182.5, cylinder 2 is 161, cylinder 3 is 166, and cylinder 4 is 180.
I was extremely careful with the timing belt installation. The crankshaft sprocket was dead on the index mark on the block, and the "UP" spokes of the camshaft sprockets were both at the top of the arc, and the number 1 cylinder was at top dead center. I also checked the valve lash (after re-assembly) and it is within spec. I'm sure I got the timing correct. There is no slack in the timing belt, either. Neither is it too tight.
Don't have a scope, so I can't look at the voltage time history coming out of the electrical connectors to the injectors, but I know some sort of signal is present at the fuel injector electrical connector for cylinder 4 because I can see something going on when I hook up a multimeter to this connector.
Do I have to reset the PCM (powertrain control module)? I have a Haynes manual for this car but it doesn't say anything about resetting the PCM. I understand that the signals to the injectors come from the PCM, so maybe I need a new PCM. Is there a way to check the PCM?
Any and all suggestions will be greatly appreciated.
Got it all back together and it will only run on 3 cylinders, numbers 1, 2, and 3. Cylinder 4 is not firing.
And the "check engine" light on the dashboard stays on.
Cylinder 4 has spark. The fuel pressure is fine. When I disconnect the vacuum hose to the fuel pressure regulator the pressure jumps from 32 to about 41 psi.
I've swapped out the fuel injectors for cylinders 3 and 4 but nothing changes. Cylinder 3 is still firing, but not cylinder 4.
The compression is fine. Compression check gives cylinder 1 at 182.5, cylinder 2 is 161, cylinder 3 is 166, and cylinder 4 is 180.
I was extremely careful with the timing belt installation. The crankshaft sprocket was dead on the index mark on the block, and the "UP" spokes of the camshaft sprockets were both at the top of the arc, and the number 1 cylinder was at top dead center. I also checked the valve lash (after re-assembly) and it is within spec. I'm sure I got the timing correct. There is no slack in the timing belt, either. Neither is it too tight.
Don't have a scope, so I can't look at the voltage time history coming out of the electrical connectors to the injectors, but I know some sort of signal is present at the fuel injector electrical connector for cylinder 4 because I can see something going on when I hook up a multimeter to this connector.
Do I have to reset the PCM (powertrain control module)? I have a Haynes manual for this car but it doesn't say anything about resetting the PCM. I understand that the signals to the injectors come from the PCM, so maybe I need a new PCM. Is there a way to check the PCM?
Any and all suggestions will be greatly appreciated.