Misfire fixed by increasing fuel pressure?
Posted: Sun Apr 19, 2015 7:55 pm
Hi Everyone!
I have a 1996 Prelude Vtec that developed a misfire a few months ago. It did produce a code for cylinder 1 misfire. I did everything in the book to correct the problem. Nothing helped and I took it to a local race shop, they went through everything, determined it was running too lean but couldn't find the cause. They ended up using an adjustable fuel pressure regulator to increase fuel pressure. The car runs good but I'm still curious about the root cause of this problem. The fuel pressure was in spec before (30-39 psi). The shop put it on a dyno and tuned in to a higher fuel pressure, in the 40's i think, but this is way above the spec specified in the manual.
Here is the list of everything that has been done:
- new spark plugs/wire/rotor cap/ignitor
- new fuel injectors/filter
- egr valve & ports cleaned
- cleaned manifold & throttle body
- check for vacuum leaks
- adjusted valve lash
- check all sensors at the ECU (voltage drop tests)
- check timing belt
- fuel pressure was normal before the fix
- check injector and spark pulse with oscilloscope
I have a 1996 Prelude Vtec that developed a misfire a few months ago. It did produce a code for cylinder 1 misfire. I did everything in the book to correct the problem. Nothing helped and I took it to a local race shop, they went through everything, determined it was running too lean but couldn't find the cause. They ended up using an adjustable fuel pressure regulator to increase fuel pressure. The car runs good but I'm still curious about the root cause of this problem. The fuel pressure was in spec before (30-39 psi). The shop put it on a dyno and tuned in to a higher fuel pressure, in the 40's i think, but this is way above the spec specified in the manual.
Here is the list of everything that has been done:
- new spark plugs/wire/rotor cap/ignitor
- new fuel injectors/filter
- egr valve & ports cleaned
- cleaned manifold & throttle body
- check for vacuum leaks
- adjusted valve lash
- check all sensors at the ECU (voltage drop tests)
- check timing belt
- fuel pressure was normal before the fix
- check injector and spark pulse with oscilloscope