Like the title says, I'm having issues with my YJ 2.5. When the engine is under normal operating temperature it stutters between the rpms mentioned. So far I've checked fuel pressure, although it was good, I replaced the fuel pump (in case the check valve was faulty and draining back to the tank), regulator, and fuel lines between the filter and tank, vapor lines and vent grommets which were rotted. The fuel lines were hard and collapsed. I also replaced vacuum fittings and brake boosted grommet to the air intake hose since it was rotted. Vacuum seems good now.
Spark plugs have normal color, the o2 sensor is a year old and so are the TPS, air intake temperature and engine coolant sensors and complete exhaust system including headers.
My YJ has 4.0 TB but I reused the 2.5 TPS and idle valve (which is old). The issue started several months after the TB swap so I don't think this is the issue.
When the stuttering occurs the idle trends to stay high and slowly drops.
The issue does not happen all the time. A few times it has happened before the engine warms up but most of the time after it is warmed up.
I'm wondering if the idle air valve or crank position sensor could be issue. I also heard that a worn distributor/pickup coil cause this problem.
I'm stumped. I'm planning on keeping this jeep so I want to fix the issue.
What do you guys/gals think? Crank sensor, distributor or something else.
Thanks for the help.
Spark plugs have normal color, the o2 sensor is a year old and so are the TPS, air intake temperature and engine coolant sensors and complete exhaust system including headers.
My YJ has 4.0 TB but I reused the 2.5 TPS and idle valve (which is old). The issue started several months after the TB swap so I don't think this is the issue.
When the stuttering occurs the idle trends to stay high and slowly drops.
The issue does not happen all the time. A few times it has happened before the engine warms up but most of the time after it is warmed up.
I'm wondering if the idle air valve or crank position sensor could be issue. I also heard that a worn distributor/pickup coil cause this problem.
I'm stumped. I'm planning on keeping this jeep so I want to fix the issue.
What do you guys/gals think? Crank sensor, distributor or something else.
Thanks for the help.