Cottontail
Three-De Off-Road
- Location
- Nashville, TN
1990 XJ...4.0L
Now here is the issue. I have had considerable hesitation under acceleration as well as some backfiring in the last 90-120 miles or so.
I decided to check my fuel pressure first. I put a rag under the schrader valve (with the truck off and the key out) and depressed the valve to release pressure. I bet it sprayed fuel for 15 seconds. I know that doesn't sound long, but it is when you are watching fuel spray from your fuel rail.
I hooked up the pressure tester, and turned the key over to enegize the fuel pump. I got a reading around 10-15 PSI. When I pushed the plunger on the pressure guage to empty the fuel it ran for another 15-20 seconds into the pop bottle I was collecting it in.
I tried it again, and again got 10-15 PSI and it drained another 15-20 seconds. All said in those 2 tests, I drained almost 1/3 of a cup of fuel into the pop bottle.
Something is not adding up. It has always had a hesitation, but it is getting worse since my last fill up when I used a fuel injector cleaner in the tank. I also replaced the fuel filter at that time.
Any ideas....by the way new items in the last 500 miles:
plugs, wires, battery, cables, injectors, fuel pressure regulator, fuel pump, fuel filter, CPS, distributor, computer, thermostat, coolant overflow bottle, ballast resistor
Thanks
Now here is the issue. I have had considerable hesitation under acceleration as well as some backfiring in the last 90-120 miles or so.
I decided to check my fuel pressure first. I put a rag under the schrader valve (with the truck off and the key out) and depressed the valve to release pressure. I bet it sprayed fuel for 15 seconds. I know that doesn't sound long, but it is when you are watching fuel spray from your fuel rail.
I hooked up the pressure tester, and turned the key over to enegize the fuel pump. I got a reading around 10-15 PSI. When I pushed the plunger on the pressure guage to empty the fuel it ran for another 15-20 seconds into the pop bottle I was collecting it in.
I tried it again, and again got 10-15 PSI and it drained another 15-20 seconds. All said in those 2 tests, I drained almost 1/3 of a cup of fuel into the pop bottle.
Something is not adding up. It has always had a hesitation, but it is getting worse since my last fill up when I used a fuel injector cleaner in the tank. I also replaced the fuel filter at that time.
Any ideas....by the way new items in the last 500 miles:
plugs, wires, battery, cables, injectors, fuel pressure regulator, fuel pump, fuel filter, CPS, distributor, computer, thermostat, coolant overflow bottle, ballast resistor
Thanks