****Started this post on some other forums and haven't gotten much feedback, hoping this site will provide me with some answers*****
First let me apologize for another starting issue thread. However, I am looking to confirm that my suspicions of a bad fuel pump are the problem before I tackle such an in depth job.
My Wrangler: 1998, 4.0, 5 speed, 160k miles, 33" Tires
Ever since I have owned the Jeep (6 years now) it has had the long start issue. So I had have been anticipating the fuel pump going out for some time now. Just recently, within the last month, my Jeep has been hesitant to accelerate upon first drive of the day. After about 10 minutes of driving the Jeep would drive completely fine and be able to accelerate full throttle, half throttle, any position really. A week ago, after having sat for 4 days, I drove the Jeep home (about 10 minutes) and it was very hesitant (felt like not getting enough fuel under load) and especially when flooring the gas pedal it simply would not provide what I assume is adequate fuel to accelerate. I parked it when I got home and it sat for another 3 days. This morning (after sitting for 3 days) I went to start it and on first crank a loud pop came from the exhaust and it would not start. I feared a drop valve or something of the sort so I started checking oil for discoloration. Nothing. I did notice while checking under the hood there was some white smoke coming from my cold air intake. While I was under the hood I checked, spark plug wires were seated, and all of the throttle body sensors were seated. I think checked CPS and it was seated as well. I got back in the jeep and cranked the engine with the gas pedal floored. It started and I left it alone for about 5 minutes. After idling for 5 minutes I tried to Rev it up and it immediately died. I left it for about 6 hours after that and came back to it. 6 hours later it now starts and rev's but with a lot of stutter. I haven't driven it under load in gear for fear of it leaving me stranded. However I have shut it down and started it multiple times since then and it now starts and runs, and will rev, but with some stutter sometimes and a lot of stutter others. It seems to idle perfectly when I am not touching the gas pedal.
I am very torn about what it is. I replaced the CPS about 3 years ago with a Duralast (I know, not good) but it has been fine ever since. I don't know if it could be the Duralast has finally quit on me, or if it has something to do with the throttle body sensors? Spark plugs are champion generics and are about 4/5 years old with maybe 25k miles on them. I pulled one and it was fairly worn, certainly time to do plugs but I don't know if these symptoms point to plugs? I am cleaning the throttle bodytonight, and replacing the air filter. Doubt that will do the trick but doing those 2 things doesn't hurt.
There are currently no CEL's at all.
Any advice is greatly appreciated. If it comes down to fuel pump, which pump do I get with the Bosch now being impossible to find? Thank you again for the help!
-Colby
*****************UPDATE*******************
Went out today and bought a fuel pressure tester. Cleaned the throttle body and cold air intake filter and then ran the pressure test. Just turning the key on, the pump put out 30 PSI but started to slowly drain back. Started the Jeep and it held around 41 PSI. I rev'd it up while it was running and it would dip to 37 PSI for a quick second and then jump right back up to 41 PSI. Jeep seemed to be running better today, all though it was mid day so temp was right around 65. I know 41 PSI is about 8 PSI lower then its supposed to be. Should I still be thinking pump? Fuel pressure would also bleed off down to 0 after I shut the engine off at about 10 PSI a minute. Not very concerned with a long start issue, more worried about the pump just deciding to give up on me at an inopportune time. Maybe time to do plugs, wires, cap and rotor and see what result that yields?
First let me apologize for another starting issue thread. However, I am looking to confirm that my suspicions of a bad fuel pump are the problem before I tackle such an in depth job.
My Wrangler: 1998, 4.0, 5 speed, 160k miles, 33" Tires
Ever since I have owned the Jeep (6 years now) it has had the long start issue. So I had have been anticipating the fuel pump going out for some time now. Just recently, within the last month, my Jeep has been hesitant to accelerate upon first drive of the day. After about 10 minutes of driving the Jeep would drive completely fine and be able to accelerate full throttle, half throttle, any position really. A week ago, after having sat for 4 days, I drove the Jeep home (about 10 minutes) and it was very hesitant (felt like not getting enough fuel under load) and especially when flooring the gas pedal it simply would not provide what I assume is adequate fuel to accelerate. I parked it when I got home and it sat for another 3 days. This morning (after sitting for 3 days) I went to start it and on first crank a loud pop came from the exhaust and it would not start. I feared a drop valve or something of the sort so I started checking oil for discoloration. Nothing. I did notice while checking under the hood there was some white smoke coming from my cold air intake. While I was under the hood I checked, spark plug wires were seated, and all of the throttle body sensors were seated. I think checked CPS and it was seated as well. I got back in the jeep and cranked the engine with the gas pedal floored. It started and I left it alone for about 5 minutes. After idling for 5 minutes I tried to Rev it up and it immediately died. I left it for about 6 hours after that and came back to it. 6 hours later it now starts and rev's but with a lot of stutter. I haven't driven it under load in gear for fear of it leaving me stranded. However I have shut it down and started it multiple times since then and it now starts and runs, and will rev, but with some stutter sometimes and a lot of stutter others. It seems to idle perfectly when I am not touching the gas pedal.
I am very torn about what it is. I replaced the CPS about 3 years ago with a Duralast (I know, not good) but it has been fine ever since. I don't know if it could be the Duralast has finally quit on me, or if it has something to do with the throttle body sensors? Spark plugs are champion generics and are about 4/5 years old with maybe 25k miles on them. I pulled one and it was fairly worn, certainly time to do plugs but I don't know if these symptoms point to plugs? I am cleaning the throttle bodytonight, and replacing the air filter. Doubt that will do the trick but doing those 2 things doesn't hurt.
There are currently no CEL's at all.
Any advice is greatly appreciated. If it comes down to fuel pump, which pump do I get with the Bosch now being impossible to find? Thank you again for the help!
-Colby
*****************UPDATE*******************
Went out today and bought a fuel pressure tester. Cleaned the throttle body and cold air intake filter and then ran the pressure test. Just turning the key on, the pump put out 30 PSI but started to slowly drain back. Started the Jeep and it held around 41 PSI. I rev'd it up while it was running and it would dip to 37 PSI for a quick second and then jump right back up to 41 PSI. Jeep seemed to be running better today, all though it was mid day so temp was right around 65. I know 41 PSI is about 8 PSI lower then its supposed to be. Should I still be thinking pump? Fuel pressure would also bleed off down to 0 after I shut the engine off at about 10 PSI a minute. Not very concerned with a long start issue, more worried about the pump just deciding to give up on me at an inopportune time. Maybe time to do plugs, wires, cap and rotor and see what result that yields?
