Could my fuel injectors be leaking?

Burch98

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Oct 11, 2019
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Oklahoma
Okay I’ve done everything except the injectors. I think they are leaking causing a bunch of issues. Basically it takes several cranks to start, after awhile of driving it randomly acts like it’s flooding, then I have to pull over (won’t rev past 2k without sputtering) and it feels like I’ve lost power. You ask if I changed it/tested it I probably already have. TPS, CPS, MAP, fuel pump, o2 sensor, coolant temp sensor, spark plugs, wires, cap/rotor/pick up coil, vacuum lines. I need your opinion. It’s a 1998 4.0. I’ve even tried unplugging battery overnight.
 
If you tested the fuel pump what were the results, as your symptoms still point to the fuel pump in my mind.
 
If you tested the fuel pump what were the results, as your symptoms still point to the fuel pump in my mind.
sure have. Multiple times. Stays steady at +-49 psi. I ordered injectors already, some that were recommended on another thread that were remanufactured with good reviews. I’ve tried everything. I have cleaned the injectors before but from what I’ve read injectors cause these types of symptoms. It started when it was 100+ out and I was driving down the highway. Steadily getting worse. If the injectors don’t fix it then it’s going back home and I’m getting something different for awhile until I can just swap it with something more beefy anyways. It’s my daily, I can’t bring it to a shop necessarily for them to have it for a week. I started simple and worked my way around. No check engine light either. No pending codes. All I get is random OL-drive here and there along with insane amounts of fuel trim. Gets above +30%. I’m tired of messing with it. One last shot before the engine is getting thrown for some cash for an LS
 
Maybe a shot in the dark here but you said you replaced the o2 sensors...1. Did you use the NTK sensors 2. do you have any exhaust leaks at the manifold or manifold to pipe connection?
 
Maybe a shot in the dark here but you said you replaced the o2 sensors...1. Did you use the NTK sensors 2. do you have any exhaust leaks at the manifold or manifold to pipe connection?
Yes, ntk sensors were used. Getting accurate and good readings. Not that I’m aware of, I did have an exhaust leak but it was fixed. Also put a new exhaust manifold in around March
 
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Yes, ntk sensors were used. Getting accurate and good readings. Not that I’m aware of, I did have an exhaust leak but it was fixed. Also put a new exhaust manifold in around March
I'm having a similar issue with my 00 (non CA emissions), I have the new o2's , new fuel pump to put in still, and also need to tighten up the flange pipes. Probably going to tackle all that this weekend, I already did plugs So I'm hoping the rest address my drivability issues. If not I'll be scratching my head right along with you.

Something I just thought about with the 97 I had the cat broke into chunks internally and once it warmed up it would plug the exhaust when I tried to accelerate but it would idle fine. If I turned the engine off and restarted it it would clear up for a while. Eventually it sent enough chunks into the muffler and built up enough back pressure it blew the muffler off right behind the cat.???
 
I'm having a similar issue with my 00 (non CA emissions), I have the new o2's , new fuel pump to put in still, and also need to tighten up the flange pipes. Probably going to tackle all that this weekend, I already did plugs So I'm hoping the rest address my drivability issues. If not I'll be scratching my head right along with you.

Something I just thought about with the 97 I had the cat broke into chunks internally and once it warmed up it would plug the exhaust when I tried to accelerate but it would idle fine. If I turned the engine off and restarted it it would clear up for a while. Eventually it sent enough chunks into the muffler and built up enough back pressure it blew the muffler off right behind the cat.???
Yeah I’ve already inspected my cat to see. Might crack your distributor cap off and look at the connectors inside. Mine had 156k miles and were plum worn down
 
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You description sounds like a bad or intermittent sensor like the CPS. Since you've already replaced the sensors I'd look carefully at the wiring, especially the ground connections on the block and firewall and the harness near the rear of the valve cover. I've checked my injectors for leaks once, I just pulled them to see if they were wet. Intermittent injector problems seem to be related to their wiring.
 
Yeah I’ve already inspected my cat to see. Might crack your distributor cap off and look at the connectors inside. Mine had 156k miles and were plum worn down
My 2000 has the coil packs like the 01 and newer but the non CA emissions only has 2 o2 sensors like the 99 and prior.
 
You description sounds like a bad or intermittent sensor like the CPS. Since you've already replaced the sensors I'd look carefully at the wiring, especially the ground connections on the block and firewall and the harness near the rear of the valve cover. I've checked my injectors for leaks once, I just pulled them to see if they were wet. Intermittent injector problems seem to be related to their wiring.
The thing is it’s not even intermittent anymore. It’s just straight running like dog crap and getting miserable gas mileage right now. If these injectors don’t work it’s going back home and that’s what’s gonna happen, everything is being taken a part and cleaned
 
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My 2000 has the coil packs like the 01 and newer but the non CA emissions only has 2 o2 sensors like the 99 and prior.
Ohhhh I thought coil packs started for the wranglers in 01! My bad. It’s all trial and error and if you have a good multimeter then it’s a lot of testing lol it’s been doing it for a while but this past week has just been miserable, never been this bad before. Maybe it’s the cold weather, I don’t know.
 
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Ohhhh I thought coil packs started for the wranglers in 01! My bad. It’s all trial and error and if you have a good multimeter then it’s a lot of testing lol it’s been doing it for a while but this past week has just been miserable, never been this bad before. Maybe it’s the cold weather, I don’t know.
When was the last time you filled your fuel tank?
 
Are you able to watch fuel pressure while driving? Is there a fuel filter in the regulator?
 
Are you able to watch fuel pressure while driving? Is there a fuel filter in the regulator?
No sure if there is one in the regulator or not. It’s a delco pump. Pretty sure that’s what it was. Basically the same as the Bosch as far as what I could get. No one had Bosch anywhere