I’m going broke and insane (and need help diagnosing my Jeep)

Joined
May 7, 2022
Messages
28
Location
Montana
2011 Jeep rubicon unlimited with Ripp supercharger.
After getting new transmission, I can’t go full throttle. It starts stumbling like it’s starving for fuel or ignition. Half throttle it runs and shifts perfect. I’ve had two shops test drive it with a laptop hooked up and all systems are working properly. No codes.
Things I’ve tried to fix it…
Compression check. All cylinders are 180-178 psi.
Radiator pressure check. Stayed at 18lbs with no drop.
Swapped out coil pack.
Swapped out throttle body.
Replaced plugs/wires.
Replaced every sensor. Cam,crank,map,knock,intake air temp. Still nothing.
Replaced the fuel pump. And have fresh 92 octane gas.
Updated Diablo tuner and re flashed.
O2 sensors are communicating properly.
Any ideas what can be causing this?
 
Have you checked to se if the underhood insulation is covering the air intake? Has happened at least 3 times on this Forum in the last 2 years.

P2174: Sudden Low Airflow Detected | Jeep Wrangler JK Forum
This. You put your foot in it and the supercharger pulls as much suction as a vacuum cleaner.
Does the engine react the same way when sitting in park? If you rev it while in park does it do the same thing?
Maybe take the hood off and run it down the road and see what happens?
 
The way the supercharger air filter is sitting, it seems impossible for the insulation to be causing this.

Have you checked the fuel pressure? Just because you replaced the fuel pump doesn't mean it's getting the correct PSI.

There should be a regulator somewhere anyway most Fuel injected engines have always had one.
 
This. You put your foot in it and the supercharger pulls as much suction as a vacuum cleaner.
Does the engine react the same way when sitting in park? If you rev it while in park does it do the same thing?
Maybe take the hood off and run it down the road and see what
Have you checked the fuel pressure? Just because you replaced the fuel pump doesn't mean it's getting the correct PSI.

There should be a regulator somewhere anyway most Fuel injected engines have always had one.
I had two shops go over every. I was told it had good pressure. But maybe the volume wasn’t there. That’s why o dropped the tank and installed a new pump. I’m not get any lean codes. Or any codes at all.
 
I had two shops go over every. I was told it had good pressure. But maybe the volume wasn’t there. That’s why o dropped the tank and installed a new pump. I’m not get any lean codes. Or any codes at all.

When it starts stumbling do you let off it or do you keep your foot in it? If you let out of it maybe it's not happening long enough for it to get a code. I

It sounds like a fuel or air problem to me.
 
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When it starts stumbling do you let off it or do you keep your foot in it? If you let out of it maybe it's not happening long enough for it to get a code. I

It sounds like a fuel or air problem to me.
I let off if I can. If I’m going up a hill I need to stay in it. It feels like it’s starving for fuel or the ignition is cutting out.
 
Again, is it "stumbling" when it's in gear, or does it happen while in park/neutral as well?
And, if it occurs while it's in park/neutral, try opening the hood and see what happens.
 
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I let off if I can. If I’m going up a hill I need to stay in it. It feels like it’s starving for fuel or the ignition is cutting out.

If it was electronic problem the CEL would be light up. When they were Mapping it when it did it nothing was showing up as a problem?

Can you manually drop down a gear with your trans if it starts doing it so you can see what happens?
 
If it was electronic problem the CEL would be light up. When they were Mapping it when it did it nothing was showing up as a problem?

Can you manually drop down a gear with your trans if it starts doing it so you can see what happens?
Spartans Tuning and J&K customs couldn’t find one single thing pop up while mapping it. They assumed it had bad gas. If I drop a gear and floor it, it falls on its face and stumbles. If I’m light on the throttle, it pulls and boosts all the way up to 90mph
 
Spartans Tuning and J&K customs couldn’t find one single thing pop up while mapping it. They assumed it had bad gas. If I drop a gear and floor it, it falls on its face and stumbles. If I’m light on the throttle, it pulls and boosts all the way up to 90mph

Right there is telling me fuel or air.

Have you recently checked your speedometer calibration with a GPS to verify that it's still reasonably close?
 
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Right there is telling me fuel or air.

Have you recently checked your speedometer calibration with a GPS to verify that it's still reasonably close?
I haven’t. But a couple people mentioned that maybe the tranny shop “flashed” the transmission wrong. They said it’s impossible tho. I know they flashed something to it because my tuner thought it was a different vehicle. I had to call Diablo to reset the tuner.
 
I haven’t. But a couple people mentioned that maybe the tranny shop “flashed” the transmission wrong. They said it’s impossible tho. I know they flashed something to it because my tuner thought it was a different vehicle. I had to call Diablo to reset the tuner.
But it definitely feels like it’s not getting enough gas or the timing is off or something. I just don’t understand why there’s no codes.
 
I haven’t. But a couple people mentioned that maybe the tranny shop “flashed” the transmission wrong. They said it’s impossible tho. I know they flashed something to it because my tuner thought it was a different vehicle. I had to call Diablo to reset the tuner.

Also when they put the new trans in I hope they put a new torque converter in also. Maybe it could have been that your old converter was slipping because of the extra HP and that was letting the engine pull through it before. Now with a new tight torque converter it's not slipping like the old one.

Have you talked to the trans shop about the issue and what you've done?
 
Also when they put the new trans in I hope they put a new torque converter in also. Maybe it could have been that your old converter was slipping because of the extra HP and that was letting the engine pull through it before. Now with a new tight torque converter it's not slipping like the old one.

Have you talked to the trans shop about the issue and what you've done?
Yes. They’re saying it’s the engine not the transmission. They said the torque converter was slipping tho