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Discussion Starter · #1 ·
I am experiencing an issue that I have never seen before... The first time I experienced this issue was after I had some new parts put in.
Here is what changed:
1 Transmission, and transfer case - They were sent out to Paramount Performance together. Bill repaired them and sent them back. I got an all new trans and transfercase and had it installed.
2. Stage 6 fuel hat
3. 30 tooth pulley
4. PT tuning Vacuum manifold. - This is what I thought was the culprit at first. But its not leaking, my gauges are working fine, and Im not loosing boost. All of my vacuum lines were replaced too.. So idk.
5. I got a new tune - But the only thing that changed in the tune was timing taken out and fuel added for the smaller pulley.

Apparently my tune is ok. I data logged it and sent it out to another tuner and he said theres nothing that looks very unusual in my tune. My original tuner said the same thing...

This is what my Jeep is doing:
when I start it up for the first time of the day I let it warm up and drive easy for about 15 mins until the coolant temp rises to about 190. Once it reaches normal operating temperature I start driving a little more aggressively.
All is good so far. If I stay out of boost and only drive slow all the time it will be ok, I wont see any TCM codes and it will not act up all. But once I start getting into boost things start to go wrong... The first few pulls in boost are PERFECT! The part throttle drivability is where it should be... But after about 10 pulls or so (sometimes it takes longer and sometimes shorter) it will go into "crappy driving mode" where I loose almost all part throttle boost drivability. I can put it in "5" at about 35mph and as soon as I accelerate to the point where the BOV closes and it hits part throttle boost the rpms will go from about 2,000 to 4,500 almost right away. And the Jeep will take off way harder than it should. If I keep messing around in "crappy driving mode" it will eventually throw a code. Which is a TCM code where it says I am locking up the converter.
When it does this I can only drive by staying out of boost or full throttle. If I dont hit full throttle than it will be in part throttle boost and the RPMs will jump so fast that it will make up to 3-4 psi without adding ANY fuel for it... This is not good for my stock block.:eek:
ANYTHING I try it just wants to do either no boost or full boost...

I called Bill and asked him about this code and he said it seems like a tuning issue and its throwing this code because the PCM is very confused. Well I have spoken to 2 tuners now and both say nothing looks unusual with my tune...

So what could be causing this? Does anyone have an idea?? After dumping so much money into my Jeep to fix problems, I am slammed with another problem.... I just want to enjoy driving my Jeep again.:boohoo:
 

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Discussion Starter · #3 ·
Check the map sensor?

go back to the old pulley and old tune and go from there to rule things out.
Wouldnt I get a code if the map sensor was acting up? How should I check it?

I will have to back track if I dont figure this out soon.. I am hoping for a simple fix because im unable to afford another repair that costs a thousand dollars again.
 

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Trinity, dashdaq, dashhawk or even better a scan tool (if you have a friend with one/cool shop) or replace it.

I would do the pulley and tune first though. Rule those out first.

How old is the battery? WK's are very very sensitive in their electronics
 

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2 MAP sensor is fine or else Johan would of found something wrong by looking at your logs , didn't the other tuner also look at the tune and said it looked normal ? Also Scam tune file remained the same in exception of timing and fuel being minimized . I am still having thoughts that your ESM is the issue as mine did the same thing you are describing and throwing a CEL U0404 ESM related .
 

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Discussion Starter · #8 ·
Trinity, dashdaq, dashhawk or even better a scan tool (if you have a friend with one/cool shop) or replace it.

I would do the pulley and tune first though. Rule those out first.

How old is the battery? WK's are very very sensitive in their electronics
My battery is good. Still new.. replaced it recently.

If I cant figure out anything else I will swap out the pulley and go back. Thats not a bad idea, and not very difficult to do.

What if your map sensor is 2 bar and your tune is written for 3 bar? MAP sensor is working just fine...
I dont know about that... I could look into it. But I didnt get a whole new tune. Just tweaked toe timing and fuel for a slightly smaller pulley.
 

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Was this immediately after you had the parts put in or a few days later?

I would also check all your vac lines and make sure everything is connected properly and nothing is pinched/blocked

Check the electrical connections to the trans and t-case (loose/dirty), input and output sensors too.
 

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Discussion Starter · #10 ·
Was this immediately after you had the parts put in or a few days later?

I would also check all your vac lines and make sure everything is connected properly and nothing is pinched/blocked

Check the electrical connections to the trans and t-case (loose/dirty), input and output sensors too.
Immediately after the parts were put in it started acting up.

I will look into this.. Im gonna try everything until I figure this out.
 

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I suspect the ESM as well , if not possibly bad o2 sensors... They are cheap and cost around 34 bucks each and would be a cheap fix for all 4 of them....
 

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Discussion Starter · #12 · (Edited)
I thought it was a bad ESM as well. But the TCM code I am getting is not that... It is TCM code P0741: Something to do with the Torque converter.

I am not seeing any PCM codes at all. And it drives ok sometimes. Thew other day I drove aggressively in boost a lot for over an hour and there were no issues at all. So it happens sometimes sooner, and other times it takes longer. Thats why I was thinking its a tuning issue. BuilderBill thought so also...


How could a bad 02 sensor cause a problem like that without throwing any codes?? :confused: If it is possible this could be the case than I will definitely check this out. I had cutout turn down tips put on during all of this also.. idk if that makes a difference.. My cutouts had already been installed a while back... I just had some turn-down tips put on while my Jeep was getting all that work done though.

Also I have noticed that the new transmission I got from Paramount Performance drives MUCH smoother than my last one. When I drive easy it shifts like stock again! Well.. 2-5 is like stock, 1st gear shifts still feel the same. My last transmission shifted much harder at all gears all the time. This is something else that I noticed right when I got my Jeep back... Along with this problem that I cant figure out.

Is there a possibility that something changing in the driveline could be confusing my tune? Maybe a different Valvebody or something??? Just trying to think outside of the box.
 

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Discussion Starter · #13 · (Edited)
I went back to Bwoody again today. Mike stopped what he was doing to help me figure this out. We checked the trans fluid level... Its perfect. Right where it should be. So that cant be the problem.

Then I got on the phone with Bill and tried to find out where to look next. He suggested that I swap out the MAP sensor.
We checked out me MAP sensor and found out that its a 2 bar MAP, so Mike ordered a new one.
So the next step is getting the 2bar MAP sensor and swapping that out with the old one to see if that makes a difference. If thats not the solution than both Mike and Bill told me they will make sure we figure this out. They wont leave me hanging on this.

Not very happy its still not settled. But I know its in good hands.

1 more thing. I drove for about an hour and a half today and the Jeep did not skip a beat. It drove perfectly.. no issues what so ever. I was driving hard also... :D So maybe tightening the BOV helped? IDK.. I keep saying that but then the very next time I drive the Jeep it goes into crappy driving mode again.


I also FINALLY saw my first WK2 SRT-8. It was Mikes Jeep. It already had a cold air intake hooked up, and an exhaust. It sounded good!!! That CAI is SICK! The air filter literally sits right in the lower grill. Its a cold air intake / Ram air intake in one! I thought that was pretty cool.
 
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