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Help! No power after boost, off throttle...

6K views 39 replies 12 participants last post by  gerd35 
#1 · (Edited)
Hey, I'm posting this for a very close friend of mine, he's not on the forum. But need some help to narrow this problem.

He has a 76mm turbo kit, 400 fuel pump, 80cc injectors, built 6.1- 9.5 forged and heads....
Dyno tuned with a 9lbs spring..
This problem comes and goes, but can't comfortably drive it. So he just has it parked for most..
It runs fine doing a wot blast, till he let's off the throttle!
Or runs fine cruising around till it spools and he let's off gas! Its like limp mode, no power, no throttle response, just stumbles and flutters.... AFR drops down to around 10... Last about 15 sec, then every thing is back to normal! Wtf?
Any help, ideas, advice will greatly appreciated! Thanks
 
#18 ·
Mine has done this to when I first put the super charger on. It's for sure in the tune.
I'll echo again, it is a tune issue
Yeah D, still having issues..... Different issues, but issues!!

Mango Bill knows his stuff when it comes to our rigs. I highly recommend his work as do many others. People have to realize there will always be "growing pains" with any build.

Now with Tony's "issue" all roads lead to OZ or in this case the TUNE!
 
#5 ·
Is he running a Stock throttle body or a bigger size throttle body? Any codes?
 
#8 ·
Knuckles, it's a stock throttle body bro......

He got a revision earlier, so we went for a ride to do a log and it did it again!
This time with 5' flames out back!!! Had to quickly pull over, truck sliding in grass and jump out the jeep running! Lmao! Funny now, cause all is fine and no damage is done... But oh boy, should have seen us heading for the hills!
It drove back fine and will stay parked till he gets a new tuner and starts from scratch!!
 
#9 ·
Oh ok cool.. Dayuuumm bro that's some scarey shit!!! Keep us posted man..
 
#13 ·
Ok guys lets back this up a minute! Tony's jeep consist of Demon Performance 76mm Turbo kit , it was originally installed ( by me ) on a stock 6.1 Srt8 Jeep when installed it was setup with the stock 6psi spring on the waste gate ( red if i believe ) it had peaked as far as 8psi and low as 6.2. he drove it for about an month ( think there may have been 1 revision since dyno tune Tony can verify ) after driving it for a month he was developing serious blow by, the ring lands on #!#3 and #7 were broke. Tony purchased a 6.1 from Inertia Motorsports with forged and arp studded internals we reworked the heads as well, 2618 pistons with 9.5 compression we installed the new setup with the original wastegate spring, got a start up tune drove it and datalogged for tuner, no issues ran like a champ pulled like a beast ! once at the the dyno it had baseline of 515/525 rwhp the spring was changed out for the 9.x psi ( green ) so i was told it then produced 615+ rwhp, Tony communicated on way back from dyno tune that is was acting like a Limp mode issue ? same symptoms as listed, under boost letting off throttle there would be no response from peddle ..He brought the Jeep to me and I started investigating could find no evidence of LIMP Mode stored with in the PCM/TCM and I personally could not replicate the issue ( does not mean it did not happen) the only issue that presented itself was P0111 - Intake Air Temperature Circuit Range/Performance Problem, Thouroughly checked the circuit and wiring replaced the sensor problem fixed ( or atleast no issue of this issue arising again) he then proceeded to get code P0205 - Injector Circuit Malfunction - Cylinder 5 this code appeared twice- diag. wiring and injector could not replicate issue nor found one, upon input from Tony we where instructed to replace throttle body ( the tune now has been modified/tweaked from another tuner ) replaced TB calibrated it and test drove it , drove it like grandma and beated on it like a red headed step child ..performed like a beast ! boost peaked as far as 11+ and AFR was in the 11.x real quick stops or multiple throttling of pedal resulting in 10.5+ ocassionally dropping to 10.0 , found no issues ran Great ..Tony left and was going to datalog and take for test drive ..Now we are at the present as i have not talked to Tony in-regards to "Flames" shooting out tailpipe not sure whats going on at this moment , will investigate in a.m.
 
#15 ·
You seem to leave out the incident of the wastegate being routed incorrectly causing the charge pipe to blow off. This could be the issue he was running into with P0205 code.

He has had a very difficult road due to some tuning issues and install issues. So the issued he has brought to my attention are 100% tune related... ghost throttle, super fat AFR.. The only thing a tune won't necessarily correct is the limp mode. He's running on a stock tranny making 600+whp/tq... He can expect limp mode which won't be stored in the computer all the time.
 
#25 ·
Once again, I will type my phone number so this thread can go back on track to assist tony in resolving his ghost acceleration and limp mode issues.

331.999.4999.

I just got off the phone with Tony about an hour ago. Too funny how I never talk to the guy yet we just had an interesting convo. Have a good night and see you at ATCO
 
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#27 ·
Haha benefits of working at ATT for 5 years. Had a few tricks up my sleeve. Thought it was easy to remember myself.
 
#31 ·
Damn....just someone get Tony back on the road so we can be out & about when the weather clears up! The poor guy missed out on all the amazing meets tons of us hit up all summer. Speaking from my own interaction with him here locally, Bill J is a str8 shootin stand up guy, a freakin beast at what he does and knows more sh!t about our rigs in his sleep than many who claim expertise out there.
 
#32 ·
Kazaam, appreciate the support, I have reached out to Jeremy , I know this post originally started as an inquiry and ended up as pissing match between me and Jeremy ( I got lost in the post so thank you all for putting post back on track), I am now conceding, My main goal is to get Tony up and going ( as stated earlier by Jeremy) , as i stated earlier , Tony has acquired 2 of the best tuners ( not mentioning names as it is not my place) with myself/Jeremy/Tuners along with there direction we will resolve this issue! as stated in previous post Jeremy posted his number ..I will now post my number ( you all already have my address so scrapple and eggs still apply) any and all involved please feel free to contact me call/text @ anytime 240 216 7452 .....
 
#34 ·
Mr Mango Bill. i am interested in purchasing that camouflaged Jeep you have in your driveway. how much are you asking?

i can attest to Bills expertise with our rigs. he knows his stuff and never tries to screw anyone over. imho, best lx mechanic in our area.

glad the hatchet is buried.
 
#36 ·
Ok Guys and Gals been couple weeks since update on Tony's Jeep , now I may be premature not too mention putting hex on it ..but none the less here I go ..lol , so as most of you know we have had a plethora of issues and assuming it was tune/turbo issues well at this point it was neither. Just a quick relapse of whats been going on since install of the new motor and turbo kit.... After install of new motor an turbo system it was off to the dyno for tuning everything went good and was running awesome on the dyno , after leaving dyno Tony was experiencing an issue when letting off throttle and going limp now whether it was limp mode or not still remains a mystery as no codes indicating limp mode , once Tony made it back to the shop he relayed the issue to me ...I scanned the system and found code for the IAT sensor I then proceeded to trace wires and even re soldered them and replaced sensor ( the turbo kit requires you to install/solder/heat shrink IAT sensor as it is screw in type for the piping) this was the second one we replaced since original install. ran the jeep everything seemed fine no issues...approx. few days later Tony called and said it is acting up again ..Im like WTF? so he brought it by scanned system and now we have have map sensor issue ..again traced wires check all connections conclusion was to replace map sensor...again everything was good no issues and no codes.

Now in the meantime Tony started experiencing the assumed limp mode issue is was spuratic and stating it was dropping to 10.0 on afr and had no throttle response we all assumed TUNE issues and he had acquired the services of the 3 best tuners around and after numerous revisions/logs some things had seemed to get better but was still experiencing the assumed limp modes issues ..not too mention the flames out the tail pipe issue ..now why all this was going on we started seeing codes p0205/206/208 now these codes where also spuratic but they did come back on a regular basis.

So on 11/16 or the 17th had Tony drop off the Jeep and leave it with me , I was sure we had an electrical issue at this point at least with p02xx codes , even though in the past I traced wires within the harness with no avail , I spoken to tuner and Jeremy and was like what am I missing ? me and Jeremy talked for about 30 min or so and communicated to him I ohmed out injectors traced wires checked sensors ..Im not seeing anything ..but we both agreed it had to be a voltage issue , if you think back we went through map sensor/Iat sensors/TB ( forgot too mention that) and now possible injector/PCM issue ...I was like no way this cant be happening ..so I once again went over system swapped around injectors for the cylinders we where having apparent issue with to see if it would follow also re routed PVC system to vent to atmosphere...then by chance I looked over at the battery ( neg terminal) and noticed some corrosion then upon further investigation ..this is what I found






So replaced terminal .... it has now been 48 hrs ( this is the longest this jeep has ran with no issues) and no issues no codes/limp mode nothing even had Tony come here and drive it for the last 2 days and he could not replicate the issue at all !! Can it be all these issues were caused by a $2.45 part ..it appears SO !
 
#37 ·
I've seen crazier things happen man. These Jeeps are very picky when it comes to voltage. I've seen it all.
 
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#38 ·
I definitely can believe it as I have seen weird things happen especially with a corroded terminal and if it has that white powder on it as well. Keep up posted man...
 
#39 ·
Nice talking to you bill.

Glad to see our discussion lead to something. Thanks for putting in the effort to help tony get back on the road. Sounds like we are on to something.
 
#40 ·
Nice work Bill! Its amazing a $9 piece could cause so much trouble......
 
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