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Discussion Starter #1 (Edited)
Okay I don't know what to do. My mechanic almost has my install finished. I have a bone stock 2008 Jeep SRT8 with a Vortech V3 kit with 180 stat and 1 step colder plugs and the blower still has the stock 32 gear pully in it untouched.

Here is what's wrong. It's pulling a code he says which I believe is a lean code like p2096 or something and I know there is an exhaust leak because I used that shitty exhaust bung clamp thing and of course it won't work on our stock exhaust. That I can fix at an exhaust shop, so I'm not freaking out about that but the real issue is my mechanic just told me he is seeing as high as THIRTEEN LBS OF BOOST and 8lbs under very little throttle!!!!
WHAT??????????????

Obviously I'm concerned as it is WAY higher than it should be. Then I thought, how can it boost this high at all? Then I thought about how he ran the boost gauge....
It's an Autometer gauge "cobalt" digital and in the kit they never included a "T" fitting that would fit the brake booster line so he used the smaller vacuum line off of the drivers side intake manifold close to the evap stuff. Is that bad? All the vacuum lines are tied in there. Can someone please help??? I am so screwed and totally regretting this kit now, I've been without the Jeep for 3 1/2 weeks now and it looks to be A LOT more now and I'm running out of $$$$$$$$$$$$.

HELP HELP HELP PLEASE!

Can the exhaust leak cause any of this? Is it the vacuum source? What's wrong?????????
 

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Okay I don't know what to do. My mechanic almost has my install finished. I have a bone stock 2008 Jeep SRT8 with a Vortech V3 kit with 180 stat and 1 step colder plugs and the blower still has the stock 32 gear pully in it untouched.

Here is what's wrong. It's pulling a code he says which I believe is a lean code like p2096 or something and I know there is an exhaust leak because I used that shitty exhaust bung clamp thing and of course it won't work on our stock exhaust. That I can fix at an exhaust shop, so I'm not freaking out about that but the real issue is my mechanic just told me he is seeing as high as THIRTEEN LBS OF BOOST and 8lbs under very little throttle!!!!
WHAT??????????????


Obviously I'm concerned as it is WAY higher than it should be. Then I thought, how can it boost this high at all? Then I thought about how he ran the boost gauge....
It's an Autometer gauge "cobalt" digital and in the kit they never included a "T" fitting that would fit the brake booster line so he used the smaller vacuum line off of the drivers side intake manifold close to the evap stuff. Is that bad? All the vacuum lines are tied in there. Can someone please help??? I am so screweda dn totally regretting this kit now, I've been without the Jep for 3 1/2 weeks now and it looks to be A LOT more now and I'm out of $$$$$$$$$$$$.

HELP HELP HELP PLEASE!

Can the exhaust leak cause any of this? Is it the vacuum sourse? What's wrong?????????
Bold statement ( Impossible) First what tune you are running ? and what are you using predator or trinity ..
 

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I would check and varify the gauge is working right first.

Newfie.
 

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I installed my vortech in 8-9 hours. What tune do you have? On the Booster Vacume line,I had to make a Brass T fitting with a smaller port for the BOV & I put another little T in that BOV hose to go to my Boost Guage.
 

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Oh and for the record , don't expect to not have issues etc , I got stuck almost two weeks do to a bad 2 bar map sensor till we figure out .. Power comes pricey and with issues we all have to face ... I'm having fuel issues at the moment .
 

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Discussion Starter #6 (Edited)
Bold statement ( Impossible) First what tune you are running ? and what are you using predator or trinity ..

No tuning yet I just have the basic vortech tune from MD Speed - Modular Depot just to get it started and working but 13lbs? Jesus. Using a Predator BTW and I'm not even near it right now.
 

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Discussion Starter #7 (Edited)
Oh and for the record , don't expect to not have issues etc , I got stuck almost two weeks do to a bad 2 bar map sensor till we figure out .. Power comes pricey and with issues we all have to face ... I'm having fuel issues at the moment .

Oh man, I know, I hear ya. My SRT-4 is currently screwed too which makes this all the more totally frustrating, it has a serious issue too that came up just a couple days ago. I have been in the game since 98' and have done major mods to a couple other cars already BUT when you put on a bolt on "kit" on a bone stock vehicle? Come on man..... yes hiccups, expenses that were unexpected? sure, but this? overboost on this kit? What? The gauge is super expensive and high quality, crazy if it's $hit right out of the box, I guess it's not impossible but absolutely unlikely at least.

So can anyone verify if an exhaust leak can cause these issues or if that vacuum line is wrong for the setup? Also is it impossible to hit that kind of boost? What can cause it? I know the tune is nowhere near started really they just calibrated it for the vortech kit set up, then I datalog and give them the logs.....BUT with boost readings like that? and an exhaust leak, there is no point yet. My mechanic is out of ideas he can't figure why the guage would read like that.

Man what a bummer.
Thanks for the help either way
 

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Do some datalogging and look at your MAP sensor and see what it says.
 

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Discussion Starter #9
Do some datalogging and look at your MAP sensor and see what it says.
Okay here is the scoop thus far:
The code throwing is
P0174

The map sensor is reading hg or ed or whatever it is (mercury) around 20 and the boost gauge is reading it around 5 or so. How does that happen? That's got to be an issue, he thinks the map sensor is bad or something

Secondly the Jeep runs worse after it idles down, it then runs like crap and reeks of fuel. Plus I think that code is all about fuel isn't it? I'm running a Kenne Bell BAP with the stock pump.

My guy also said the boost gauge pins didn't line up either with the socket and he had to move them a bit to get them to line up but I'm sure he didn't damage anything on the gauge.

How can I datalog like that though, isn't is dangerous? I have no access to the Jeep right now and he is done for the day and has next to zero time to work on it now. He said he can do "a little" this weekend lol and he has 4 days in a row off. I haven't had a holiday in over a year.....damn I wish he'd throw me a bone here but he's fed up too after this massive amount of time spent.
 

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Discussion Starter #11
Exactly what i was going to ask him ,don't even need to turn on the car
Really no need to even let it run? How will we figure out what's making it run so poorly? That's strange. Can you tell me what settings to datalog?
Thank you.
 

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You subtract 14.7 from the MAP reading if you're close to sea level if not you'll have to do the BARO conversion ordeal. WINK knows all about that. I'm at sea level so I don't have to worry about that. So that puts you right at 5 psi about.

Here you go.....

http://www.cherokeesrt8.com/forums/showthread.php?t=38707
 

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I havent heard any talk of air fuel ratio #'s? I would put less stock into the boost pressure, since it is mechanically limited and pay attention to fuel / pressure.

It is totally possible your getting too much fuel in the tune for whatever reason, and could be many. I am no expert by any means, but I went through hell with my vortech install , and it actually took nearly 1 1/2 months of multiple trips back to the installer, many posts here, and ultimately taking it to one of the best shops in the country to get the problems ironed out. I dont even want to tell you what the final total for my install costed me after all said and done!

Keep at it, once you get things dialed in, you'll forget all about the problems you had :D
 

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True that , took my installer 2 days to bang it out ...
 

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Up in Edmonton you should be making about a pound less than the same guys running a similar system at sea level.

To calculate your boost using the Predator, capture both the barometric pressure and your manifold air pressure. Once you've got that you'll need to convert the barometric pressure from inches hg into psi (http://www.engineeringtoolbox.com/pressure-units-converter-d_569.html) then subtract your barometric pressure from your manifold air pressure to get your boost.
 

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Discussion Starter #18
Who is installing the kit? 3.5 weeks to install a Vortech? Thats a 2 day job max.
My buddy he's a journeyman and has lots of experience with turbos though not blowers....
Anyway the 3.5 weeks is prob only about 16 hours total.... But he has limited time obviously. Yeah I know I should have gotten a pro and just paid double and had it done right.
 

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Discussion Starter #19
You subtract 14.7 from the MAP reading if you're close to sea level if not you'll have to do the BARO conversion ordeal. WINK knows all about that. I'm at sea level so I don't have to worry about that. So that puts you right at 5 psi about.

Here you go.....

http://www.cherokeesrt8.com/forums/showthread.php?t=38707
Wow that's great news! I'm sure it's the raw tune then, so you can adjust it on the predator or how do you do it? Surely that will make it display correctly right? I mean you don't mean to have to do math everytime you look AF the gauge obviously right?
Ok so the million dollar question how do you calibrate it? My AEM uego gauge didn't need calibrating and read very well.... Weird this one is a much better unit and that would also make my boost display WAY higher than it should too?
Thanks!
 

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Wow that's great news! I'm sure it's the raw tune then, so you can adjust it on the predator or how do you do it? Surely that will make it display correctly right? I mean you don't mean to have to do math everytime you look AF the gauge obviously right?
Ok so the million dollar question how do you calibrate it? My AEM uego gauge didn't need calibrating and read very well.... Weird this one is a much better unit and that would also make my boost display WAY higher than it should too?
Thanks!

It isn't a matter of tune. And it isn't the A/F gauge (air/fuel). Harrison was talking about boost, not air fuel mixture.

The map sensor measures absolute pressure. Meaning it also reads the atmosphere's pressure at the same time. So the 14.7psi is the pressure the atmosphere is 'producing' because of gravity. Regular boost gauges/vacuum gauges are set to zero at atmosphere and then shows you boost and vacuum from that point.

There may be a way to configure a custom PID in the Predator so you can datalog to read 0 at atmosphere. Otherwise just subtract the atmosphere pressure from your reading. YYCSRT8 gave a more precise way of doing it above. Maybe there is a way to program that into the DataViewer software as a custom PID as I said.


And/or get a real boost gauge.
 
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