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Turbo Problem by StoneyRocket
Started on: 09-02-2013 04:25 PM
Replies: 7 (227 views)
Last post by: StoneyRocket on 09-04-2013 02:45 PM
StoneyRocket
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Report this Post09-02-2013 04:25 PM Click Here to See the Profile for StoneyRocketSend a Private Message to StoneyRocketEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well im back with another problems with my fiero i think i have somethings i want to check and try but before i do i want to see what other peoples suggestions as to why my car is running the way it is. Now since my accident i haven't drove my fiero i just has been sitting and i have been doing bodywork to it, but i did replace the old turbo i had on it with a new one the new one is oil cooled only instead of oil/water. Also my exhaust got stolen when i was in town but that's a different story lol. I have a couple of videos of my car running and here are is my problem when i drive it the car has no power seems like the turbo is doing all the work you can barley hear the motor and it is only running with a down pipe. I do have a broken off header bolt and it is leaking but with the old turbo it never seemed to make a dramatic difference also i think that my car is running lean i say this because when i tore the motor apart to install roller rockers and do the valves i had removed some spark plugs and i seen that the 1,3 cylinder that i pulled definitely looked like it was running lean. Nothing has changed from the old turbo setup to the new turbo i installed the only difference is that the down pipe bolt pattern was one bolt off from the last turbo they are both RHb5's and im pretty sure it has to have the same compressor maps so that shouldn't be the problem. If you want to help me just watch my videos and reply i am working a lot lately so i wont be able to work on it much. the knocking/ ticking thing is just my cat that pretty much blew out and he bolts ont he downpipe dont matter becuase its would be a boost leak since its my exhaust.
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Old Turbo
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Joseph Upson
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Report this Post09-02-2013 04:41 PM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post
First, you can not have missing or loose bolts from the exhaust manifold because it will have an adverse effect on your air fuel ratio causing incorrect fuel delivery. It must be repaired no exceptions or you can risk burning a valve among other things and that's likely why you are seeing the irregularity that you described.

One reason you have significant power loss is because all cylinders are not firing. I can hear a skip clearly in the video with the motor running. Fix the exhaust leak and check that you haven't crossed wires and for a bad ignition part, etc.

Just finished watching the whole video, that piece of pipe in your exhaust will kill any hopes you have of performance if you drove it that way.

[This message has been edited by Joseph Upson (edited 09-02-2013).]

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Slowbuild
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Report this Post09-02-2013 06:50 PM Click Here to See the Profile for SlowbuildSend a Private Message to SlowbuildEdit/Delete MessageReply w/QuoteDirect Link to This Post
Agreed.^^

Pull the spark plug wires one at a time to see which cylinder(s) are not firing. Check firing order if any of the wires have been disturbed.

I run open loop, so my a/f would not be affected, are open loop or closed with your setup? Wideband?

Anyway, misfire first, then on to more difficult stuff.

Chay
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Report this Post09-02-2013 07:09 PM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Slowbuild:
I run open loop, so my a/f would not be affected, are open loop or closed with your setup? Wideband?
Chay


Open loop means it will not be corrected for by the ECM, but if you are tuning based on AFR readings and you have an exhaust leak up stream of the wideband you'll be making changes in error.
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Slowbuild
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Report this Post09-03-2013 01:20 AM Click Here to See the Profile for SlowbuildSend a Private Message to SlowbuildEdit/Delete MessageReply w/QuoteDirect Link to This Post
True if he made any changes. If he's open loop and hasn't made changes there should be no reason to go lean all of a sudden, was my point.

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Joseph Upson
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Report this Post09-03-2013 07:01 AM Click Here to See the Profile for Joseph UpsonSend a Private Message to Joseph UpsonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Slowbuild:
True if he made any changes. If he's open loop and hasn't made changes there should be no reason to go lean all of a sudden, was my point.
Chay


I run closed loop but in the past before I learned to reign in idle, I used open loop but never thought about the fact that exhaust leaks wouldn't affect the tune, they were always bad in my mind. On the other hand, that missing bolt from the manifold easily seen in the video appears to also have a damaged gasket underneath and although it will not affect the tune if in open loop, it will leak a massive amount of heat energy under boost that is certain to cause loss in power and he seems to be a little too comfortable with it.

I bet that stock manifold is warped to as a result of uneven bolt torque (or missing). There was power he never saw as a result with the old turbo to realize just how much of an effect on potential it has. The turbo sounding like it's doing all the work is probably the exhaust leak he's hearing.

[This message has been edited by Joseph Upson (edited 09-04-2013).]

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StoneyRocket
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Report this Post09-03-2013 03:53 PM Click Here to See the Profile for StoneyRocketSend a Private Message to StoneyRocketEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well i only worked a half a day today so i decided to go out and work on my fiero now Joseph i know that the exhaust leak is going to affect my performance but from what i was felling in the video was indeed because the cat hole was plugged and the exhaust wasn't escaping and was flowing back up the down pipe. Which in turn enhances the exhaust leak. My gasket was fine i can still reuse it, i have removed my headers and extracted the bolt and will re-install it tomorrow on my day off with new bolts and im going to knock out the cat completely so when i do get around to installing my new exhaust i wont have to worry about any blockage. Think im also going to slap a timing light on it and see how the timing is set its been a while. Soon i will put on my new dynomax race bullets should give it a nice growl. But tomorrow i will see how the car runs and post a video of the progress. Thanks for your input always welcome.

Edit, I forgot to put that i dont think my motor is misfiring i think its my O2 sensor since its throwing a code im pretty sure that any A/F problems or misfires are linked to that i installed one that i think is good it had the plastic on the tip and i didnt test it but i will reset my codes tomorrow before i start it and see whats up.

[This message has been edited by StoneyRocket (edited 09-03-2013).]

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StoneyRocket
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Report this Post09-04-2013 02:45 PM Click Here to See the Profile for StoneyRocketSend a Private Message to StoneyRocketEdit/Delete MessageReply w/QuoteDirect Link to This Post
Im back again with the header fixed and a new oxygen sensor fixed. I drove it and took a video but then it started to run bad anyways long story short my plug wires on the back side decided to lay on my headers and it burnt a hole in #2,4, that's where u got the misfire Joesph. But here is the last video of my car and i do believe that everything is running right feels like it did before i was in a wreck.
Fiero Fixed
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