couple issues need help please

1991eagleawd · Sep 17, 2011

ok, i have a 1991 tsi, 195 FP, 550 INJ, fmic, type rs bov recirc(atompheric right now due to no hose). still same issue with or without recirc. big 16 g. wide band, safc2, turbo xs MBC.

ISSUE 1- when i start up when cold, warm, anytime when not running temp.....
it surges. when cold it will idle perfect at 2000rpm. from what ive read this is normal for talons to warm up.....then drop down to 1000 and start surging from 1000 to 1500 till running temp. when warm it just surges the same till running temp. boost leak test.....i know. but till then maybe i can get some ideas of what it might be? i did all the fmic myself, its tighter than a nun. so i dout it is thats. i put on a new turbo, wastegate and housing...all tight. and this problem has been occurring since day one. the SURGE. i have yet to takr the intake mani off and check that. thought i would ask you guys first before that.

ISSUE 2- i could only ever build 10 psi. figured it was a boost leak. found it, wastegate housing was cracked. replaced it, building more boost now. :hellyeah:

BUT, yep but it seems like when i hit 15psi there is a fuel cut or something? just hits a wall and then picks up a split second later when i get off the throttle.
i noticed that when i get over 10 psi the wideband reads around 10.5. seems rich to me. and this is around 3000-5500 rpms. please correct me if im wrong. but the safc2 controls the air/fuel mixture. and by minusing ...lets say 4000rpms on my safc2 its making it leaner. there is a hi and low. high is set @ 80% low @ 30%. so when im 80% throttle thats high settings on the sacf2.

so....noticing this richness at high throttle i adjusted it to minus 30 across the board in the high sttings...

still rich at high throttle....??

any ideas? issue 2 is of more importance cause i want to hammer down 20 psi and know im not going to hit that wall and F something up....

thanks for taking an hour to read this, any help is a step in the right direction. so thanks to all in advance

AlaskanDsm · Sep 17, 2011

I am unsure about anything to do with the SAFC settings.

But as far as the surging goes, it could be anything from a boost leak to something like your ISC going bad.

Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

If you know that you should do a BLT, then you should go ahead and jump on that. It may not be your intercooler pipes but it could be some of the rubber hoses or the TB shaft seals. do a full BLT and just be very thorough. I am sure there is something that needs to be sealed up.

1991eagleawd · Sep 17, 2011

AlaskanDsm said:
I am unsure about anything to do with the SAFC settings.

But as far as the surging goes, it could be anything from a boost leak to something like your ISC going bad.

Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

If you know that you should do a BLT, then you should go ahead and jump on that. It may not be your intercooler pipes but it could be some of the rubber hoses or the TB shaft seals. do a full BLT and just be very thorough. I am sure there is something that needs to be sealed up.

I'm sure there is a leak on the throttle side. Just thought there might be a common issues that this might point to? I did notice that there is a box on the fire wall under the throttle cable "box". There is a vacuum line going to this box under the throttle cable "box". Looks like that vacuum nipple was broke off at one point and the owner glued it back on.
1st. What is this box? And would this causey problem?

I read over Terry's article. Very informative. But my surge goes away when running temp is reached.

AlaskanDsm · Sep 17, 2011

Your surge goes away as does mine when operating temp has been reached. This is because your car no longer has to be in the warm-up cycle that the engine goes through to reach operating temp. If I can recall correctly, the reason that you get idle surge is because the ISC attempts to adjust the amount of air flowing into the TB and once it maxes out the "steps" of how it adjusts, it resets and tries again therefor causing your idle surge. Even a small leak can cause idle surges.

As far as the throttle cable box, it sounds as if this is the vacuum control for the cruise control. Normally there is a rubber hose that travels from that box to a vacuum motor on the divers side of the vehicle, just behind the strut tower area. I could be mistaken but that is what it sounds like. This would not cause a leak in the intake system as I do believe that they are not connected.

1991eagleawd · Sep 18, 2011

where exactly is the isc? sorry for the noob questions. and can i repair the existing isc?

zanderson · Sep 18, 2011

Its the idle speed controller. It purpose is to help maintain a good idle. Its located on the throttle body.

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zanderson · Sep 18, 2011

I would do a boost leak test and read on the vfaq how to test your ISC and MAF.

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AlaskanDsm · Sep 18, 2011

1991eagleawd said:
where exactly is the isc? sorry for the noob questions. and can i repair the existing isc?

I get off work in 30 minutes and then I can try and get you more info about the ISC. Don't just assume that the ISC is the problemn when the innitial cause could be boost leask from any number of areas in the intake system. Also, the ISC may not be the cause, but it could be the FIAV in the TB that is messed up. A new ISC is more expensive than spending a couple hours with really soapy water and your BLT and going over every inch of your intake system and vacuum lines. you may be surprised at what you find. Also another tip is to pressurize the system to slightly more than the boost you are running to make sure that you are not leaking when you are at full boost.

Also, I do not believe that at this time that there is anyway to rebuild or to fix the ISC but I could be mistaken. When I had to replace mine, I looked for information about fixing it but I never came across anything.

To give you a somewhat direction of your ISC, it is a 6-pin connector on the back passenger side of the TB. It is somewhat low on the TB so you just have to look around for the connector. I will try to find the dynamic link on here to things in the engine bay otherwise I will post up a picture.

I cannot find the site so if someone else could link to that site of the virtual tour of the engine bay, that would be awesome!! Thanks.

1991eagleawd · Sep 19, 2011

AlaskanDsm said:
I get off work in 30 minutes and then I can try and get you more info about the ISC. Don't just assume that the ISC is the problemn when the innitial cause could be boost leask from any number of areas in the intake system. Also, the ISC may not be the cause, but it could be the FIAV in the TB that is messed up. A new ISC is more expensive than spending a couple hours with really soapy water and your BLT and going over every inch of your intake system and vacuum lines. you may be surprised at what you find. Also another tip is to pressurize the system to slightly more than the boost you are running to make sure that you are not leaking when you are at full boost.

Also, I do not believe that at this time that there is anyway to rebuild or to fix the ISC but I could be mistaken. When I had to replace mine, I looked for information about fixing it but I never came across anything.

To give you a somewhat direction of your ISC, it is a 6-pin connector on the back passenger side of the TB. It is somewhat low on the TB so you just have to look around for the connector. I will try to find the dynamic link on here to things in the engine bay otherwise I will post up a picture.

I cannot find the site so if someone else could link to that site of the virtual tour of the engine bay, that would be awesome!! Thanks.

Boost leak coming soon.
If it matters.....? The boost holds steady when in boost. which leads to my next question......
Why am I hitting a wall at wot? This is my major concern. I can live with the surge for now. Can someone help me on this one?

Please guys. Im in northern ontario, the snow is coming soon and i havent really tested her. And when I do, it hits that wall.....? Please, any ideas is greatly appriciated

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couple issues need help please

1991eagleawd

AlaskanDsm

1991eagleawd

AlaskanDsm

1991eagleawd

zanderson

zanderson

AlaskanDsm

1991eagleawd

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