Code p1105, hesitation, low idle, stalling, etc.

[jarero]

For about the past month my car (96 TSI AWD 5spd 84k) has been hesitating under boost intermitantly, a few days ago I got a check engine light (P1105, Fuel pressure solenoid) and this morning on my way to work a new problem developed. The car started and ran fine including a long warmup to defrost everything then when I got into traffic and at full temp I had to stop due to traffic and as soon as I pushed the clutch in the engine died. I started it back up and had to keep my foot on the gas to keep it running. When you are moving and in gear the car drives fine. From a search that I did about the fuel pressure solenoid it sounds like it is an unecessary part and that it could be removed from the car? If this is true could this be causing my low idle (400rpm) condition and stalling problem?

My car is stock except for the following:

9lb flywheel
ACT 2600
Dejon upper IC pipe with non-recirc BOV - I bought a recirculating BOV to replace the POS that came on the car when I bought it but haven't had a spare second to put it on.

Any help would be appreciated!

 

[jarero]

A quick update:

I just installed a recirculating BOV to try and eliminate that as a possibility and there was no change.

 

[spyderturbo007]

Try this:

http://www.dsmtuner.com/forums/showpost.php?p=1840502&postcount=3

 

[Doug99RS]

I've diagnosed and repaired a couple of these at work for the same fault code. Just put a new one on there and then clear the codes. Always fix what you KNOW is wrong and then go from there. Do not create more problems until you fully understand what you're eliminating or modifying.
Doug

 

[jarero]

Thanks for the advice. I have a friend with a matching car that I will swap in his good part and see if the problem goes away.

 

[TurboATM]

....i have a problem linked to this code, but i cant post a new thread...


about a week ago, i got in my car to come home from work and as soon as hit a little bit of boost, it backfires as if im hitting the rev limiter.

the car runs fine, just as long as i dont hit boost any more than the upper middle line on the boost gauge

(2g talon fwd, 14b turbo on stock boost, 2.5 catback exhaust with test pipe, act2100 and 8lb flywheel are only mods)

a local tuner shop hooked it up and got p1105 as the code, and that cvl. 1 is running lean, and htey told me it was most likely lean bc of the 1105 code. I tryed bypassing the sylenoid, cleaning the plug, and i changed the fuel pressure regulator.

before i go buy a new sylenoid (im talking about the black plug in/vacum line on the firewall, if im not naming it right) is this my problem????

 

[gsx219]

i also had the same problem where it would hesitate then at higher rpm the power kicks back in. so i started with the basics changed the plugs and wala that was the problem i was showing the same code but it fixed when i changed the plugs..

 

[TurboATM]

...should i change out the electric plug that runs the vacum lines?? is that a problem??

 

[synthetek]

The FPS is not necessary, I had a cel a while back for mine so I disconnected the FPS vacuum lines and looped a small piece of vac line to the 2 ports on the FPS, then run the line that used to go from the manifold to FPS directly to the regulator. I would try bypassing the FPS like I did and see if that helps.

Originally Posted by Taboo
1) The FPS closes the vacuum path to the FPR during start-up which keeps constant fuel pressure and prevents the fuel from evaporating in the rail when the engine is hot.
2) The only negative side effect is possible harder starting when the engine is hot. It might take just a bit more cranking, but once the engine starts the FPS opens in a matter of minutes and the fuel pressure is regulated by the vacuum/boost in the intake plenum. By-passing the FPS doesn't effect the drivebility of the car. If a bigger fuel pump is used, there are no noticable negative side effects even during start-up since the bigger fuel pump is able to provide enough fuel without its evaporation even when the engine is hot.

 

[TurboATM]

i have tried all of that. bypassing it by connecting the vacum line right to the regulator, unplugging the plug with the vacum lines on right, unplugged with it bypassed, it all changes nothing. Since it doesnt change anything to unplug it, im thinking it has gone bad. Is this the reason im having the problem of running so lean, and the backfiring when boost kicks in??

 

[TurboATM]

btw...how do i get a pic over on the left side where my info is on my posts like everyone else? i have spent 30 min trying to figure it out...

 

[synthetek]

i have tried all of that. bypassing it by connecting the vacum line right to the regulator, unplugging the plug with the vacum lines on right, unplugged with it bypassed, it all changes nothing. Since it doesnt change anything to unplug it, im thinking it has gone bad. Is this the reason im having the problem of running so lean, and the backfiring when boost kicks in??

If you bypass the FPS and it still dosent run right than you have another problem, replacing the FPS wont help.

 

[geesexxtsi]

Im havin the same problem under boost 98 gsx falls on its face i tested the fps and its good could it b the fuel pump?

 

[nightmares GS-T]

When I had this issue it turned out my o2 sensor was bad. Use a logger to see what its showing after its good and warm