So heres the exact problem with my car.

I was having a hard time to get it started for a day.

I finally got the car started and when it was parked it was idling good and reving fine.

I go to put the car in first gear and start to slowly release the clutch and the car starts to bog on me, i then take it out of gear and start to pedal the gas and it got back up to idling fine.

I then go to put it in reverse and it does the same thing.

If I dont take the car out of gear it will shut off on me, even before i fully disengage the clutch.

It starts randomly when it wants and when it does start the same symptoms happen.

any suggestions on what i should do?

 

As it's bogging, is the car moving at all? Will it start to roll? Make sure nothing in your drivetrain is broken/binding/frozen that would keep the thing from rolling.

 

it rolls fine

 

you have a clutch fuild leak. find it, and replace the part its leaking from. then bleed it.

 

how would it be a clutch fluid leak? Im not trying to say you are wrong.
I am just trying to figure out how thtat would cause my car to fall on its face like that

 

so it feels like its starting out in third gear??
The instant you let the clutch out, the car bogs down? Does it die when you give it gas while in 1st gear? like getting into 1st gear normally.

Try reving to 2k and slip the clutch out in 1st gear like normal, does it feel the same?

 

Kinda except if i started out in third gear i could probably rev it up and still get it to go. I try giving it gas and it just doesnt want to stay on.

and it isnt the instant i let my clutch out. its while im disengaging it so the clutch is still kinda engaged.

I cant really drive it, if i try to put it in first and drive off it bogs and shuts off almost immediately. it even happens in reverse.

I can rev the **** out of it in neutral though sometimes, other times it will start and then just bog and shut off.

 

Most likely disconnected vac hose to the boost sensor....

 

already checked that.

but just to make sure i just went out htere and checked it again, and its good.

that line has a T to the bov and to the engine block and its good.

 

Any ideas if it electrical? or mechanical?
bad ground? relay? anything?

i have been searching and cant find similar symptoms like this

 

turbo car?
S4 or S5

 

TPS calibration may be never seeing closed idle position
and thus will never give acell pump timing to the injectors when moving from idle to off idle
( and thus makes the car want to stall, or force you to clutch ride )

generally TPS error will make the engine hunt at idle ( stock ECU )
but with aftermarket ECU's it may only make the start harder ,, and idle quality lesser,, and make for the clutch riding when taking off

 

^^ I was thinking tps also.
Can be fuel related also, like not enough flow. or a huge airleak lol, but that would make a crappy idle

 

Car is s4 turbo.

so should i check my tps then?

I was thinking if it was a vacuum leak then it wouldnt idle and free rev, also if it was fuel it wouldnt do that either.

 

I always keep it simple when diagnosing problems, the KISS method, Keep it simple stupid. LOL helped me many times.

This might be a stretch but check to see if your leading coil is putting out spark. If the engine is only running on the trailing, it will sometimes idle fine, and free rev just like normal, but when you start to put a load onthe engine, it will bog down.

 

alright thanks man. ill try that 2mrw. any other suggestions so i can do it all at one time?

 

compression test?

What do the plugs look like?

Last tune up? (plugs, wires, air filter, fuel filter)

 

motor only has like 7k miles on it.

it runs and idles now, but it bogs while driving it and it still shitty.

 

so changed the spark plugs, wires, fuel filter and i put a new sock on the fuel pump.

the car will crank fine and idle, it will run for a little while, for like 5 min then shut off and not want to start again for about 10-15 min. then i will turn the key and it will start back up.

any ideas?

 

i put a fuel pressure gauge after the fuel filter and it is reading 20-25 psi during idle. is that right?

 

Sounds sort of like your engine might be starting to get broken in. Sounds like you need to adjust your timing, idle, then tps (test light method worked best for me, but you should also check the range with a multimeter).

Have you checked:

Timing
TPS
Thermowax (coming off of the cam or not)
Idle set screw
BAC
Throttle cable tension

What is it idling at before it drops off and dies now? Does it fall flat or does it seem to struggle to idle (say around 500 rpm) and then choke out?

Something else it could possibly be would be your neutral switch in the transmission. You can check it at the plug with a multimeter, the FSM tells you how, it should only have continuity when in 5th and neutral (best I remember, consult the FSM). Could possibly explain why it bogs in gear, ecu thinks it's still in neutral.

 

It's most likely your water thermo sensor. It sits behind the waterpump under the alternator. I had the same symptoms, changed mine and the symptoms went away.

You might get lucky and it might just be unplugged, if not, replace it, you'll notice better driveability too.

 

appreciate it guys. ill check all those things out 2mrw.

 

fuel pressure should be from 30 to 40 psi

 

the car runs like **** now.

i cleaned **** out the lines and then added a ground from my batt to my starter and now it runs good as hell.