Idling high, plus other problems ; replaced ISC

[merqury]

Car - 95 Talon TSI AWD. I have a lot of problems which I think may be interconnected.

Firstly the car idles really high, when I start it, it usually idles around 1500. Then after driving around a bit it idles around 2000-2500. I already replaced the ISC with a new one and cleaned the throttle body, but the problem is still there.

Also, a lot of the dash lights always stay on, the e-brake, coolant and battery light. I just put in a new battery and checked coolant. The lights sometimes dim and then come back on. I am guessing this is the alternator? Could this be related to the idling problem?

Also, there is a slight bogging/hesitating problem. I already changed the plugs and wires. I am thinking there is a vac leak somewhere. I just made a boost leak tester yesterday. Will a boost leak test tell me about vac leaks? My boost gauge (autometer) shows only 10 vac at idle; if I am right it should be 20. Sometimes in first gear the gauge always stays at vacuum.Can this be related to high idle as well?

Car's stock; the previous owner put in a new bigger IC pipe with BOV. Could this require a BISS re-adjustment?

Thanks for your help.

 

[SloWPanda]

Did you have anything to do with lose of coolant or changing the thermostat? Because having air bubble in the coolant can cause the car to idle.
Another thing i came across with my car after replacing the IAC, was my MAF sensor was bad. Thats solved my problem.
Ebrake probably just need an adjustment, is it loose and wobble around freely?

 

[merqury]

As far as I know, the thermostat wasnt changed and there's no loss of coolant.

Its not just the e-brake; all the dash lights are coming on.


UPDATE 10pm: Just saw the coolant leaking out the cap - what to do???

 

[doggo]

...

UPDATE 10pm: Just saw the coolant leaking out the cap - what to do???

Try installing a new cap.

 

[RedTurboEclipse]

the 3 lights usually means alternator

check your throttle cable to make sure its not sticking

and yes 10vac at idle is low, unless you have cams, but you do not. this can indicate a leak somewhere, which is usually the case, worse case is something wrong with the motor, but i highly doubt it.

 

[merqury]

Thanks for all your replies. The car is now vacuuming at around 6-8 now, even worse. Does this have something to do with a vac line or a boost leak?

Also, the turbo doesnt boost past 0 on my gauge. Sometimes it may go up to around 5, but thats it.

 

[tqmx1]

Man, The only thing that can cause that much of a vacuum leak is the brake booster or the line between the intake and the booster.

If the line is on remove it and cap it off and try it again.

 

[merqury]

the line between the intake and the booster.

Are you talking about one of the lines coming out of the Air Intake pipe/tube?

 

[tqmx1]

Yes the 3/8" line on the left side of the intake. There is not much else that can cause that much of a vacuum leak.

 

[Charlie90GST]

I have a 1G, just replaced the water pump, now it idles at 1500 constant, I saw someone say that bubbles in the coolant lins could cause this? If so, how can i fix this? sorry to hijack this but its driving me nuts. Now as to Merqury's problem, Did you reset the BISS screw after replacing the iac and removing the throttlebody? you might also want to cheack the Fiav for leaks as well.

 

[merqury]

Well the idling problem is better now - it idles from around 700-900. It fluctuates a lot and I'm thinking that this is due to the alternator. Its still not boosting past 0 on the gauge even at WOT. I'm planning to do a boost leak sometime this week and see what happens.

 

[tqmx1]

7 to 900 sounds about right. sounds like a brake booster is next in line to be changed. As for the alternator get a volt meter and see if it is putting out. 12.5 or less you are on the battery 13.5/ 14.5 you are charging. As for the surging it sounds like a bit of tuning is next in line.

 

[merqury]

Do you think the ECU has anything to do with all this?

 

[tqmx1]

No, Check the voltage set the BISS and let the ECU relearn the engine. Get it up to opperating temp shut it down disconnect the battery let it set for about 10min. reconnect the batt. fire it up and let it idle for about 10min. to relearn the idle settings.

 

[merqury]

Well I changed the battery, so I guess the ECU is re-learning the engine. I have another question now; I found a HUGE exhaust leak; I think its the turbine inlet gasket (manifold - turbo). Could that be the reason for low vacuum and idling issues?

 

[tqmx1]

No but it would account for a lack of boost. Make sure the four bolts are tight and if so plan on changing the gasket.

 

[tqmx1]

Just a quick one, Make sure the vacuum lines on the throttle body are on the correct location. If they are out of order it will give all sorts of fits.

 

[merqury]

Turns out the gasket blew, along with my turbo.

Regarding the vac lines, what does the P, E, A stand for? Also, does the BOV have any part to play in the idle problems?

 

[tqmx1]

Do you have a maintance manual for the car? If not any parts store eather will have or can order you one, that will give you a heads up on the plumbing. As for the blow off valve if the diaphram is leaking yes it could, do like you did with the brake booster and try it. As for the pop off portion, NO

 

[merqury]

Back after a long time. Got a new turbo put in, and I changed the alternator. Now the lights on the dash are gone. Car boosts fine.

The idle problem's still there. Checked all vac hoses; sprayed brake cleaner on them but no results. It idles at around 800 now, but its VERY rough - the whole car shakes. When I turn on AC/Defog, it drops down lower and seems like its going to turn off. Sometimes it gets stuck at 2000 and stays constant. Does this have anything to do with the throttle cable?

Also, should I put the stock uic pipe w/ stock bov back on?

 

[AWDGreenMachine]

Did you ever fix the problem? If not... I have one question for you, are you venting your bov to the atmosphere or is it reciculated back to the intake? If you ARE venting, that could be your idle problem.

Good luck!

 

[gringo72884]

i would strongly recommend a leak down test and compression test. I had something similar happen to me and I found out I had skipped a couple teeth on my timing belt.