Cars doing my head in

[bilko0795]

As per title the old girl is doing my head in at the mo what with battery drain/ boost leaks and other niggly bits.

I did a boost leak test again on Sunday and found that the hose from I/C to throttle body had came off the I/C side so put it back on checked all the clips did a test found a small leak from the back of the boost gauge i have just fitted fixed that tested again no leaks opened her up on Monday everything fine coming home tonight over taking a car and started kangarooing up the road not even full throttle, how embarassing when im on the outside overtaking and the guy looking at me stupid. I can't figure out why one day fine and the next not. Drives ok when normal driving.

My son is going to Vagcom the car on Saturday what i need to know is what to look for when doing a live log on the maff and also for the boost what sort of figures do i need to look out for. we are both new to vagcom so are still learning. Any input from the tech guys on here would be most welcome.

[Drummer87]

I had this kangaroo before. Was failing coil. Then my n75 was knackered. And my isv was slack. Mines driving smooth but not hitting peak boost. Sometimes it does most times doesn't. Fuel v power. Checked gaps on spark. Renewed sparks.

Just the joys of chasing leaks in the tight spaces.

Is the leak testing holding pressure?? Can you gauge it. Also spray soapy water around for bubbles

[UrS4boy]

You've probably had an ignition problem developing for sometime and finally getting the boost leak fix had made it show up. However, it could be a wastegate spring that is too strong/tight/wound in.

Missing and hesitation diagnostics:

http://forums.quattroworld.com/s4s6/msgs/22611.phtml

Power Output Stage (and coil) diagnostics:

http://forums.quattroworld.com/s4s6/msgs/153152.phtml

[bilko0795]

[QUOTE=Drummer87;731843]

I had this kangaroo before. Was failing coil. Then my n75 was knackered. And my isv was slack. Mines driving smooth but not hitting peak boost. Sometimes it does most times doesn't. Fuel v power. Checked gaps on spark. Renewed sparks.

Just the joys of chasing leaks in the tight spaces.

Is the leak testing holding pressure?? Can you gauge it. Also spray soapy water around for bubbles[/QUOTE

No can't gauge it have sprayed with soapy water that's how i found the last leak will do a leak test again this morning. for piece of mind. just thinking if there is still a leak at the gauge will it still cause the car to behave the way it did ?

[bilko0795]

You've probably had an ignition problem developing for sometime and finally getting the boost leak fix had made it show up. However, it could be a wastegate spring that is too strong/tight/wound in.

Missing and hesitation diagnostics:

http://forums.quattroworld.com/s4s6/msgs/22611.phtml

Power Output Stage (and coil) diagnostics:
http://forums.quattroworld.com/s4s6/msgs/153152.phtml

Thanks for the link Dave will start checking this today.

[Thuppu]

If you have orginal coils, I recommend to do the tfsi coil conversion.

[bilko0795]

If you have orginal coils, I recommend to do the tfsi coil conversion.

Only just bought Oem ones 6 months ago £480. I should of done the conversion .

[Thuppu]

Well, then I doupt the coils would be the problem. They are known to work fine for 20 years or so. What spark plugs do you use?

[bilko0795]

Well, then I doupt the coils would be the problem. They are known to work fine for 20 years or so. What spark plugs do you use?

Bosch F5DPOR im thinking of changing to NJK Irodium or platinham.

[prj]

If you do not block the throttle body and pressurize just from the MAF hose with the breather plugged on the maf-turbo hose end, how long does it take for the pressure to drain from 0.5 bar to 0, after you cut off the supply?

It should take at least 20-30 seconds.

[bilko0795]

Well don't what's going on here went to work this morning thought i would try the car give it some welly car pulled really well boosted to 1 bar then settled on 0.8 did it a couple of times no trouble with kangarooing however on the way home i thought i would try again and this time would only boost to 0.4 /0.5 no hesitation. Somebody on here must have had this problem before and can enlighten me to what they know or suspect what it might be.

[bilko0795]

If you do not block the throttle body and pressurize just from the MAF hose with the breather plugged on the maf-turbo hose end, how long does it take for the pressure to drain from 0.5 bar to 0, after you cut off the supply?

It should take at least 20-30 seconds.

I take it you mean the boost gauge, if so i will be doing a leak test again on the w/end so i will look at this as i suspect it may be still leaking.

[prj]

How do you pressure test the car?
Usually one uses a tyre inflator so you can see how much pressure is currently in it.
Boost gauge has nothing to do with it.

[bilko0795]

How do you pressure test the car?
Usually one uses a tyre inflator so you can see how much pressure is currently in it.
Boost gauge has nothing to do with it.

Got confused there for a mo because i had mentioned that i had a leak at the boost gauge and you said bar i somehow thought boost gauge yes i use a tyre inflator.

[prj]

Yea so put half a bar in (7-8 psi) and then watch the tyre inflator gauge, and see how long it takes to drop back to zero.

If it's instant you still got a leak.