VR6 aaa wont start HELP!!!

[courtz1976-2dr]

HI there all,

once again I seek the knowledge of the vw fans.

Here is my issue that has started in the last month

most predominant when cold the car wont start

crank crank crank little fire no start crank and crank and it will sluggishly fire after many attempts (strong fuel smell)

once started runs ok little occasional surge of idle.

Usually then starts fin when hot

Sometime when left alone (when hot) it exhibits the same non-start issue.

because of fuel buildup a couple starts ago it blasted the "damper" on isv to bits, it has been bypassed and problem still persists

only other issue is slight misfire when changing from 2nd to 3rd

have soaked the ignition module in water whilst running and see no arcing and no misfires

have unplugged maf and car seems to accelerate harder but slight hesitation on dumping full throttle runs well otherwise

unplugged tps (maf plugged in) same deal car seems to run ok does not seem to accelerate as hard

unplugged both car starts (when running hot) but surges up down up down runs like crap (expected)
plug in maf idle stabilises, remove maf, plug in tps idle stabilises

when in "not starting mode" rev register on tacho when cranking (about 200rpm maybe a little less)

good power at ign mod connector.

spark on crank (when not starting) it doesnt seem as fat maybe

what can be causing this intermittent problem what else in the ignition/fuel system would affect the abilitly to fire.

GRRRRR please help!!!

???ANYONE with any suggestions most recent test was ignition switch bypass (ign on jumper from solenoid to battery) and still wont start.

I think the isv isnt working as it should but i tried removing it and plugging both holes and trying to start and STILL NO GO COILPACK??? do they do this intermittently when they are about to fail?? thing is though when running is fine. What relays should I be looking at next???

[courtz1976-2dr]

HI there all,


???ANYONE with any suggestions most recent test was ignition switch bypass (ign on jumper from solenoid to battery) and still wont start.

I think the isv isnt working as it should but i tried removing it and plugging both holes and trying to start and STILL NO GO COILPACK??? do they do this intermittently when they are about to fail?? thing is though when running is fine. What relays should I be looking at next???

OK update again. with the isv deleted and holes partially plugged on engine side of throttle body I get nice easy starts, obviously idle is a bit erratic. SO ISV is dead no humming and generally not doing what it is supposed to do. I think this is the diagnoosis
1. ISV got a bit stuck closed - rich start
2. backfire busted the damper to bits
3. bypass of damper
4. ISV decides to die/ dying or busted with backfire
5. No or intermittent start, ie when valve decides to sit in a nice position allowing start.

Anyone know where I can get one orig part no is 0 280 140 512

Cheers and thanks is advance.

[mb1907953]

Hey mate,

There is an OBD 1 VR6 getting wrecked up at Boondall auto wreckers. fairly sure all the gear was there when I was up there. Otherwise try imparts or tooleys imports.

[Jmac]

Be quick I got a lot of stuff from it anyway I would be having it scanned and see what the coolant temp sensor is saying, had one AAA read minus 50degrees, was flooding itself something cronic, happened to be a very special VR6 on here. Try the temp sensor mate, blue in colour, even if it doesn't happen to be it as this is an internet diagnosis at least its done for any future issues
Cheers
Jmac

[courtz1976-2dr]

Be quick I got a lot of stuff from it anyway I would be having it scanned and see what the coolant temp sensor is saying, had one AAA read minus 50degrees, was flooding itself something cronic, happened to be a very special VR6 on here. Try the temp sensor mate, blue in colour, even if it doesn't happen to be it as this is an internet diagnosis at least its done for any future issues
Cheers
Jmac

You are a legend
Blue temp sensor was reading 12kohms way outside reference range but now have a weird one

at operating temp car jumps straight to "fan super fast mode"

Anyone know where I can get all three sensors. Just to "rule them out"

Cheers again - I had cehcked all wirng to here but not the sensor itself, it is strange that the ECU would accept a reading SO FAR OUT?!!!

Thanks for your help!!!!! (((this is after getting new isv too!!!! Grrr)

[Bug_racer]

Change the oil pump

[courtz1976-2dr]

Hi bug racer

Seems a little random what's the reasoning ??? Is this just preventative I haven't really had any pressure issues. Light goes out within first revolution of cranking plus no overheating issues. Top end is a littltle tappety but timing chains were done less than 30k ago.

Cheers,
Courtney

[Chris1]

Hi mate,

On the MFA what is your fuel consumption reading after driving for 20 odd mins. (On Position 1) Should not be more than 12-13 Ltrs/1000kms. On my VR6 had similar issue. Oxygen sensor was sticking rich. You can check this Via VAGCOM if you have access to a unit. Else if the car has done more than 100,000kms without a change. I would be replacing this. Mine was also very fuelly prior to changing this.
Forgot to check.. You have obviously checked your air filter isnt blocked I am assuming. And no intake vac leaks? If not I would look at the O2 sensor. I think cost me like $160ish for a denso probe off ebay. Only hassle was postage from the UK took like 2 weeks...
Good luck.