Cutting Out When Warm Only ?

[frosty_vr6 2]

Need some help on this one guys been trying to resolve this issue for months ,

 

When restarting the car when the engine is warmed up only it either cuts out straight away after you have turned the key or will cut out at one of the first few junctions at random when coming to a stop and dipping the clutch its like its not catching the idle, as soon as it cuts out it starts back up instantly on the key no longer cranking time or waiting to cool down, when restarted its back to normal drives fine and holds idle correctly at junctions etc, occasionally it will do it more than once on a drive but most of the time it does it once and its fine anyone have any suggestions ??

 

So far i have cleaned the MAF, Intake boot(checked for cracks also) and part of the TB you can see with the intake boot removed.

 

Have also changed: Blue temp sensor, Crank sensor just changed the 02 on the CAT and new CAT also, I bought a new scanner (Foxwell NT-510) and scanned it before doing the 02 sensor and got only 1 code:

 

00525 Oxygen Sensor G39 - Sporadic-Implausible Signal

 

No engine speed code the one everyone gets when the engine is not started which i thought was strange but the crank sensor is new and if faulty would surely throw a code anyway so cant really see why that code is not showing.

 

Now the 00525 code has gone and the car is showing a system pass no faults found on the engine scan so that must of been a problem but not THE problem as the car is still doing it.

Car is a 1996 OBD2 and manual 

 

Bit stumped by this one guys any help much appreciated,

 

Frosty

[Bealieboy 1,625]

Need some help on this one guys been trying to resolve this issue for months ,
 
When restarting the car when the engine is warmed up only it either cuts out straight away after you have turned the key or will cut out at one of the first few junctions at random when coming to a stop and dipping the clutch its like its not catching the idle, as soon as it cuts out it starts back up instantly on the key no longer cranking time or waiting to cool down, when restarted its back to normal drives fine and holds idle correctly at junctions etc, occasionally it will do it more than once on a drive but most of the time it does it once and its fine anyone have any suggestions ??
 
So far i have cleaned the MAF, Intake boot(checked for cracks also) and part of the TB you can see with the intake boot removed.
 
Have also changed: Blue temp sensor, Crank sensor just changed the 02 on the CAT and new CAT also, I bought a new scanner (Foxwell NT-510) and scanned it before doing the 02 sensor and got only 1 code:
 
00525 Oxygen Sensor G39 - Sporadic-Implausible Signal
 
No engine speed code the one everyone gets when the engine is not started which i thought was strange but the crank sensor is new and if faulty would surely throw a code anyway so cant really see why that code is not showing.
 
Now the 00525 code has gone and the car is showing a system pass no faults found on the engine scan so that must of been a problem but not THE problem as the car is still doing it.
Car is a 1996 OBD2 and manual 
 
Bit stumped by this one guys any help much appreciated,
 
Frosty

Crankshaft sensor

[frosty_vr6 2]

4 minutes ago, Bealieboy said:

Crankshaft sensor

Thanks for the reply Bealieboy , i replaced that first as i was pretty much certain that was the cause bought a genuine new Bosch one as well , i suppose it could be duff if that is possible ? think i have a spare here i could try.

 

  

[Bealieboy 1,625]

Thanks for the reply Bealieboy , i replaced that first as i was pretty much certain that was the cause bought a genuine new Bosch one as well , i suppose it could be duff if that is possible ? think i have a spare here i could try.
 
  

Hmm. Normally when no engine speed recorded on diagnostic tool, that's gonna be due to the crank sensor, that's directly where engine speed signal is measured.
It's 100% gonna be a Sensor. If you got a spare, try camshaft sensor too, it surely has to be one of those two

[markhaywardbailey 3]

Hi frosty I had exactly the same problem and couldn't work out what was going on . Mk3 vr6 1996 obd2 aaa . Drove to the shops engine up to warm . Got the shopping and when I restarted the engine it would rev then just die. It would restart and then be fine !! I checked and replaced the crank sensor and maf still same problem . Thought I'd take the throttle body off and clean it . I removed the air intake pipe to the throttle body and noticed a very small spilt on the underside in between the concertina . The underside gets hot from the exhaust manifold and the heat was causing the split to open up and causing the engine to die. I sourced a secondhand part off eBay and presto the problem was gone (I temp wrapped in tape til it arrived).
Hope this fix is the same in your case, let me know
Cheers
Mark

[frosty_vr6 2]

22 hours ago, Bealieboy said:

Hmm. Normally when no engine speed recorded on diagnostic tool, that's gonna be due to the crank sensor, that's directly where engine speed signal is measured.
It's 100% gonna be a Sensor. If you got a spare, try camshaft sensor too, it surely has to be one of those two

Yea its strange i do not think this scan tool is showing all of the codes for some reason as no way on earth did the car only have one code it could have but i very much doubt it lol

but it did show my ABS codes that i knew should of been present so i suppose it could be.

 

But that with the fact that no engine speed code is showing when the engine is off tells me something is not quite right and you are spot on with what you say it makes sense hopefully replacing one of them will resolve it, i tried just plugging in my spare new crank sensor earlier without removing the new/other one scanned it and still did not show the engine speed code which is just weird i am going to try replacing it tomorrow anyway as i am aware it possibly may need to be actually installed (as it is basically a magnet) for it to work

was peeing it down today so did not get chance to get under the car to swap it over ,

 

I then tried replacing the Camshaft sensor with one from my other golf too see if that would help with throwing the engine speed code but it did not so i am really not sure now i am going to try firing it up when warm a few times tomorrow with the Camshaft sensor now replaced see if its that if not then try the new Crank sensor if not that then have a really good look at the intake boot as Mark mentioned and check again for any cracks or splits.

 

Thanks for the advice much appreciated i will keep this thread updated

   

[frosty_vr6 2]

46 minutes ago, markhaywardbailey said:

Hi frosty I had exactly the same problem and couldn't work out what was going on . Mk3 vr6 1996 obd2 aaa . Drove to the shops engine up to warm . Got the shopping and when I restarted the engine it would rev then just die. It would restart and then be fine !! I checked and replaced the crank sensor and maf still same problem . Thought I'd take the throttle body off and clean it . I removed the air intake pipe to the throttle body and noticed a very small spilt on the underside in between the concertina . The underside gets hot from the exhaust manifold and the heat was causing the split to open up and causing the engine to die. I sourced a secondhand part off eBay and presto the problem was gone (I temp wrapped in tape til it arrived).
Hope this fix is the same in your case, let me know
Cheers
Mark

Thanks Mark for the reply that is very interesting i will take another look at the intake boot tomorrow for sure as this does seem to be one of the few things that would supposedly not throw a fault code. By concertina do you mean the griddle'd flexible piece close to the MAF side a few inches long or one of the ridges/bulges right on each end of the intake ? 

Thanks again for the suggestion much appreciated Mark

[markhaywardbailey 3]

Yes exactly that it was difficult to detect and only occurred when engine was hot. I went through the same pain using diagnostic tools and no codes were shown, the forums told me to change the maf and crank sensors which I did but made no difference
(And changing the crank sensor is fiddly with little access)
If you splay the intake pipe check for cracks/ splits or as I did block the end with my hand and put the other over my mouth and give it a good blow see if it leaks
Hope this helps
Mark

[Bealieboy 1,625]

Engine speed sensor only showed fault on mine when scanning live data.
It definitely didn't show a code

[frosty_vr6 2]

23 hours ago, markhaywardbailey said:

Yes exactly that it was difficult to detect and only occurred when engine was hot. I went through the same pain using diagnostic tools and no codes were shown, the forums told me to change the maf and crank sensors which I did but made no difference
(And changing the crank sensor is fiddly with little access)
If you splay the intake pipe check for cracks/ splits or as I did block the end with my hand and put the other over my mouth and give it a good blow see if it leaks
Hope this helps
Mark

Sounds pretty much identical to my issue, I removed the Intake boot today and have found a tiny and i mean tiny split on the part where the PCV connects to it, enough to let air through i just cant really tell if there is any more holes as its pretty hard to get a decent seal on it, i ended up sealing both large ends using a strong thick bag with the metal screw clamps then blowing through the PCV inlet i noticed something tickling my chin lol and it was air... had a close look and sure enough i have found one hole so far and i reckon there is more possibly, the bag seals i made stated to leak then so i am going to try again using electrical tape instead of the clamps to hold the bag on and will report back tomorrow, ideally i want to try and get it submerged in warm water with the ends sealed and check for any bubbles, had a right laugh earlier trying to seal and blow into it, think i will just bite the bullet and get the 42 draft designs metal intake and the PCV fix kit to try and completely eliminate any issues with a possible air leak but will see if there is any more holes first, i would not of found it if you had not said so thanks for the input much appreciated Mark

[frosty_vr6 2]

47 minutes ago, Bealieboy said:

Engine speed sensor only showed fault on mine when scanning live data.
It definitely didn't show a code

Yea live data will be next port of call, i think when i checked it a few days ago i saw the RPM on the live data and it was moving when i gave it throttle but i am not to sure if it was the engine speed or RPM it said , Is your car OBD2 ? as far as i was aware all VR6's show the Engine speed sensor code 00513 Static-No signal if the engine is not running because if its not running then it is not showing a signal i thought this is normally whats supposed to happen and they all did this so i was concerned and surprised when i did not see this code appear i checked my other VR which is OBD1 and that is the only code that shows up on a scan so it got me thinking something is not quite right. but maybe its just OBD1 that shows a code for this.

Thanks again for the input Bealieboy  

[Bealieboy 1,625]

Mine is obd2 fella. Dd42 pcv delete is great btw. I bought mine direct from USA rather than from uk. It was much quicker to arrive rather than the one my mate ordered from a uk store. Because guess what, the store waits for a substantial order before placing an order with dd42 in the USA..

[frosty_vr6 2]

Yea that is typical will be ordering it from the states been looking on the site today, only place i could find it over here was Awesome GTI and they want £140 for the intake pipe and they do not sell the PCV kit that i could see ,the intake kit is around £100 directly from 42 so its a no brainier will probably work out around the same with shipping and import charges but i want the PCV kit with it, What did you do with the little tube coming off the top of the PCV disc btw if you do not mind me asking as i was wondering earlier what to do with it should i just put some silicone sealant in it ? . So yours is OBD2 and you do not get a Engine Speed code either when scanning with the car not running.

 

Thanks,

Frosty

[frosty_vr6 2]

Update, tried changing MAF & Coilpack but the problem remains,

i have new leads and plugs here to go in next, still not getting any codes at all but i am getting 098-4-ADP MODE-ERROR on live data which i believe is the throttle body adaptation could mean: throttle body is dirty, stretched throttle cable, wiring fault, faulty TB or ECM fault apparently.

 

Next on the list to try:

1. Plugs and leads

2. Throttle cable & Remove TB for a thorough clean

3. DD Intake Pipe

4. Spare new Crank Sensor 

5. Blue Coolant temp sensor as the one i fitted was a cheep one

6. Fuel filter have a new one here

7. FPR as i have a new spare here somewhere 

8. Immobilizer chip reader as i have a spare here

 

Just to recap i have so far changed: Crank Sensor, Cam Sensor, Blue Coolant Temp Sensor, 02 Sensor, CAT, Coilpack and MAF

 

Checked Intake pipe for possible cracks found one small split sealed that and sealed around the PCV,

Cleaned Intake pipe, PCV and connecting pipes thoroughly

Cleaned inside the TB where the intake attaches

Inspected and cleaned positive on alternator, earth on the block, and battery terminals also fitted a new battery, Ignition switch and starter motor are new aswell

 

If anyone has any other thoughts or suggestions it would be much appreciated.

 

Thanks,

Frosty