Hesitation under power

[tassie_euro_mk1]

tvr i dont know what my next move is yet...

I might check the fuel pressure and the throttle body. although it does seem to be more of a "sharper" jerking. which i think would be an electrical problem rather than fuel.

but unsure

Ive had a few good drives where it has run just beautifully.

[mollins]

sorry i dont know if the vr6 has an AFM or not, but Ive had this problem in other cars and has been fixed by a good clean out of the AFM cos sometimes it sticks giving wrong A/F.. i just used carby/throttlebody cleaner and it fixed it right up.. if there is no AFM.. please delete this post

[Mrk_Mickey]

TVB as you're in Rozelle, you're not far from my mechanic who has just helped one of my VR6 mates with a new coilpack and leads. He also had the same problem to you and I, and although I thought my mate's problem might only be leads+sparks, he took it to my mechanic and found the problem and got it sorted.

Steve Natoli
0414 579 538
9744 8888
Rear 332-334 Parramatta Rd, Burwood

Hope this helps

[tassie_euro_mk1]

sorry i dont know if the vr6 has an AFM or not, but Ive had this problem in other cars and has been fixed by a good clean out of the AFM cos sometimes it sticks giving wrong A/F.. i just used carby/throttlebody cleaner and it fixed it right up.. if there is no AFM.. please delete this post

mollins do you mean Air Flow Meter? if so yea VR6's do have airflow meters. Mine was knacked and was giving a bad A/F reading but i got a new one and has fixed that problem. But a new problem now lol. This problem has similar effects like AFM but in my case, cant be it. Surely...

TVB, have you checked your Air Flow Meter???

[mollins]

mollins do you mean Air Flow Meter?

yep

sorry .. too used to acronyms.. i guess thats what happens when you work for the government (especially the CSIRO)

good luck finding the problem guys

[TVB]

Sorry guys, I've been away and haven't had much chance to sort anything out with the VR6.
I haven't checked the AFM but I'll give it a good clean. I took the car for a spin yesterday and had a great drive. The VR was flying and there was no power loss at all... so no idea what's going on, but it's probably best to leave her parked until double demerits is over .
I think I'll take it to the mechanic Mrk_Mickey was talking about. Steve, do you have his details please?

[TVB]

Hi Everyone,

Sorry to drag this thread up again but I never had the opportunity to close this properly...mainly because I'm a lazy bumhulio.

Anyway, brief story is;

-I was getting flat spots under hard acceleration, not all the time (see very first post)
-Then engine started running worse. When my petrol tank was below quarter full, the engine would drop revs and the revs would "bounce" between 600 and 1000 RPM a couple of times before it levelled off. This happened when pulling up to lights with foot off the accelerator.
-Then things got worse again and upon initial pick up (i.e. pulling away from lights) the engine would "choke" and I would cough, splutter, and jump my way across a junction before it all fired up and things went normal again.
-Then no start. My engined fired up but died instantly... this was usually followed by expletives!

Turns out it was the fuel pump relay (Item # 191 906 383 C, description - Fuel Pump Relay 2E). Basically as it was dying over the last few months, it would cut out and drop fuel pressure, hence flat spots and bouncing revs with a low tank. Then it died and there was no pressure at all hence no start. The initial start was because of mechanical fuel pump, and then when relay kicked in, engine died.

You can find out if the relay is the problem on cold start. Start your engine, run for a little but not long (maybe 30 seconds, maybe even less, before things get hot anyway) Then pop the bonnet and touch the fuel pump relay. If it's hot, it's dying.

So, I hope this helps and I hope it will save someone the $500 it cost me to find out. Relay is $70.

[h100vw]

Hi Everyone,

Sorry to drag this thread up again but I never had the opportunity to close this properly...mainly because I'm a lazy bumhulio.

Anyway, brief story is;

-I was getting flat spots under hard acceleration, not all the time (see very first post)
-Then engine started running worse. When my petrol tank was below quarter full, the engine would drop revs and the revs would "bounce" between 600 and 1000 RPM a couple of times before it levelled off. This happened when pulling up to lights with foot off the accelerator.
-Then things got worse again and upon initial pick up (i.e. pulling away from lights) the engine would "choke" and I would cough, splutter, and jump my way across a junction before it all fired up and things went normal again.
-Then no start. My engined fired up but died instantly... this was usually followed by expletives!

Turns out it was the fuel pump relay (Item # 191 906 383 C, description - Fuel Pump Relay 2E). Basically as it was dying over the last few months, it would cut out and drop fuel pressure, hence flat spots and bouncing revs with a low tank. Then it died and there was no pressure at all hence no start. The initial start was because of mechanical fuel pump, and then when relay kicked in, engine died.

You can find out if the relay is the problem on cold start. Start your engine, run for a little but not long (maybe 30 seconds, maybe even less, before things get hot anyway) Then pop the bonnet and touch the fuel pump relay. If it's hot, it's dying.

So, I hope this helps and I hope it will save someone the $500 it cost me to find out. Relay is $70.

The fuel pump relay is in the fuse box not under the bonnet..... Are you maybe talking about something else???

If the motor kicked for a few seconds, that would be because the relay primes the fuel system briefly when you turn the key. The motor would run and use up the fuel in the lines and then cut out. Fuel pump relays have a habit of manifesting dry soldered joints in them. They start being intermittent like yours has been then they quit completely.

At the first sign of trouble, I take the covers off them and re make all the soldered joints. They usually last for ever after doing that.

The other thing I recently discovered with old VWs is the carp quality of the fuses, I had one that looked OK and fed the rad fans, caused a boil over which split a hose...... I'd pull out and replace any VW fuses with a new set.

Gavin

Gavin

[The_Hawk]

post up some pics of teh parts your talking about TVB, then we can all be sure we are talking about the same bits.

[TVB]

Cheers Gavin,
No, I'm talking about the relay. I just took my car to a dealer in the end, hence the cost and my lack of knowledge of where the relay was. I had a VW mechanic come round and have a look and he told me the immobilisor had gone and needed new keys from Germany and car re-chipped to keys etc, etc so I was at a loss. I'm glad it's all solved now though and everythings running well... for now.
I may do a fuse replacement as you've suggested.