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PhatVR6

VR6 down on power, getting p1ssed off with it now......

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VR6 running a bit lumpy, and well down on the power. ran a pathetic 14.9 on sunday, the rest of the times were either a flat 15 or 15.3.

 

The car hasn't got enough power to smoke the slicks, I reckon 170bhp tops, if that. so that ruined my racing on sunday, and meant I couldn't race on monday either as there was no point with it running like that.

 

it takes loads of cranking to start it up, sometimes it stalls immediately, or revs up and down. it hesitates at low revs (i.e. not very good throttle response), massive flat spot at 4000rpm, then pretty much flat about that. no massive kick at 4500rpm like it was doing last month. My mates rover 220 turbo was all over it, he was practically pushing me along the road.

 

I know it can't be anything major, becasue when it is running right it goes like f*ck, and is certainly quicker than my mates mk2 turbo, and that runs a 14.4.

 

I know the power has been there, but where it's gone now I just don't know.

 

I just never realised it was running flat as it's been running on practically 5 cylinders for the past fortnight due to an arcing out plug lead, so when I fixed that I thought it was running fine. and my mate who I took out in it also thought it felt REALLY quick. considering it had 2 people in it, a full size 16" spare, a tool box, and a trolley jack in it, and it weas still quicker than his car and that runs mid 14's. but for some reason it just wouldn't perform at all on the day, and the more I drive it the more I can feel the flat spots.

 

my mate said it puffs out black smoke when I change up a gear. to me, that's unburnt fuel, either from an excess of fuel, or becasue it's not burning due to a poor spark or whatever. sounds logical?

 

:cry: :cry: :( :mad:

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Is there anything left to be changed at all?

 

Would a rechip and RR session maybe iron out some of the flat-spots?

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I'm going to borrow the AMD ecu off my mate again. I did notice that the 4000rpm flat spot came in after I'ld swapped back tot he stock one. but I'm sure it still went pretty well up top. certainly better than it does now.

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shcrick isn't on.

 

I daren't put it on until I can get it firing on 6 properly. I've lost count of the amount of times I've had the plugs out....

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Yeah I know that feeling!

 

Not too sure to be honest as you will have undoubtedley treble checked everything I would have......

 

Are you running the same map you had with the engine shricked and cammed? I take it the engine is just cammed at the moment?

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Phat im no big expert on vr's but sometimes guys have lack of power etc and its due to sensors

 

I.e lambda, hall sensor (think it picks up on the cam position and there is two of them)?? coil pack if urs is, and MAS sensor.

 

Just a idea but im guessing u know all this already

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OT but when you're on the track and carrying a trolley jack(!!) and full-size spare, how do you stop it bouncing around the boot and putting holes in the bodywork?!

Also, back on-topic, I wonder if you've checked all the injectors again - I know you had trouble with one of 'em a while back, maybe the others were marginal too?

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OT but when you're on the track and carrying a trolley jack(!!) and full-size spare, how do you stop it bouncing around the boot and putting holes in the bodywork?!

Also, back on-topic, I wonder if you've checked all the injectors again - I know you had trouble with one of 'em a while back, maybe the others were marginal too?

 

you don't, you take it all out and leave it on the grass.

 

I''m thinking it's not injectors, as the plugs look fine, the mpg isn't too bad either, and it's producing black smoke.

 

Just ordered some Autotech 10.4mm ones :lol:

 

already tried another fuel pump, as that's what I thought it was.

 

going to try another FPR.

 

need to fix that blowing exhaust too.

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OT but when you're on the track and carrying a trolley jack(!!) and full-size spare, how do you stop it bouncing around the boot and putting holes in the bodywork?!

 

you don't, you take it all out and leave it on the grass.

 

That's what I thought.. What about the trip to/from the track then! I can't help but go round corners from time to time.. :|

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change the blue coolant temp sensor... for the sake of £7 it's not worth overlooking... ;)

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don't discount it just 'cos it's new... ;) Had one that I took back 'cos it was DOA... :roll:

 

It's worth checking it with a multi meter just to rule it out once and for all... :)

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it's been running perfect. I cna't see it going down after a months use, not when I've been running VR's for 5 years and this the only time i've ever changed one.

 

The sensors I am suspect about, is the outside air temp, as it seems to read a little high, 32 degrees the other day. then again, I do have it mounted inside the air filter!

 

Also, because I'm running a 1991 passat inlet manifold, there is no where to plug in the inlet manifold temp sensor, so I juat have that sitting in the open air.

 

so I think it could be confusing the ECU if it thinks the air insode the manifold is colder than that outside?

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I'm pretty certain that the outside temp sensor is ONLY used for the MFA display, so there's no way that this should be able to upset the MFA...

 

Dunno about the inlet manifold temp sensor... that's where you hit VR things that I've no experience of... :?

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If the ECU is being told it's inlet temp is way wrong compared to the real inlet temp it will feck up the fuelling - it uses a combination of the MAF and the inlet temp to work out how much air went in (the MAF tells it air flow rate, not air mass rate contrary to it's name). Does the bad running coincide with hot days, or sitting in traffic, or something like that?

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Where is the sensor supposed to be mounted, on a Corrado inlet manifold? Cos the manifold gets quite hot. If it's reading 30 degrees instead of 100 degrees, that'll mean it'll be overfuelling by quite a lot I'd guess.

If anything, if you sit in traffic for 30 minutes and heat soak the under-bonnet area you'll probably find it gets less bad, cos the difference is smaller.

That's IF I'm not talking through my arse..

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