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Pulls better when running cold?


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For those of you that might know the car, it was Mangold's highline before I bought it.

I've noticed a few times that when running cold, it's got a lot more torque that when fully warmed up.

Like most people I have a daily run to/from work, there are a few roundabouts close to work and I've noticed when cold (first few minutes of running), when I'm pulling out, there's a lot more go - so much more it sometimes takes me by surprise. !amazed

Now when it's warmed up, it feels fine, runs smooth and doesn't appear to be missing any power so I'm not sure if it's a normal thing, or maybe it's just running a bit lean when warm.

At first I did think I was imagining it but it's definately true and I'm not trying to put my foot down or anything, I take it very easy when it's not warmed up but on light throttle there's definately more urge...

I've got a cable, I just need to purchase the VAG.COM software to go with it, but without a gas analyser I'm not sure if I can pick anything up anyway.

Any ideas, is this a normal phenomena?

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Baring in mind, Vinces' old car and mine are pretty much identical engine mod wise, I notice mine is exactly the same. I put it down to the lack off heat shield on the Ram Air, so the car will always perform better on a cold day, or when the engine bay is cooler. This is due to the car prefering cooler air, therefore running better and producing more power!

Simon.

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So is heat soak that bad that it noticibly reduces power by what seems a large amount with the ramair kit?

If that's so, surely we're losing power over a standard airbox when the car is warmed up?

Vince gave me the original airbox (actually he gave me a boot full :P ) I might try fitting the standard type to compare - of course, I just packed it away in the loft last weekend. !grr

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Could also be due to the car running rich when in 'choke' mode ;)

Has the car ever been maped for fueling???

My appologies but i don't know the car.

A word of advise also' date=' try not to thrash the car from cold or even load it up excesivly ;)

[/quote']

Apologies not required! I didn't know the car until I bought it. Mangold has kept it impeccably though and at least a few of the members know the car but not me..

The car has been remapped by AMD and I have the readout's of the rolling road session giving a very healthy 208bhp and 209lf/ft or torque. That was about a year ago, no idea if it's putting out those figures now, of the VR6's I drove it feels as fast as any of them but smoother and more torque lower down, but it's a bit hard to judge without having a standard one back-to-back.

Yes, I'm sure it's running richer when on choke, but that should make it produce less power, not more - that's the puzzle!

I've a very good boy too, 3000 rpm and probably a max of half throttle when not up to temp. tbh, I drive pretty sedately most of the time and only put my foot down on open roads.

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not a good idea to boot it from cold, but its probably the engine running on rich (as stated previously), the o2 sensor hasnt warmed up, so the car is dumping a fair amount of fuel in, it make it feel quite torquey to start with even if your not ragging it, just pootling around.

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u boot it when the engines cold?????? !dodge !dodge !dodge !dodge %-6

Eh? I've mentioned several times I DON'T boot it until it's fully warmed up and not even then during normal driving...

I've read through the posts... can't see me even mildy insinuating booting from cold! %-6 ;)

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even if you did m8, its your car to do with as you please ;), on the rare occasion i have gone up to 3000rpm before my water gate has got to the middle, sometimes you can help it, you need to overtake or something, its bad if you do it all the time i guess.

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even if you did m8' date=' its your car to do with as you please ;), on the rare occasion i have gone up to 3000rpm before my water gate has got to the middle, sometimes you can help it, you need to overtake or something, its bad if you do it all the time i guess.

[/quote']

Having raced sprints and built my own engines about 12 years ago, I'm probably the most mechanically sympathetic driver I know. :D Ask any engine builder or even the manufacturers, they'll be some variance, but around 70-75% or revs and throttle is the recommended max when not at full working temperature. Well 70% gives a cold (and I don't mean stone cold) rev limit of 4600 rpm on the VR6, I rarely rev that high when hot. :D 50% from stone cold is a "normal" recommended max but it varies depending on the engine, smaller engines are better off not being run at too low revs or you do more damage by labouring the engine than you would revving it. Obviously the the VR6 in a mk3 golf pretty much isn't labouring ever - it'll pull on light throttle from 1000 rpm without labouring.

Um.. yeah, basically I do understand the concept of not booting it when cold.

Anyway, back to the subject in hand - a cold engine under choke conditions shouldn't produce more power on light throttle than a warm engine running it's correct mixture, choke conditions aren't optimal for power, they're optimal for consistant firing - hence it "feels" like it's running a little leaner than optimal. That could be the way AMD set them up, I've no idea. Maybe the standard cars are like that too? Again, not having owned one before I can't say.

But during my driving career I've probably owned 25+ cars and driven at least 100 different models (motor trade until about 1993) and never really come across that before except on cars that were running too lean, but that was really in the carb days.

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my VR was really responsive with the ram air on when it was cold but once the engine bay had warmed it lost some power but sitting in traffic the power loss was just a joke!!!

i bought some stainless sheet to make a heat shield out of but took the ram air off instead. got some titanium sheet as well, that stuff is awesome!!!!

i think theyre pretty safe to boot as soon as the cold start is cut out. oil temp should be sufficient enough.

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I might swap it for the standard box and filter and try that for a week, it's not like it takes long to do.

I think I'll also get a temp probe for my multimeter and measure the underbonnet temps just to see how they rise.

I used to have a Mini ERA turbo, that suffered in a major way with heat soak. Nothing that a bit of body carving and fans couldn't sort though. :D

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i had this problem until i took car to star performance where the problem was found to be faulty hall sender switch. my car ran great till warmed up then noticibly fell in power as it got to normal temp your best bet is to give to someone with a rolling road to solve the problem as my local dealer had my car three days and could not find a problem ?

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i had this problem until i took car to star performance where the problem was found to be faulty hall sender switch. my car ran great till warmed up then noticibly fell in power as it got to normal temp your best bet is to give to someone with a rolling road to solve the problem as my local dealer had my car three days and could not find a problem ?

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Not sure if that's the same thing, it's not appearing to lack power when warmed up.

However I'll bear that in mind - it seems I can read the inlet air temp through VAG.COM so I'll try that as a reference before I swap back to the standard airbox and try that. If the cheap and obvious fail I've got the other things to look at.

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my warm up procedure is no more than 50% throttle and 3k revs i try to keep it as near 2k as poss when the oil temp hits 50 il give it full throttle but only 4500 rpm till oil hits 70 then its fair game i rarely go (or need to go lol) over 6k revs

That sounds about what VW would recommend Eat This.

I'm about the same but I don't give it full throttle or revs until around 90 but really I drive more economically through the week and only really get my foot down when I go out to play badminton. It's the only open road I see - full throttle and/or revs on my daily drive would have me pushing cars up the road. !lol

For normal driving even when fully warm I rarely exceed 4500 rpm - I wouldn't want to miss that huge lump of torque from 3-4000 rpm with the Schrick! ;)

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dubsingh' date=' try 16v cold plugs, problem is most likely you sparkies are overheating.

[/quote']

so the 16 plugs will screw ok onto the vr head?....i was just reading the post about the hall sender....i havent paid attention but when warm/hot the car dose seem to also what feels like power loss till high revs....where exactlyy is the hall sender !dodge :@ .....how much is it to replace? mines OBD1

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