1998 A4 1.8TQM GT3071R build starting

[black99.5a4]

No, I didn't think I would need to since the rods are all balanced to +/- 1 g and the flywheel and clutch are all balanced before hand.

actually.. if you would of taken it to get it balanced.. even your stock parts, would of seen some material missing to get it closer for when you plan to high rev it.. OEM TDI crank in my B6 build, had material removed. CM pressure plate that says pre balanced, needed some weight added to it in 2 spots. ECS flywheel that is suppose to be balanced, needed some material removed.

Shoulda spent the 150 bucks.

as long as you put the pistons back in the cylinders that they came out of, you'll be fine.

This is true for a stock build, but when high revving, unbalanced rotating assembly is the killer or cause of the killer, most of the times. Like I said above, OEM is balanced within a percentage. If you take it to a good machine shop, they will get a lot closer, a lot tigher of a percentage.

[black99.5a4]

Your idle issue is due to the BOV, I have the exact same thing happen to me when i pop it into neutral while driving around. To get around it I keep it in gear till about idle when coming up to stops and it hasn't died on me yet.

I never had this issue when running my Forge 004. I'd say both of you have a small vacuum leak somewhere.

[dowsett6]

Due to not recirculating the air. The engine thinks X amount of air is going in so it dumps X amount of fuel. but you get rid of Y amount of air through your BOV, so then the 02 sensor notices that and tries to correct it by cutting Y amount of fuel, but which time your BOV is closed and your back at X amount of air. So now the 02 sensor tries dumping more fuel, over and over again... which makes your idle go up and down.

[black99.5a4]

I think what you're thinking of when you're shifting, you run rich b/c its dumping fuel.. the BOV shouldnt be affecting your idle at all. My car idled perfectly and ran fine (other then slightly and i mean EVER so slightly between shifts) for 2+ years with a BOV.. no bad idle, no idle search, etc.

[dowsett6]

I think what you're thinking of when you're shifting, you run rich b/c its dumping fuel.. the BOV shouldnt be affecting your idle at all. My car idled perfectly and ran fine (other then slightly and i mean EVER so slightly between shifts) for 2+ years with a BOV.. no bad idle, no idle search, etc.

ohhh, ya that makes more sense. Maybe it is because of our ford mafs then?

[black99.5a4]

It might be. Hit up Tapp for a revision. He uses 4.2 Audi V8 MAF's now. Might help.

[John Gutmannnn]

I think what you're thinking of when you're shifting, you run rich b/c its dumping fuel.. the BOV shouldnt be affecting your idle at all. My car idled perfectly and ran fine (other then slightly and i mean EVER so slightly between shifts) for 2+ years with a BOV.. no bad idle, no idle search, etc.

My issue isn't how the car idles, its how the car goes back to idle, which is what I think dowsett6 is saying too. When I rev mine, it has a hard time finding the correct idle point. If you don't recirculate the air wouldn't this cause this issue.

Also, contrary to what I have been told should be happening, I am building boost without the engine being under load (aka not driving the car).

Also what are the chances of an intercooler leaking air?

[black99.5a4]

My issue isn't how the car idles, its how the car goes back to idle, which is what I think dowsett6 is saying too. When I rev mine, it has a hard time finding the correct idle point. If you don't recirculate the air wouldn't this cause this issue.

Also, contrary to what I have been told should be happening, I am building boost without the engine being under load (aka not driving the car).

Also what are the chances of an intercooler leaking air?

What air are you recirculating at idle and revving up? none.. you only recirculate or blow off, when you are building enough boost to make the spring move, piston open, etc.

[John Gutmannnn]

What air are you recirculating at idle and revving up? none.. you only recirculate or blow off, when you are building enough boost to make the spring move, piston open, etc.

I don't understand your point....When I rev my car, the DV moves to "blow-off" air...I am not recirculating this air. I am asking if this could be causing the issue...

[black99.5a4]

you arent getting my point.

you are saying b/c your car isnt recirculating air that its causing your issue.. i've said countless times above that i ran a BOV for 2 years on my car without a single idling issue.. my ONLY issue was between shifts, it would get slightly rich real quick, something you couldnt even notice driving the car...

you are asking that when you rev the car up and let it fall, it cant find idle at first.. there is no REAL boost at idle, to circulate back into the system to "help you find your idle".. its not your BOV that is causing your issue, unless its leaking where ever its clamped on.

this could be a MAF issue, MAF placement issue.. tunes are very sensitive to where the MAF is placed.. in relation to how close or far away any bends are in the TIP. You are trying to follow a road that isnt your issue, imo.

[nunya]

Whats your throttle angle looking like? Max should be =<90 degrees.

Linky

--dillon

[John Gutmannnn]

you arent getting my point.

you are saying b/c your car isnt recirculating air that its causing your issue.. i've said countless times above that i ran a BOV for 2 years on my car without a single idling issue.. my ONLY issue was between shifts, it would get slightly rich real quick, something you couldnt even notice driving the car...

I AM NOT saying this is causing my issue...hence what I said earlier.

I am asking if this could be causing the issue...

you are asking that when you rev the car up and let it fall, it cant find idle at first.. there is no REAL boost at idle, to circulate back into the system to "help you find your idle".. its not your BOV that is causing your issue, unless its leaking where ever its clamped on.

The tune for the car is, from what I have been told, tuned for having the air recirculate from the DV back into the intake. This means the car is expecting more air. So if I rev my car and air blows off to atmosphere, I don't see how this wouldn't cause an issue if the car is getting less air then it is expecting.

this could be a MAF issue, MAF placement issue.. tunes are very sensitive to where the MAF is placed.. in relation to how close or far away any bends are in the TIP. You are trying to follow a road that isnt your issue, imo.

So what are the symptoms of this that point to the MAF? I thought if it was a MAF issue, it wouldn't even idle correctly. The issue is not with the car idling, the issue is with the car finding the idle point. So when I rev the car, the rpms drop to below idle and then the car compensates and gets back to idle after a few iterations of over compensating.

[lowandslow4now]

I don't know if this helps but when I first setup my BT I had a Baileys DV vented to atmosphere and it ran like crap. The idle when cold would be about 1k and bounce alittle, once it got warm most of the symptoms went away. But were still similar. Also I had an issue with the way my maf was setup. At first it was setup with a 90, then MAF and filter. It would cause me to stall if at a cruise and then put into neutral. I solved it by putting a 90,then about 12" pipe, 90 and then MAF and Filter. After I changed both things the car ran perfect for me with no issues. Good luck and I hope you get it settled.

[John Gutmannnn]

Did you connect the DV to recirculate to the intake?

[lowandslow4now]

I never did I ended up just picking up the forge 004 BOV.

[John Gutmannnn]

I know the issue used to exist with the ford lightning MAF but I haven't read anything about the new Audi V8 MAFs, which is what I am using. Is there anyway to tell if it is the intake issue/MAF issue by taking logs?

Why would it run better with that then a DV? I thought the operated basically the same.

[lowandslow4now]

From when I tested it before I swapped to the BOV the DV stays partially open. You can test by put your hand over the DV creating a seal and rev it alittle and see if it gets better. I am not familiar with the tapp file and what the MAF should be pulling at idle.

[John Gutmannnn]

Now for sale:

http://www.audizine.com/classifieds/...?product=44994

I no longer have anywhere to work on the car so the project is doomed if I keep it. Also, with the commitment I need to make to school, I don't have the time for a car that requires this much attention anymore.

Priced at $7000 firm. Before anybody hates on the price, there is EASILY over $5000 worth of parts on the car.

[A4Rob]

Now for sale:

http://www.audizine.com/classifieds/...?product=44994

I no longer have anywhere to work on the car so the project is doomed if I keep it. Also, with the commitment I need to make to school, I don't have the time for a car that requires this much attention anymore.

Priced at $7000 firm. Before anybody hates on the price, there is EASILY over $5000 worth of parts on the car.

Sad to see, but good luck with the sale. Someone will get a very good deal.

[John Gutmannnn]

So since I am sitting here bored, I figured I would ask a few more questions about the idle issue. I saw a thread in general B5 discussion this past week and it seems like someone may have been having almost the same issue as me. Since I ended up going through almost everything people were pointing out, could this in fact be an issue with MAF placement? I have recirculated the DV, cleaned the TB, did a TBA, connected a boost gauge to see it is pulling correct vacuum.

I originally refused to believe this is a MAF issue because the MAF is brand new and the intake setup was bought from someone who said the intake worked on a Tapp tune, BUT he had the Ford Lightning MAF. But I am starting to think now it could be how the air is flowing through the MAF.

Is there someway I can test if the MAF is the issue? (in the spring) Can I connect some ridiculous like 3 foot straight intake coming from a 90 off the turbo just sticking out of the engine bay to see if it would idle correctly? I feel like if I put the MAF at the end it would have smother airflow, and would be a clearer indication of it is a MAF placement/intake issue.

[onemoremile]

Just unplug the MAF and see if the idle situation changes. That will let you know if it is the culprit.

What are your vac readings when at a steady idle?

[John Gutmannnn]

Just unplug the MAF and see if the idle situation changes. That will let you know if it is the culprit.

What are your vac readings when at a steady idle?

When I didn't have the MAF plugged in it ran like shit. But I don't see how that would point to an intake CONFIGURATION issue, unless I am missing something. I thought with the intake configuration if you have it routed wrong around the MAF it will cause turbulence and give skewed readings.

At idle I believe the vacuum was 20 in-hg on the boost gauge, which I was told is correct.

[John Gutmannnn]

I was told by someone tonight they had the same problem when they didn't have their vacuum canister connected. I don't think I even have the metal rod and rubber bulb connected, but I know for sure I broke the T that is between the bulb and the canister. I didn't think any of this was tied to throttle, I guess next time I screw with the car I should try to fix this and see if it works.

[nunya]

I was told by someone tonight they had the same problem when they didn't have their vacuum canister connected. I don't think I even have the metal rod and rubber bulb connected, but I know for sure I broke the T that is between the bulb and the canister. I didn't think any of this was tied to throttle, I guess next time I screw with the car I should try to fix this and see if it works.

Mine is removed completely. No issues.

[John Gutmannnn]

Mine is removed completely. No issues.

Your vacuum canister or the rod and bulb on the TB?

Also, I found a cheap shop, so the project is back on. Car should be out here in august, I will be working on it all winter. Probably gonna pull the engine again and do some more stuff in the engine bay. But first I really want to figure out this issue for getting it to run correctly.

[nunya]

Your vacuum canister or the rod and bulb on the TB?

Also, I found a cheap shop, so the project is back on. Car should be out here in august, I will be working on it all winter. Probably gonna pull the engine again and do some more stuff in the engine bay. But first I really want to figure out this issue for getting it to run correctly.

Anything cruise control related. When i put the IM spacer on it made it all rather useless. I never use CC anyways on either of my cars.

--dillon

[John Gutmannnn]

Anything cruise control related. When i put the IM spacer on it made it all rather useless. I never use CC anyways on either of my cars.

Hmm....That sucks that this doesn't seem to be the issue then. I didn't think omitting CC parts would cause any issues anyways.

Still at a loss for why this is happening then. Guess I will have to look at it when I get situated in the new place. I cannot wait to resume working on this since it has been like 9 months since I have even touched the car.

[John Gutmannnn]

This sucks, but I am 100% serious this time:

http://forums.vwvortex.com/showthrea...8#post73543448

I need a new DD that is reliable.