DemonicPupil

So my Turbo NA project has come to a screeching halt. I can't get it to idle, but I believe that I need to adjust the screw and give it some more air.

When I get it started, after running for about 10 secs, the engine vibrates. It's pretty presistent and in a rythm.

Things I've done:

a) Pulled front cover, followed directions on fc3spro to keep from moving bearings
b) Restabbed CAS
c) Have 460cc primaries (Low Imp) and 550cc secondaries (high imp) (cut the respective resistor pack and spliced correct wires together)
1) I swapped in the 460's to get the car started
2) One of the 550's was leaking pretty heavily
d) Turbo is smoking pretty bad, got a small leak and it's killing my oil pressure (50psi instead of 70 at 2.5k)

So my questions... If one of the 550's is still leaking, will more fuel in one rotor, make the car run extremely rough and cause the vibration? It's like a thud thud thud thud

Even with the timing a few degrees off, that wouldn't cause this horrible vibration would it?

Running an NA fuel pump on TII fuel lines, could the FPR not be putting enough fuel to the injectors?

I'm really lost at this point. Would like to figure out what's causing this vibration/thumping. It's not like driving down the road at 80mph with a bad driveshaft, it's more like someone hitting the car every half second or so.

Thanks for any help.

Icemark

did you change the flywheel???

You have checked compression right???

DemonicPupil

I checked compression on the motor before doing all the work:

130 psi on rear
120 psi on front

I doubt that has changed. I did no work to the drivetrain. Everything was done to the top end of the motor (intakes/exhaust).

I pulled my plugs and it looks like they are fouled up pretty badly. I'll be replacing them this evening.

Would badly fouled plugs cause the pulsation that I was feeling?

As a side note, I revved the motor up to 5.5k and let off. No shaking on the way down, only on the way up. The BOV let off something nasty, so I think I'm going to be overly impressed by how fast this turbo spools up once I get some load on it.

Icemark

wow those are great numbers... but yes fouled plugs could lead to mis-firing and then to erractic operation. Mostly when underload

DemonicPupil

Will my low imp injectors inject if the resistors are not connected? Will they inject less or more?

I got rid of the roughness with some timing work, but my O2 sensor is reading lean (after warm up). No matter what, I can't get it out of lean. At least according to the sensor. It's directly behind the turbo.

Icemark

no they won't work unless you have bypassed the resistor pack somehow.

DemonicPupil

Hmmm, maybe something wrong at the AFM then? I'm going to be reinstalling the BAC to try and get it to idle correctly. I find it extremely odd that I can't get it out of the lean.

Sigh, back to the drawing board. How about the FPR? I put the Turbo fuel rails on. What's the difference in operation between the Turbo FPR and the NA FPR?

DemonicPupil

So I got rid of the shaking. turned out that my fiance didn't tighten all the bolts on the fan. Little wobbly wobbly. Tightened them up, and no more shakes.

However, I still can't get it to idle. I put the BAC back on and extended the wires over to it. The car starts, goes to about 1200-1500ish then slowly goes down and dies.

If I keep my AFC (800 rpm) set to 0, the car dies pretty quick. If I set the AFC (800 rpm) to +30, the car will try to stay alive, but sooner or later dies. I don't seem to have vac leaks anywhere, but I can't seem to figure out why (possibly) my MAF isn't sending the proper signals. I can't find anywhere that would be a vac leak, before or after the throttle. I hooked the BAC up to the Intercooler because I don't have a TID.

I also moved the intake piping off the turbo and went straight to the intercooler to try and get it started. No good either.

So.. my air connections go as such at the moment (bypassing turbo)

AFM -> Intercooler
Intercooler -> Throttle body
BAC -> intercooler
2nd nipple on intercooler -> blocked
After throttle body -> Brake booster, pressure sensor, vac guage (reading 20 psi), twin scroll system

I'm completely stumped, I do believe however that the AFM is not sending the correct info or air is coming from somewhere else and bypassing the AFM. Would this be a good assumption?

Car starts right up now, with no hesitations, just won't hold the idle.

Icemark

you have checked the basics like TPS right???

DemonicPupil

TPS "should" be working. It worked before I took the car apart. It's plugged in. I'll try to find my multimeter and test it. Just can't see why that would give me hell.

Icemark

well TPS and vac leaks are the number one reason for starting/idle issues.

So we should rule that it is set correctly before going anywhere else.

classicauto

iTrader: (3)

How old is that sensor?

I know after a number of years in the exhuast stream of a wankel I'd be a little lean myself.....

DemonicPupil

It's an S4, don't think I need to "set" the TPS??

As for the O2 sensor, again, something that worked before I started this project. I started it up 4 days after taking it apart.

At this point, I'm about to reattach all my non-turbo stuff and see if the car will run at all.

It can ALMOST hold a 500 rpm idle. I think I can hear a vac leak, but I cannot find it if my life depended on it. I tried spraying water around the area, but the wind was blowing and taking the water with it.

I'm thinking maybe the FPR on the TII regulator is shot, or running an NA pump with the TII FPR just isn't building up enough pressure at idle? I'm going to try replacing the TII secondary fuel rail with my NA fuel rail and see if I can get it to hold idle. I'm miffed. At 500 rpm, the AFM flap barely moves, if it moves at all.

Icemark

try spraying Starting fluid (available any auto parts store and even wallmart) around the intake. The RPMs will raise where the starting fluid gets sucked in through a vac leak. Of course you would want to avoid spraying on the turbos or exhaust manifold, but starting fluid evaporates so quick, it will not flare up unless you spray it on a flame.

And yes the S4 TPS is adjustable.

DemonicPupil

Ok so my symptoms are now as follows:

Starts up... idles for about 3-4 secs then dies.

Now I did find out tha the FPD on the primary rail was leaking. I swapped my NA one back in and reran all my fuel lines. Unfortunately, the battery is dead and I can't try to jump it till my fiance gets home.

New question: Could the leak at the FPD have caused the inability to idle? It was a decent leak, steady stream spraying out of the side and filling up the grooves between the housings and the manifold.

I tried adjusting the TPS, but to no avail. This was prior to finding the FPD failure.

Icemark

yes the PD would have a considerbly lower fuel pressure if it is leaking