Resolved Lean? Or coincidence

[CollinClay]

Hello gentlemen (and ladies) I have a mostly stock 90 TSi with the following issue.

First... it is 100% maintained with no boost, oil or fuel leaks. (So far)
Modifications are boost gauge (reading 4psi at rest), muffler delete, mbc, and previous owner put a non identifiable turbo on (looks like an eBay 16g).

I start it up and it runs beautifully, exhaust smells a tad rich on warm up but normal, holds 700rpm flawlessly. Vac shows 0 at idle and -10 on back pressure. Hmmm? Boost shows max of 15psi (plus 4 for the offset, = estimated 19) no fuel cut. Still to high so the stock bsc is going back on tonight. Anyway, after driving for 10-15 min, I loose complete power, checking the engine bay the manifold is red hot. Exhaust has NO smell whatsoever, its like a blowdrier. Car still runs flawlessly but no power.
So, I've read the cat may be clogged. I am hoping to get some input before I get home to complete the following....
Put stock bcs back on, pull the cat out and eliminate that, pull the plugs and inspect.
I have also read that too much timing retard can cause the hot manifold, is it possible that leaving the stock bcs plugged in will cause an Ignition retard? All of this became a noticeable issue after the gauge, mbc and new replacement BPV got installed.
Even if the mbc is allowing too much boost, won't that only be an issue at WOT?
Any thoughts? I find it strange that this is happening after the install. Also I am afraid of driving it over and over possibly risking internal damage. Also valves were silent before this "hot manifold" ordeal, now they are not so quiet....

 

[BabyDSM]

The Guage shouldnt cause any problems, also what kinda mbc is it? Can possibly be faulty and restricting

 

[CollinClay]

I have no idea, its an anodized red block with what appears to be a backwards B and an S or 5 in diamond shape... It seems to be functioning but I'm not sure how to test it.

 

[oneslowwdsm]

Take the intake pipe off and check that turbo for shaft play. My guess is that it is toast.

 

[CollinClay]

Turbo is good....0 shaft play in any direction. I hoping to get the cat off today...we'll see what happens.

 

[Justin Lauscher]

Maybe knock retard because of the extra boost from the mbc causing the red manifold?

 

[CollinClay]

That very well may be, however here are the results from tonight's diagnosis:

The car is back running good but manifold is still getting hot (normal under hard driving) and exhaust smells much better but still a tad lean.

1) I disconnected the boost controller and put it back to stock. Gauge still reads 15psi -the now 6psi at rest. (~9psi total) I think the gauge is garbage

2) I disconnected the gauge from the vac line at the fuel solenoid and tapped it into the TB (for diagnostic purposes)

So I'm betting it was the boost controller all along and I will now put the boost gauge back to the fuel solenoid and see what happens in order to eliminate that as the cause.

If the condition is unchanged then one more thread resolved! ....standby

Pic of controller below...anybody recognize this? Can't find it anywhere.

 

[RyeDawg]

Looks to be a slow boy racing ball and spring style boost controller

 

[CollinClay]

I bet you're right...makes sense. It caused the car to boost weird when it was all the way down...wouldn't spool until like 3500-3700 and then it just slammed and spiked, not smooth at all.

 

[Diamond Star Werks]

Check mechanical and ignition timing, these can cause that if they are off. Make sure mechanical timing is dead on, then check base ignition timing.

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[Diamond Star Werks]

IGNITION TIMING

IGNITION TIMING (2.0L & 2.0L TURBO)

Ensure vehicle is at operating temperature, all accessories are off and transmission is in Park or Neutral. Vehicle front wheels must be in straight-ahead position and curb idle speed set to specification. Turn engine off. Disconnect female connector from ignition timing connector (if equipped).
Using a jumper wire, ground ignition timing adjustment connector (Yellow/Red wire). See Fig 1 . Start engine. Check ignition basic timing. Loosen crank angle sensor hold-down bolt and adjust as necessary. Disconnect ground wire on ignition timing adjustment connector. Check ignition actual timing. Turn engine off. Remove all test equipment.

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Fig 1: Ignition Timing Adjustment Connector Location
G90F00583
Courtesy of CHRYSLER MOTORS.
IGNITION TIMING (Degrees BTDC @ RPM)
Application Basic (1) Actual
1.8L 5 @ 600-800 10 @ 600-800
2.0L & 2.0L Turbo 5 @ 650-850 8 @ 650-850
(1) If vehicle altitude is more than 2300 ft. above sea level, actual timing may be advanced.

 

[Diamond Star Werks]

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[CollinClay]

Dang the images are not coming through... I will indeed check, I know the mechanical timing is on, I am not sure about the Ignition. Thanks for the advice! That will be my next chore.

 

[CollinClay]

Well it made it a whole day this time before the powerloss kicked in. Now I'm leaning toward the wastegate getting stuck open or a vacuum problem causing a malfunction.

It still seems to only be happening when I get that manifold hot or it runs for a while. Car still revs up and runs good just feels like no turbo

Anyone have some insight?

 

[RyeDawg]

You could test your wastegate to see if it's working properly.

 

[Diamond Star Werks]

Wastegate stuck open won't cause you to run lean or get the manifold hot. Do you have a CEL?

 

[CollinClay]

No I don't not, however I do have a MODIS to hook up tonight so hopefully that will shed some insight. I don't have any definitive proof that it's running lean as I do not have an af gauge yet. There may be a few things in play here causing this. What I do know for sure is that first pass with the mbc hooked up began these problems.

I have access to our shop tonight so I'm hoping to get some more info.

Tests to be performed-
Boost leak
Smoke the vac system
MODIS
Fps
Plug check and compression
Wastegate operation
Timing

If anyone has anything to add please advise, I only get my car shop time once in awhile....thanks.

 

[CollinClay]

Update:

Timing was retarted 10degrees off
No boost leaks
No vacuum leaks- secured every one with a clamp
Compression was 150 on every cyl
Plug was definitely white from lean condition
Wastegate was definitely operating
Re calibrated the boost gauge so its dead on

Turbo developed quite a bit of shaft play which is bothersome because it has like 2000 mi on it.
All of a sudden the car is at 20inHg at idle so that's 10 more than before which is great.
So far no power loss but I haven't tested extensively.
Car runs absolutely awesome, only boostin 9psi to stay safe with stock bcs.

Thanks for everyone's input!