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What the heck, no boost?

4K views 24 replies 6 participants last post by  Caleditor 
#1 ·
Just took a drive and the car all day has been doggy. So stuck on the datalogger and when I got home and looked, no boost. WTH?

I haven't been out to pop the hood, (sheesh! below 0C/32F!). is there any common "failures"? Boost bypass valve? It is quiet and generally smooth, mpg is down (20ish) and of course, the roast the tires on command is gone off the line.

Will it idle or run ok with the belt tossed (? seems like it would be sorta plugged up that way). I haven't heard it do anything odd. Only thing done was CASE learn on a Tech2, it did take the edge off how well it ran before, but most of my KR issue is gone now.
 
#2 ·
Try running it for another couple of weeks like that and see if it fixes itself. Sometimes these superchargers do that. Whatever you do, DO NOT OPEN THE HOOD!!!

:wtf:

Yes, it does run without a blower belt, if that is there see if you bypass valve opens when the engine is started and if it closes when you open the throttle fast. If still not boost, take the belt off and rotate the pulley, if it doesn't feel heavy like 10lbs of rotating mass, it's time for a GENV blower, most likely the coupler in the blower is gone and the metal pins that go in it all broke each other.

And yeah, get outside right now, you lazy bum and check it !!! :lmao:
 
#3 ·
One of the stock pulleys might have disentegrated, tossing the belt. That has actually happened to me twice.
 
#4 ·
Every once in a while (rare, like 1x a month or less) hear a "chirp" like a belt slipping. That and my mysterious KR (look to the end of the thread) the warning signs?

I'll get out there in a few, it is daylight (it was 1am when I got home, and I had "better" things to do last night... ;)

If you can't open the files, simply I was all of a sudden starting to see KR at CRUISE on Friday, 11% throttle, 4th gear lockup, it would cycle, start going to 1-2 degrees, then decay down, then up to 4 degrees, then decay down then up to 7 degrees and decay down, etc , up to 15 degrees! No noises, not running badly, nothing, totally weird. Makes me wonder if the blower was stripping out at that time.
 
#5 ·
Ok, no "major" problems, tossed belt, froze up idler pulley.

I think I have a spare I can pull off my Cadillac LT1 for now...



 
#6 ·
Hey you should have opened the hood and look when you heard that Chinging noise. :icon_twis

BTW Highline say that the M90 pumps just fine on the GT500 Clown car.
Oh clone car
 
#7 ·
I almost did, figured it was nothing but the moisture out... Ha, go figure!

To think some people put M112's on a 3800!

I guess the GT500C is just a 4.6L anyway....

How small pulley does that thing use?
 
#15 ·
Why only in PE?
I was ok with it be a mechincal issue, but someone kept saying it was only in PE mode. What does PE have to do with a bad bearing?
 
#16 ·
Most often PE did hit at 125 kPA give or take a little....(cosmic coincidence?)

We'll datalog tonight.....
 
#17 ·
Kieth got back to me today. Jay will be in on wednesday. Highline will have to wait until the weekend to drive the white turd. I am sure it will break again. Maybe this time the car will have over 5000 mile on it. LOL
Motor out 3 times in 5000.

I think they pulled the enige to install the blower. The cradle/crossmember had been out before he bought it. It only had 3800 on it then.
DON"T BUY A F.O.R.D.>:icon_lol:
 
#18 ·
Check too with Intense guys, they are resellers too...
 
#19 · (Edited)
Well, I am getting fed up... STILL a freaking ton of KR.

COLD TEMPS! Lets see, cold soak, just get it into operating temps (70C) where KR works, and I can give it a quick stab say 50-60% throttle and it will soar to 5-15 degrees.

WTH?

Ready to pull off KR so I can listen audible.... Sheesh, that is the "old" way anyway, go do the ear method and let it rattle till I hear it!

It pulls so much timing out it feels like I am stepping into a bucket of crap....
 
#21 · (Edited)
I am comming into this a little late so some of this stuff may have already been said/tried.. but anyway,

You said this showed up only after a pulley swap?
What was the previous pulley?

Is the PCM aftermarket? are the TM settings raised? I had a lot of part throttle KR due to the PCM pulling timming for Torque Managment. (bumped the TM limits to lke 500 and the KR disapreared)

Are you scanning O2 values? What are they at durring the same KR times?

When its cold is this not happening at all? That would lead me to think it might be real, or atleast not TM.

edit...

one last thing to check for if it is a TM issue,
From a stop, if you slowly got WOT (say, just enough to avoid wheel spin) is there any KR?
If not, then I would again guess its your PCM's trq mngmnt, not true KR.
 
#22 ·
Stock engine. Stock tune, ONLY "mod" is gutted air box. No way in God's green earth is a gutted airbox going to do this.

I have tried about every concieveable tuning to it, nothing. So today I got ticked and pulled KR below 4000 rpm. Voila, problem gone. with 15 degrees KR showing up all the time, you would think I would HEAR it rattle like freaking crazy with out the PCM yanking timing, so guess what? Not a PEEP. SOMETHING must be whacked under there near the KS. I did try brake torquing it and it does make an almost squeak when the engine starts to come back when I get off the gas some. I am wondering if that is it. Now to spend time looking. Top side I haven't been able to find anything.

Exhaust make noise sometimes at the flex coupling/ball coupling? That might jive for the sound. Almost a scratch is a better way to describe it. It would make sense if the movement of the engine would be the culprit. Mounts don't SEEM bad to me, but I am going to do what one of the members here did and put a torque strap in and see if that doesn't "fix" it. I hate how most FWD's move around anyway. I don't like the feeling in the car.

I will try slowly from a stop, I don't think I have tried it, but the typical scenario is when I hit PE mode, it skyrocket KR, from 3-4 degrees up to as high as 15. A 50 mph cruise and go to 50% throttle is enough to send it to 15 degrees everytime.

O2's are in the 900mV range (remember, don't tune with NB's!)

Lowering timing tends to help, but you have to get it soooo low power is sucking and honestly that is probably sending EGT's soaring causing all sorts of other issues....

For now, KR is disabled under 4000 rpm. I get very very little now any other time. I have run in the past the high and low tables set as high and still never had an issue. In warmer weather too.

Gotta me mechanical. But to find it isn't easy... Anyone with ideas or common issues seen?







Some, very little. Not enough to worry about. But with power so low, if it is engine movement without it probably won't move anyway! Oh and 3800's don't break mounts right? :)

Did it have KR with the belt off?
 
#25 ·
Knock Sensor (KS) System Description
Purpose
Varying octane levels in today's gasoline may cause detonation in some engines. Detonation is caused by an uncontrolled explosion (burn) in the combustion chamber. This uncontrolled explosion could produce a flame front opposite that of the normal flame front produced by the spark plug. The rattling sound normally associated with detonation is the result of two or more opposing pressures (flame fronts) colliding within the combustion chamber. Though light detonation is sometimes considered normal, heavy detonation could result in engine damage. To control spark knock, a knock sensor (KS) system is used. This system is designed to retard spark timing when spark knock is detected in the engine. The KS system allows the engine to use maximum spark advance for optimal driveability and fuel economy.

Operation
The PCM contains integrated knock sensor (KS) diagnostic circuitry. Input signals from the knock sensors are used to detect engine detonation, allowing the PCM to retard ignition control (IC) spark timing based on the amplitude and frequency of the KS signal being received.

The knock sensors detect abnormal vibration (spark knocking) in the engine. The knock sensors are mounted in the engine block near the cylinders. The knock sensors produce an AC signal voltage under all engine operating conditions. During engine operation, the PCM calculates the average voltage of each knock sensor's signal. If the knock sensor system is operating normally, the PCM should monitor KS signal voltage varying over 0.5 volt above and below the calculated average voltage.

Diagnosis
If the PCM malfunctions in a manner which will not allow proper diagnosis of the KS circuits, DTC P0325 will set.
DTCs P0327 and P0332 are designed to diagnose the knock sensors, and related wiring, so problems encountered with the KS system should set a DTC. However, if no DTC was set but the KS system is suspect because detonation was the customer's complaint, refer to Detonation/Spark Knock .

Detonation/Spark Knock

Fuel System
• Check for low fuel pressure. Refer to Fuel System Pressure Test (VIN K) or Fuel System Pressure Test (VIN 1) .

• Check for contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .

• Check items that can cause an engine to run lean (Long Term FT significantly in the positive range). Refer to Diagnostic Aids for DTC P0171 Fuel Trim System Lean .

Ignition System
  • Check the spark plugs for proper heat range and reach.

Engine Cooling System
Check for obvious overheating problems:

• Low engine coolant.

• Restricted air flow to radiator, or restricted water flow through radiator.

• Inoperative electric cooling fan circuits. Refer to Electric Cooling Fan Diagnosis .

• Correct coolant solution should be a 50/50 mix of GM 1052753 or equivalent antifreeze coolant and water. Refer to Cooling System Draining and Filling in Engine Cooling.

Engine Mechanical

• Excessive oil in combustion chamber-Leaking valve seals. Refer to Valve Stem Oil Seal and Valve Spring Replacement in Engine Mechanical.

• Low cylinder compression. Refer to Engine Compression Test in Engine Mechanical.

• Combustion chambers for excessive carbon buildup. Clean using top engine cleaner. Follow instructions on can.

• For incorrect basic engine parts. Inspect the following:

- Camshaft

- Cylinder heads

- Pistons, etc.

• Refer to Engine Compression Test in Engine Mechanical.

Additional Checks

• Check for proper EGR system operation. Refer to DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient .

• Check the transaxle range switch input with the vehicle in drive and the gear selector in drive or overdrive.

• Check TCC operation. TCC applying too soon can cause the engine to spark knock. Refer to Diagnostic Starting Point - Automatic Transmission in Automatic Transaxle.

• If scan tool readings are normal and there are no engine mechanical faults, fill the fuel tank with a known quality gasoline that has a minimum octane reading of 87 (for VIN K, 91 for VIN 1) and re-evaluate vehicle performance.

DTC P0325 Knock Sensor (KS) Circuit
Circuit Description
The PCM contains integrated knock sensor (KS) diagnostic circuitry. Input signals from the knock sensors are used to detect engine detonation, allowing the PCM to retard ignition control (IC) spark timing based on the amplitude and frequency of the KS signal being received. The knock sensors produce an AC signal under all engine operating conditions. During engine operation, the PCM calculates the average voltage of each knock sensors signal. If the knock sensor system is operating normally, the PCM should monitor KS signal voltages varying over 0.5 volt above and below the calculated average voltage. If the PCM malfunctions in a manner which will not allow proper diagnosis of the KS circuits, DTC P0325 will set.

Conditions for Running the DTC
• No TP sensor, VSS, CKP, MAF, or ECT DTCs are set

• VIN K - Engine speed is between 1000-4000 rpm.

• VIN 1 - Engine speed is between 1000-3000 rpm.

• VIN K - Throttle angle is more than 3 percent.

• VIN 1 - Throttle angle is more than 15 percent.

• VIN K - Engine load is more than 20 percent.

• VIN 1 - Engine load is more than 45 percent.

• Engine coolant temperature is more than 75°C (167°F).

• Maximum spark retard is less than 15°.

• System voltage is more than 9 volts.

Conditions for Setting the DTC
• The PCM detects a malfunction in the integrated knock sensor diagnostic circuitry which will not allow proper diagnosis of the knock sensor circuits.

• Above conditions for at least 1 second.

Action Taken When the DTC Sets
The PCM stores conditions which were present when the DTC set as Failure Records only. This information will not be stored as Freeze Frame Records.

DTC P0327 Knock Sensor (KS) Circuit
Circuit Description
The PCM contains integrated knock sensor (KS) diagnostic circuitry. Input signals from the knock sensors are used to detect engine detonation, allowing the PCM to retard ignition control (IC) spark timing based on the amplitude and frequency of the KS signal being received. The knock sensors produce an AC signal under all engine operating conditions. During engine operation, the PCM calculates the average voltage of each knock sensors signal. If the knock sensor system is operating normally, the PCM should monitor KS signal voltages varying over 0.5 volt above and below the calculated average voltage. If the PCM detects a knock sensor 1 signal voltage within the calculated average voltage range, DTC P0327 will set.

Conditions for Running the DTC
• No TP sensor, VSS, CKP, MAF, or ECT DTCs are set

• VIN K - Engine speed is between 1000-4000 rpm.

• VIN 1 - Engine speed is between 1000-3000 rpm.

• VIN K - Throttle angle is more than 3 percent.

• VIN 1 - Throttle angle is more than 15 percent.

• VIN K - Engine load is more than 20 percent.

• VIN 1 - Engine load is more than 45 percent.

• Engine coolant temperature is more than 75°C (167°F).

• Maximum spark retard is less than 15 degrees.

• System voltage is more than 9 volts.

Conditions for Setting the DTC
The PCM detects a knock sensor 1 signal voltage within the calculated average voltage range.

Action Taken When the DTC Sets
The PCM stores conditions which were present when the DTC set as Failure Records only. This information will not be stored as Freeze Frame Records.

Diagnostic Aids
Check for the following conditions:

• Poor connection at the PCM or knock sensor 1.

Inspect knock sensor 1 and PCM connectors for backed out terminals, broken locks, and improperly formed or damaged terminals.

• Misrouted harness.

Inspect the knock sensor harness to ensure that it is not routed too close to high voltage wires such as spark plug leads.

Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

DTC P0332 Knock Sensor (KS) 2 Circuit
Circuit Description
The PCM contains integrated knock sensor (KS) diagnostic circuitry. Input signals from the knock sensors are used to detect engine detonation, allowing the PCM to retard ignition control (IC) spark timing based on the amplitude and frequency of the KS signal being received. The knock sensors produce an AC signal under all engine operating conditions. During engine operation, the PCM calculates the average voltage of each knock sensor's signal. If the knock sensor system is operating normally, the PCM should monitor KS signal voltages varying over 0.5 volt above and below the calculated average voltage. If the PCM detects a knock sensor 2 signal voltage within the calculated average voltage range, DTC P0332 will set.
 
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