Scan Master numbers, Running rich, detonating etc.

[87we410877]

The car runs rough when cold, not horribly but not perfect as it does when warmed up. Seems to be rich. When warmed up it runs so perfect. When into boost above 10 lbs it starts to detonate.

Before i get the scanmaster number out here, Could it be possible that the cam sensor is off a bit or is it either set or not set? Would being off a bit effect timing? I'll have numbers up tonight.

Stock motor and tranny, K&N filter, walbro 255, exhaust, no cat. Everything else is stock.

 

[TurboBuRick]

The engine either runs or it don't when it comes to the cam sensor setting.

Post your scanmaster numbers key on engine off.

 

[87we410877]

Scan Master #'s with:

Key on no start ------- Engine Running Cold

AF - 04 ---------------- 08
L8 - 00 ----------------------- 37
Batt - 11.8 ------------------ 14.1
INT - 128 -------------------- 128
BL - 128 --------------------- 128
MPH - 00 --------------------- 00
CLT - 60 ---------------------- 67
ATS - 65 ---------------------- 63
R - 0 -------------------------- 1200
TPS - 0.40 ------------------- 0.42
IAC - 140 --------------------- 70
CL - 00 ----------------------- 252
MAL - 00 ---------------------- 00
02 Milivolts - 00 -------------- 00

Let me know what you think . IAC does come down to 10-20 when warmed up.

 

[TurboDave]

Cold running engine numbers aren't going to tell us much. Take it for a drive and then pull the numbers warmed up and in closed loop.

 

[Street Lethal]

Stock motor and tranny, K&N filter, walbro 255, exhaust, no cat. Everything else is stock.

Try putting the stock intake back on and check to see if it smooths out. Your stock calibration running with the K&N filter will make a substantial difference without any O2 correction to compensate. If the idle gets better with the stock intake filter, then put the K&N back on and up the fuel pressure until it smooths out...

 

[87we410877]

Try putting the stock intake back on and check to see if it smooths out. Your stock calibration running with the K&N filter will make a substantial difference without any O2 correction to compensate. If the idle gets better with the stock intake filter, then put the K&N back on and up the fuel pressure until it smooths out...

I do not have an adjustable FPR and also, it is a TT chip. Air filter shouldn't make a difference and i specified i had a K&N when i had it made. I am more concerned about the detonation when laying into it than the idle since it smooths out when warmed up.

 

[87we410877]

Cold running engine numbers aren't going to tell us much. Take it for a drive and then pull the numbers warmed up and in closed loop.

Will do. First thing tomorrow AM. Thanks.

 

[Street Lethal]

I do not have an adjustable FPR and also, it is a TT chip. Air filter shouldn't make a difference and i specified i had a K&N when i had it made.

You said everything else was stock, that is why I quoted your words. However think about what you're saying, the rough cold idle and wide open detonation are more than likely being caused by the same issue. It sounds like your lean at idle, and your acceleration enrichment cannot keep up with the extra air. Closed Loop idle won't tell you much, only if you follow the INT to see where your fuel trims initially were...

 

[87we410877]

You said everything else was stock, that is why I quoted your words. However think about what you're saying, the rough cold idle and wide open detonation are more than likely being caused by the same issue. It sounds like your lean at idle, and your acceleration enrichment cannot keep up with the extra air. Closed Loop idle won't tell you much, only if you follow the INT to see where your fuel trims initially were...

Yea that was my mistake i forgot to list the chip. From what my nose it telling me, it is rich at idle. I do have a Fuel pressure gauge on the hood i can monitor that when into the boost. We'll see what the numbers are telling me tomorrow.

 

[Street Lethal]

Yea that was my mistake i forgot to list the chip. From what my nose it telling me, it is rich at idle. I do have a Fuel pressure gauge on the hood i can monitor that when into the boost. We'll see what the numbers are telling me tomorrow.

A datalog and a wideband air/fuel reading throughout would isolate the problem. If you're unsure if you are rich or lean at idle, pull a few plugs out and inspect them. In fact, throw some pics up of the electrodes if you can. If you are detonating during heavy pulls though then you're running lean...

 

[mikestertwo]

TT chips tend to be rich on cold startup. I assume your chip is open loop idle. You may have two different issues here. As mentioned above track your fuel pressure with boost to see where you are at.

 

[TurboBuRick]

Cold running engine numbers aren't going to tell us much. Take it for a drive and then pull the numbers warmed up and in closed loop.

Warm engine numbers won't help with cold start issues.

 

[TurboBuRick]

Scan Master #'s with:

Key on no start ------- Engine Running Cold

AF - 04 ---------------- 08
L8 - 00 ----------------------- 37
Batt - 11.8 ------------------ 14.1
INT - 128 -------------------- 128
BL - 128 --------------------- 128
MPH - 00 --------------------- 00
CLT - 60 ---------------------- 67
ATS - 65 ---------------------- 63
R - 0 -------------------------- 1200
TPS - 0.40 ------------------- 0.42
IAC - 140 --------------------- 70
CL - 00 ----------------------- 252
MAL - 00 ---------------------- 00
02 Milivolts - 00 -------------- 00

Let me know what you think . IAC does come down to 10-20 when warmed up.

O2 millivolts says lean. Do they come up at all as it warms up?

 

[87we410877]

1. 
   AF - 04
   L8 - 29
   Batt - 14.1
   INT - 128
   BL - 142
   MPH - 00
   CLT - 167
   ATS - 95
   R - 750
   TPS - 0.42
   IAC - 02
   CL - 91
   MAL - 00
   02 mv - 812-816
   R degrees after 15 lbs of boost - 2.1
   
   Fuel pressure is 35-38 key on no start. Engine running its 30 and at 15 lbs of boost 50 lbs.
   
   Still detonating but not as bad as usual. Just slightly today.
   
   When cold the car surges slightly like a blower car. It's hunting for something.
   
   Thanks!!

 

[mikestertwo]

Your fuel pressure appears to be a little low. At 15lbs. boost your fuel pressure should be in the 55-60lb range

 

[SCOOBY DOO]

BLM's are 142...you have an air/exhaust leak. Erics chip requires 44 line off running.

 

[Ttype6]

1. 
   BL - 142
   IAC - 02
   

These numbers mean that you have a vacuum leak and/or a hole in the flexible intake pipe between the MAF and the turbo. Somewhere,after the MAF sensor, air is entering the intake stream. The MAF sensor is telling the computer that x amount of air is entering the engine. There is also some other air entering that the MAF doesn't know about. This air is detected by the oxygen sensor when the computer is operating in closed loop. To adjust for this extra air the computer adds more fuel to get the a/f ratio where it needs to be. This is what the BL number means. Default is 128,so any number above 128 means the computer is adding fuel. The higher the number,the more the computer is adding to the default amount. 14 numbers higher than default of 128 is a lot. The computer is adding a lot of fuel on top of the amount it is programmed to do.

Now we have more air and fuel entering the engine so the idle rises up. the computer then attempts to lower the idle back to where it should be by restricting the amount of air that gets into the engine by closing the Idle Air Control valve. The IAC number of 02 means that the IAC valve is 2 clicks away from closing as much as it can.

The IAC and BL numbers are telling us that air is entering the engine somewhere after the MAF sensor.

You must set the fuel pressure to 43 psi. with the vacuum line disconnected from the regulator.
This is easily accomplished with big adjustable pliers,but it must be done with the egine idling at operating temperature.
It is very sensitive to the pliers and is why this must be done while the engine is running.
If you tried clamping it in a vice,you would over crush it and there is no going back.

If you still have detonation after fixing the leak/leaks and raising the fuel base pressure,I would look at the stock fuel injectors as the next possible cause.

 

[87we410877]

These numbers mean that you have a vacuum leak and/or a hole in the flexible intake pipe between the MAF and the turbo. Somewhere,after the MAF sensor, air is entering the intake stream. The MAF sensor is telling the computer that x amount of air is entering the engine. There is also some other air entering that the MAF doesn't know about. This air is detected by the oxygen sensor when the computer is operating in closed loop. To adjust for this extra air the computer adds more fuel to get the a/f ratio where it needs to be. This is what the BL number means. Default is 128,so any number above 128 means the computer is adding fuel. The higher the number,the more the computer is adding to the default amount. 14 numbers higher than default of 128 is a lot. The computer is adding a lot of fuel on top of the amount it is programmed to do.

Now we have more air and fuel entering the engine so the idle rises up. the computer then attempts to lower the idle back to where it should be by restricting the amount of air that gets into the engine by closing the Idle Air Control valve. The IAC number of 02 means that the IAC valve is 2 clicks away from closing as much as it can.

The IAC and BL numbers are telling us that air is entering the engine somewhere after the MAF sensor.

You must set the fuel pressure to 43 psi. with the vacuum line disconnected from the regulator.
This is easily accomplished with big adjustable pliers,but it must be done with the egine idling at operating temperature.
It is very sensitive to the pliers and is why this must be done while the engine is running.
If you tried clamping it in a vice,you would over crush it and there is no going back.

If you still have detonation after fixing the leak/leaks and raising the fuel base pressure,I would look at the stock fuel injectors as the next possible cause.

Sounds like an excellent start and it all makes sense. So what exactly am I doing with these plyers? I assume I will be crushing the regulator or return line in some way?

 

[Chuck Leeper]

IAC - 02

As mentioned........Vac leak.

 

[Ttype6]

Sounds like an excellent start and it all makes sense. So what exactly am I doing with these plyers? I assume I will be crushing the regulator or return line in some way?

You'll be using them to bring the bottom and top of the regulator body closer to each other. This will shorten a spring inside the body. Very sensitive. You'll see how sensitive it is when you watch the gauge while using the pliers. The spring is actually in the lower half of the 2 halves of the body.