Tuning Woes

[dourtyb]

Got the Typhoon out of mothballs since the weather is getting nice. Apparently it didn't fix itself over the winter. Darn the luck. I'm still struggling with TunerPro. I'm running version 4.14 with the following xdf and ads files:

1227749_2&3Bar_58_rev6a.ads
58_2&3Bar_Beta_0.9.1.xdf

The readings on Pressure: 3bar from 1 bar read 2.2 at idle. After digging in the ads file I see that the formula for this variable is (Raw*1.23) + 2.2. Thus it seems that Tuner Pro is seeing a value of 0 from the ALDL stream for Raw Pressure.

The vacuum reading at idle seems to be pretty close. My analog gauge shows about 20 inHG while Tuner Pro shows about 18.75 inHG.

I'm assuming the pressure and vacuum both come from the MAP sensor. How can one be right and the other be wrong? Is this a display issue, ALDL issue, is Map sensor issue?

The wiring and vac lines all look good. Anyone know a way to test the Map sensor?

Thanks,

 

[turbodig]

Re: Tuning Woes

Got the Typhoon out of mothballs since the weather is getting nice. Apparently it didn't fix itself over the winter. Darn the luck. I'm still struggling with TunerPro. I'm running version 4.14 with the following xdf and ads files:

1227749_2&3Bar_58_rev6a.ads
58_2&3Bar_Beta_0.9.1.xdf

The readings on Pressure: 3bar from 1 bar read 2.2 at idle. After digging in the ads file I see that the formula for this variable is (Raw*1.23) + 2.2. Thus it seems that Tuner Pro is seeing a value of 0 from the ALDL stream for Raw Pressure.

The vacuum reading at idle seems to be pretty close. My analog gauge shows about 20 inHG while Tuner Pro shows about 18.75 inHG.

I'm assuming the pressure and vacuum both come from the MAP sensor. How can one be right and the other be wrong? Is this a display issue, ALDL issue, is Map sensor issue?

The wiring and vac lines all look good. Anyone know a way to test the Map sensor?

Thanks,

Whatcha running for a chip... does it have the ALDL patch in it?

 

[dourtyb]

Re: Tuning Woes

I think it has the ALDL patch. Jim Sloan did the original tuning on it. Is there a way I can tell by looking at the bin?

 

[turbodig]

Re: Tuning Woes

I think it has the ALDL patch. Jim Sloan did the original tuning on it. Is there a way I can tell by looking at the bin?

You'd know by what you have to do to make tunerpro connect. If you have to jump through a bunch of hoops to get it to connect, you don't have it.

 

[SBNova]

Re: Tuning Woes

I never had a problem getting TP to connect on my stock $58 bin. The only reason I had to get a patched bin was to emulate. I could NEVER read data and emulate simultaneously without it.

 

[dourtyb]

Re: Tuning Woes

I'm not having any problems getting TunerPro to link up with the Ostrich or ALDL. Just the MAP reading issue.

 

[SBNova]

Re: Tuning Woes

Under 3 bar psi, I have this;
BSTPRESS 3 BAR TURBO BOOST PRESSURE PSI =.145*(1.23*N + 2.2)
Is it PSI or MAP 3 bar filtered that you are trying to correct?

 

[dourtyb]

Re: Tuning Woes

Its not the boost reading I'm looking at. At idle that would be zero. Its the MAP Pressure (Calculated 3-bar from 1 bar).

 

[dourtyb]

Re: Tuning Woes

Did some further testing tonight and I'm 99% sure its the map sensor. I checked the voltage at the map sensor using jumpers. I've got +5 on the reference and .4 on the signal wire at idle. I picked up a 2bar at the local parts store since that is all they stock. I get +5 on the reference and 1.4 on the signal wire. According to my Chevy Fuel Injection manual a normal voltage reading at idle should be between 1.2 and 1.9. I guess I'll track down a 3 bar tomorrow.

 

[dourtyb]

Re: Tuning Woes

New map...same problem. A little more troubleshooting and I've narrowed it down to a grounding problem. If Anyone know where the ground wire from the map goes? Does it tie into one of the grounds on the back of the heads? I'm digging through the service manual now and will head out to the garage after dinner to trace it down.

 

[dourtyb]

Re: Tuning Woes

Talked to Jim Sloan tonight and did some more troubleshooting. What I know:

1. Map and Coolant sensor share same ground to ECM (B6 C307).
Unsure of which coolant sensor. I think we have 2. One on intake manifold and one in a head.

2. I get 5 volt reference to map from ECM.

3. Voltage coming out of MAP matches voltage going into ECM. (F15 C311)

4. Engine temp appears to be normal in TunerPro. Cut ground and temp goes to minimum value.

5. Ground MAP to engine and I get a reading of 28kpa at idle.

6. Use existing ground and I get a reading of 2.2kpa

7. run new ground from ECM to MAP and I get a code 15 CTS low because the coolant sensor isn't grounded. MAP still reads 2.2kpa.

8. This truck is driving me crazy.

 

[leroy]

Re: Tuning Woes

Have you ruled out the connectors ....ecm and MAP? I can mail you another ecm connector, if you need it.

Jim

 

[leroy]

Re: Tuning Woes

Have you ruled out the connectors ....ecm and MAP? I can mail you another ecm connector, if you need it.

Jim

The MAP connector is more suspect, since the coolant readings appeared normal.

Jim

 

[turbodig]

Re: Tuning Woes

Talked to Jim Sloan tonight and did some more troubleshooting. What I know:

1. Map and Coolant sensor share same ground to ECM (B6 C307).
Unsure of which coolant sensor. I think we have 2. One on intake manifold and one in a head.

2. I get 5 volt reference to map from ECM.

3. Voltage coming out of MAP matches voltage going into ECM. (F15 C311)

4. Engine temp appears to be normal in TunerPro. Cut ground and temp goes to minimum value.

5. Ground MAP to engine and I get a reading of 28kpa at idle.

6. Use existing ground and I get a reading of 2.2kpa

7. run new ground from ECM to MAP and I get a code 15 CTS low because the coolant sensor isn't grounded. MAP still reads 2.2kpa.

8. This truck is driving me crazy.

Have you tried a copy of DM by any chance.... just to rule out a scan-tool config issue?
The 20-run hobbled download version should work fine as a test...


Later,

Dig

 

[dourtyb]

Re: Tuning Woes

Yeah...I see the same 2.2kpa at idle using DM. I've verified this by looking at the voltage going into the ECM. I've cut the ground on the MAP side and used a jumper to rule out the connector. Same story, low voltage back to ECM when using that ground. I'll take another stab at it tonight. Oh yeah..watch out for the hood latch, it will leave a knot on your head. ;-)

 

[turbodig]

Re: Tuning Woes

Yeah...I see the same 2.2kpa at idle using DM. I've verified this by looking at the voltage going into the ECM. I've cut the ground on the MAP side and used a jumper to rule out the connector. Same story, low voltage back to ECM when using that ground. I'll take another stab at it tonight. Oh yeah..watch out for the hood latch, it will leave a knot on your head. ;-)

Check the cyl head ground and the intake manifold behind the alternator.

Something that might help you isolate...

Get one of the little tube tools that allow you to take the terminals out of the MAP connector.
Take the ground out, and run your own back to the ECM.

Got a wide-band installed by any chance? I've seen them cause ground issues due to current draw...

Later,